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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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r r Cover: Reptiles and Amphibians of Yosemite National Park, Special Number YOSEMITE NATURE NOTES January, 1946 Price 25 Centsr
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About the Author

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r r Myrl V. Walker, 1931r
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r Myrl V. Walker, 1931r
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r Myrl V. Walker was born March 20, 1903.r He married Wilda O. Walker in the 1920s.r He also began collecting fossils in the 1920sr as a student of Dr. George F. Sternberg,r an early Kansas fossil collector,r and later studied under Dr. L. D. Wooster, a paleonthologist.r Walker began teaching Junior High at Protection, Kansas, while attending Fort Hays State College during summer and later full time.r He received his bachelor’s degree in 1927.r After graduating, Walker taught high school at Plainville, then at the biology department at Kansas State Teachers College in 1929 (now Fort Hays State University).r In 1930 he was high school principal, coach, and science instructor.r He received his master’s degree in vertebrate paleonthology from the University of Kansas in 1931.r

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r Walker became a seasonal ranger naturalist in 1933.r In 1944 he was appointed asr Associate Park Naturalist in Yosemite National Park.r He transferred in 1933 to Petrified Forest National Monument, then to Zion National Park, Crater Lake National Park, and Glacier National Park, and back to Yosemite in 1944.r In 1951 he was head of interpretation at Zion and Bryce National Parks.r Besides this booklet, Walker wrote a studyr His specialty was paleontology.r While employed for the National Park Service he wroter of Triassic insects in Petrified Forest National Monument (1940),r where he also discovered vertebrate tracks.r He also wrote anr interpretative program study for Dinosaur National Monument (1943),r and Archeology of Zion Park (1955).r During 1955-1973 he was director of ther Division of Paleontology atr Fort Hays Kansas State College Museum.r

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r Walker married Wilda Opdyke in 1930.r They had one child, Margaret Jean Walker.r Wilda Walker died in 1980.r Myrl V. Walker died May 1985.r They are buried at Ft. Hays Memorial Gardens, Hays, Kansas.r In 1988 a series of paleontology papers were published asr “Articles in Honor of Myrl V. Walker,”r Fort Hays Studies, 3d ser. v. 10 (Science series).r

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Bibliographical Information

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r Myrl V. Walker (1903-1985),r Reptiles and Amphibians of Yosemite National Parkr (Yosemite: Yosemite Natural History Association, 1946)r “Special Number”r of Yosemite Nature Notes 25(1) (January 1946).r 48 pages. Illustrated. 24 cm.r Saddle stitched with yellow paper wrappers.r

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r Digitized by Dan Anderson, July 2005,r from a personal copy.r These files may be used for any non-commercial purpose,r provided this notice is left intact.r
r     —Dan Anderson, www.yosemite.ca.usr

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r r r r r r r r r r r r r r r r Reptiles and Amphibians of Yosemite National Park (1946), “Introduction,” by Myrl V. Walkerr r r r

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Yosemite Nature Notes

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r THE MONTHLY PUBLICATION OFr
r THE YOSEMITE NATURALIST DEPARTMENTr
r AND THE YOSEMITE NATURAL HISTORY ASSOCIATIONr

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VOL. XXVJANUARY, 1946NO. 1
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r REPTILES and AMPHIBIANSr

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r YOSEMITE NATIONAL PARKr

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r By Myrl V. Walker, Associate Park Naturalistr

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r INTRODUCTIONr

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r Numerous books, bulletins and notes have been published on ther Amphibians and Reptiles of North America, Western North America, and ther Pacific Coast. No effort has been made in this publication to present newr data, but rather to take the information already available and to apply it tor a rather restricted geographic unit in the Sierra Nevada region of California.r

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r The technical herpetologist may be disappointed when he finds that thisr bulletin has failed to indicate original authors and name changes by properr use of parentheses. He will also notice that a “middle of the road” courser has been followed in the selection of specific and sub-specific names. Nor attempt has been made in this bulletin to justify or defend the specificr names used, for such is not the primary purpose of this publication.r

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r The goal of this bulletin is to provide for the greatest number of people ar guide to the ready recognition of forms in a limited area, and furthermore,r to emphasize the value of the recognition of forms and their inter-relationshipsr as an influence in the maximum utilization of the interpretive recreationalr values preserved in such areas as our National Parks.r

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r ACKNOWLEDGMENTSr

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r To the University of California Press and the California Academy ofr Sciences special thanks are given for the loan of cuts, photographs, andr other assistance. The writer appreciates the assistance, counsel and guidancer of John R. Slevin, Joseph S. Dixon, Hector H. Lee, Robert C. Stebbins, Berthar Lutz, Leo F. Hadsall, William G. Hilton, C. P. Russell, C. Frank Brockman,r and all others who either assisted in securing cuts or gave of their time tor road and check the manuscript. To Park Photographer Ralph H. Andersonr special credit is due for his patience and skill in securing certain photographs.r

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r Interest in Reptiles and Amphibiansr

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r For the most part the averager person’s interest in reptiles and amphibiansr is negative rather thanr positive. Many people are far morer interested in the tall-tales commonlyr circulated about reptiles and amphibiansr than they are in their lifer habits, their relationships, or theirr economic value. Some people listenr with interest to the stories of joint-snakes;r snakes that swallow theirr young; hoop snakes, and milkr snakes, but their interest soon lagsr when they delve into these mysteriesr and find them vanishing one byr one— into thin air. Although wer know that toads do not cause wartsr just because they are handled, therer are some who still like to frightenr the children with this old whip ofr parental control, which may if over-worked,r develop into a phobia ofr considerable consequence. This latterr fact is often a great deterrent tor the proper understanding and appreciationr of this division of vertebrater animals, and causes many tor avoid even the casual study or observationr of this interesting group.r

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r Practically all young children showr little or no fear of snakes, but ratherr a genuine interest. This attitude isr certainly far different than the hystericalr behaviour of those who haver already developed a phobia becauser they have been frightened by olderr people.r

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r All snakes are carnivorous in theirr habits and therefore belong to ther group called “predators,” meaningr that they prey upon other animalr r forms. This fact is of great importancer in any study of snakes, for foodr supply is a limiting factor in theirr economic value, their abundance,r and their distribution. Although somer snakes are generally present in anyr given locality, their abundance orr scarcity is limited largely by ther three requirements: — temperature,r food and cover.r

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r A number of our snakes prey almostr exclusively on amphibians, sor in a study of this kind one soon realizesr the control effect of snakes onr toads, frogs and salamanders.r Changing conditions, such as ther draining of swamps or the disappearancer of wet meadows which resultr in a sudden drop in toad, frog orr salamander populations, will in turnr soon act to lower the number ofr snakes of certain species.r

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r The lizards are for the most partr less “disturbing” to the average personr than are the snakes, and sincer most of them have four legs and run,r rather than crawl, they occupy ar higher place in the scale of humanr tolerance. Few realize, however,r their economic value for they feedr largely on invertebrate forms, manyr almost exclusively on insects. Manyr lizards in turn serve as food forr certain snakes.r

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r The amphibians—toads, frogs andr salamanders—occupy a better placer in the scale of tolerance, althoughr there are some people who do notr hesitate to destroy even these harmlessr forms. Their economic valuer determined by this large number ofr r r r invertebrates, especially insects,r which they destroy. The amphibiansr are kept in control by the snakes andr other animals which prey upon them.r

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r The snakes are not without theirr natural enemies. Many snakes arer destroyed by carnivorous mammalsr and by birds of prey. Some hawksr are known to destroy many snakesr each season. The most recent andr perhaps the most devastating enemyr r of the snake is the automobile. Manyr snakes are killed by cars travelingr at high speed on asphalt surfacedr roads which retain heat at night andr thereby attract the snakes, or perhapsr the snakes are attracted by ther large number of rodents — groundr squirrels and mice—that have alsor fallen victim to this modern age ofr speed and motor car.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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AMPHIBIANS

r r The word amphibian is generally interpreted as meaning “two-lives,” andr as applied to the salamanders, toads, and frogs, we usually visualize theser forms as living the first life in water, the second life on land. The first lifer is called the larval or tadpole stage and is ordinarily spent in the water.r There the larva breathe mainly through gills; they are without legs in ther first stages, and have a peculiarly flattened tail which propels them throughr the water. When these larva mature we expect them to lose their gills, growr some legs, and in the case of toads and frogs, to absorb their swimming tails.r

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r These generalizations may be wholly acceptable, but when we study ther amphibians more carefully we find that various forms have made short-cutsr or have decided to shorten one or the other of their two lives, so as to enabler them to survive in what would otherwise be an unfavorable environment..r

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r The amphibians are divided into two groups, one possessing and retainingr tails throughout their entire life (the tailed amphibians), and the second (ther tailless amphibians) which are without this appendage in the adult stage.r The salamanders belong to the former, the toads and frogs to the latterr division.r

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r Amphibians are usually distinguished from the reptiles by the fact thatr they have a moist skin which may be either slimy or warty, but in no caser do they possess dry scales. For all general purposes this will serve tor distinguish these two groups of vertebrates.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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SALAMANDERS

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r The name salamander probably brings to the average mind one of twor thoughts; either a slimy, creeping creature, very repugnant and to be avoided,r or stories of fire-loving amphibians that emerge from the flames very unexpectedly.r Those who are interested in. the confusion brought about byr common names know that the name salamander has been used rather freely,r even being applied to certain mammals (gophers or moles) in some of ther southern states.r

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r Salamanders have for the most part a very smooth and moist or “slimy”r skin. They are amphibians and many species spend a portion of their lifer in water (larval stage), but when mature they usually leave the water andr live on land but not on dry land. Their body processes are dependent uponr a certain amount of moisture, so their skin must always remain moist orr slimy; and for that reason they are to be found only in moist or damp habitats,r under rocks, near streams or ponds, in dead or decaying logs, in caves orr crevices in the rocks. Furthermore, some species of salamanders are knownr to give off a slimy secretion, especially when handled or irritated. Thisr secretion may be slightly poisonous or distasteful to certain of their enemies,r but it does not ordinarily affect man unless it reaches delicate membranesr such as in the eyes.r

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r The association of salamanders with fire is not without some significance,r for undoubtedly many of the pioneers, in addition to the ancients, werer occasionally struck with awe to see salamanders crawl from burning logsr in the fire place. These observers were not aware that certain salamandersr live under the bark of rotten logs, or within the moist center of the rotten logr itself. Probably the salamander was just as surprised as his human observerr to find himself suddenly subjected to a rapid increase in body temperature,r and perhaps his only thought was to depart from his improperly selectedr abode and to locate a more moist and cool situation for a retreat.r

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r It is unfortunate that so many people have developed a fear of salamanders.r Many seem to have only the one desire—that is, to “kill the slimyr creature.” All salamanders are harmless as far as human beings are concerned.r Moreover, they are of considerable economic value because of ther large numbers of insects, spiders, and larvae that they destroy in securingr their food. They are worthy of some protection. On the other hand it is fortunater for the salamanders that so few are ever seen by man. Their habit ofr retreating to the moist or damp situations, under rocks, logs, or in caves orr crevices, seems to give them a certain degree of security. Few people, exceptr experienced collectors are aware of the fact that fairly large numbers ofr salamanders are present in many localities. They are sometimes foundr where conditions appear rather unfavorable.r

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r Another reason salamanders are seldom seen by the average person isr because twice each year certain forms are forced to retreat from the surfacer due to seasonal change. Some hibernate, disappearing from the surfacer with the beginning of cold weather. These may burrow down into the soilr or retreat downward in cracks in rocks or logs to a point where they avoidr freezing temperatures. Others retreat in a similar fashion during the later summer and early fall months, especially in regions where there is a longr dry or extremely warm period. This summer retreat is called aestivation,r and it carries them over until the fall rains make it possible for them to mover around freely when moisture is again abundant for their sensitive thin skins.r

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r Only three species of salamanders have thus far been collected from withinr the boundaries of Yosemite National Park, although at least two othersr approach quite closely and may someday be taken within the Park.r

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r The great divergence in adaptations and habitats of the three forms foundr in this area is most interesting. Only one possesses lungs, the other two arer without normal lungs. Only one lays its eggs in water. There they hatch andr the young pass through a larval stage with feathery gills, a stage requiringr several months. One spends most of its time under or inside moist, dampr and rotten logs, and never even goes to water to deposit its eggs. Althoughr not definitely known, it is believed that the eggs are laid singly or in clustersr and attached to the underside of old damp logs. There the young pass entirelyr through their larval stage within the egg and emerge as fully developedr but immature young. This form seems peculiar in not possessing lungs,r although it lives entirely on land. The third species is even more stranger than the other two for it lives far from either water or logs, usually under flatr rocks where there is damp soil, yet it possesses no lungs. There is a possibilityr that this form does not lay eggs and that the young are broughtr forth alive, fully developed, but small and immature.r

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r A brief description of each of these salamanders is given in the followingr paragraphs; however, those who are particularly interested should readr some of the references listed at the end of this publication.r

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SIERRA NEWTr
r Triturus sierraer

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r The Sierra newt, often commonlyr called water dog or mud puppy, isr probably the most common salamanderr found in Yosemite National Park.r This is due largely to the fact thatr this salamander returns to the waterr each year to lay its eggs and causesr the individuals to become fairlyr abundant in the vicinity of goodr water holes or ponds. When ther young hatch they are typical larvaer with feathery gills. They must remainr in the water a year or so beforer they develop to the point where theyr can leave the water and live on land.r

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r The Sierra newt is about sevenr inches in length when full grown;r however, the tail accounts for aboutr half of this length. The color of ther back and sides is a chocolate-brownr to burnt umber, sometimes very dark,r but the underside is in sharp contrast,r being either burnt orange or in somer instances a shade of light red. Thisr species is never spotted and is easilyr distinguished from the other salamandersr in this area.r

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r This species and some of its closer relatives are quite unique among ther salamanders since the skin of individualsr living on land away fromr water actually becomes rough, duer to the development of many tinyr wart-like tubercles, but when theyr return to the water for depositingr eggs, the skin again becomes smoothr and slimy.r

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r A few newts have been taken onr the floor of Yosemite Valley, alongr the road below the Wawona Tunnel,r and near Fern Spring; however, mostr of our collection came from the vicinityr of Swamp Lake, Vernon Lake,r r r

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r r SIERRA NEWTr
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r r r Laurel Lake, and in the Miguelr Meadows. This may not be a truer index of distribution but rather a resultr of conditions favorable for collecting.r

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r SIERRA NEVADA SALAMANDERr
r Ensatina sierraer

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r The Sierra Nevada salamander isr the only spotted salamander foundr within the boundaries of Yosemiter National Park. The general bodyr color is blackish or deep brown onr the back and sides, but with manyr large and small irregular spots orr blotches of dull orange to oranger yellow. The underside of the bodyr is a fairly uniform pale slate fadingr to gray on the tail. The adults averager about five inches in length.r

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r These salamanders are interestingr r due to the fact that, although theyr seldom go near pools of water butr live entirely on land, they have nor lungs. Furthermore, they do not depositr their eggs in water, but presumablyr lay them singly or in smallr r clusters which are attached to ther underside of damp or rotten logs andr bark. If like a closely related speciesr the females will sometimes remainr and either stand guard or actuallyr curl their tails around the cluster,r perhaps to aid in keeping the eggsr moist by means of glandular secretions.r Some observers believe thatr the eggs are well advanced in developmentr before they are deposited.r The young do not spend a larvalr stage in water, but pass through thisr entire stage within the egg andr emerge as fully developed but immaturer forms.r

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r It seems a bit strange that thisr salamander, which never spendsr any portion of its life in water, shouldr have such a very fine, delicate,r smooth and slimy skill. But when itr r r r r sacrificed its lungs it became necessaryr that it do a certain portion of itsr breathing through the skin. It mustr always stay where sufficient moisturer is available to keep its skinr moist. These forms are usually foundr under the damp and moist bark of oldr rotten or decayed logs, beneath ther logs themselves, or occasionally inr cavaties within the rotting logs.r

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r This salamander has a peculiarr constriction near the base of the tailr which makes it possible for the animalr r r

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r r r to readily release its tail whenr attacked by an enemy. The enlargedr portion of the tail contains poisonr glands which secrete a fluid thatr probably serves to protect these salamandersr to a certain degree.r

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r Although nowhere abundant, theser salamanders appear to be widespreadr over the Park below 7500r feet. They have been taken on ther floor of the Valley, above Inspirationr r Point, at Wawona, in the Mariposar Grove, in Miguel Meadows, and inr the Hetch Hetchy Valley.r

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r MOUNT LYELL SALAMANDERr
r Hydroinantes platycephalusr

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r Of all the forms of vertebrate lifer found in Yosemite National Park,r probably no other is so well knownr to the scientific world, yet so littler known to the average Park visitor, asr this very strange species of salamander.r It was not known to scientistsr r r until 1915 when the first two specimensr were accidentally caught in ar mouse trap at a camp near the baser of Mount Lyell. It was nearlyr twenty years later before anyoner learned of its abundance within ther Park. Even today there is still muchr to be learned of its life history.r

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r The Mount Lyell salamander is ther smallest of the three species ofr salamanders found here, being lessr r r r than five inches in length when fullyr mature. They are a general darkr chocolate or slate color on body andr sides but with many lighter markingsr throughout the dark except on ther underparts back of the throat, whichr is a uniform dilute chocolate to slate.r The head appears to be quite broadr r r

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r The Mount Lyell salamander differsr from the more common salamandersr by not possessing lungs, and inr being able to live far from ponds orr water. It is presumed, that like ar European relative, it does not depositr eggs, but rather the young are bornr alive. Its isolation along the westr slope of the Sierra Nevada mountainsr is indeed significant, for its nearestr relatives are found—not in the Newr World—but in Italy and France ofr the Old World.r

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r During the past few years thisr r salamander has been taken at widelyr separated localities in Yosemite Nationalr Park; however, most of ther specimens came from above 7000r feet in elevation. Due to the fact thatr they are in no way dependent onr running water, pools, or fallen andr decaying logs, but are found underr r flat rocks that are resting on soilr kept wet by seepage water, manyr times by melting snow water, theyr are found in such unexpected placesr as on the very top of Half Dome. Ar regular “colony” make their homer under the flat rocks in the little valleyr on top of Half Dome, where the snowr field lasts well into July, and wherer they are kept moist by the cold snowr water seeping along in the soil beneathr the flat rocks. More Mountr Lyell salamanders have been collectedr from the top of Half Dome thanr from any other simile locality inr Yosemite National Park.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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TOADS

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r Nearly everyone is acquainted with our common toads. The toads haver become quite tolerant of civilization and have found the garden a good placer to secure food and with the necessary moisture to keep their warty skinsr functioning properly in the process of respiration. The gardener is also wellr aware of their economic value, for he has no doubt seen them snap up manyr bugs, beetles, and other pests of the garden. Often they gorge themselvesr until they are hardly capable of hopping, but instead their movements arer limited to an awkward crawl.r

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r Although their warty skin helps to prevent loss of body moisture, they arer still somewhat limited in their range. They are more active at night than inr the day time. They spend most of the day in a small burrow or shelter thatr they have formed by literally “backing down” into the moist soil. The toadsr have a sharp tubercle on the inner sole of the hind foot that assists themr greatly in this backward digging activity.r

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r The adults live on land, often some distance from water, but once eachr year they return to the ponds and streams to deposit their long double-strandr string of eggs. Here the young tadpoles (larva) hatch and for some time liver in the water very much like a fish, for they have only gills—no lungs or legsr —in the tadpole stage. Some toad tadpoles require several months to growr up and do not acquire their legs or lose their tail until the next summerr season rolls around.r

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r In all areas where seasonal variations are severe, the toads hibernate inr the winter time, burrowing down in the soil, in old gopher roles, or in cracksr alongside buildings, until they reach a point where they are safe from frostr and freezing weather.r

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r Although toads have warts, they do not cause warts to grow on humanr hands that touch them. The warts on the toad help him to conserve his skinr moisture, and secondarily may secrete a substance that is somewhat poisonousr if taken internally, or if it touches delicate membranes like those in ther eyes; but on the hands it is generally harmless. Any dog that makes ar mistake and takes a toad in his mouth suffers for his foolishness. This secretionr seems to afford the toad some measure of protection.r

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r Toads have also developed a rather large bladder-like organ which isr used for water storage. This is something that the toad can draw upon tor keep his skin moist if he gets too far from moist soil or leaves. The almostr clear, colorless liquid often discharged by toads when first picked up is thisr supply of storage water, for its weight often greatly hinders the movementsr of the toad. He simply lightens his load by discharging this water, which hasr absolutely no poisonous or irritating properties.r

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r Only two species of toads are found in Yosemite National Park. They arer usually easily distinguished, not just because of their color variation and size,r but because they each occupy a particular altitudinal range or habitat.r

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r CALIFORNIA TOADr
r Bufo boreas halophilusr

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r r CALIFORNIA TOADr
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r CALIFORNIA TOADr
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r This large toad is commonly foundr in Yosemite Valley and other areasr in the Park at comparable elevations.r It does not appear to live above 4,500r feet in elevation, so that there is anr unoccupied space of nearly 2,000r feet, that is, between 4,500 and 6,500r feet where few if any toads are found,r for the other species of Bufo, ther Yosemite toad, does not descend tor elevations below 6,500 feet.r

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r The California toad has a muchr heavier body than the Yosemite toad;r in fact, they are so bulky that theyr seldom hop as do most toads, butr instead move forward in a most interestingr slow awkward crawl. In ther daytime they hide under boards orr fallen logs, under flat stones, or evenr occupy the open burrows of fieldr r mice or ground squirrels. At nightr they come out to feed, and are oftenr seen under the street lights wherer they have been attracted by the larger number of insects which often gatherr around the lights.r

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r These large toads have sufferedr greatly because of our modern age.r The asphalt surfaced highwaysr which retain many small pools ofr water after light summer showers,r especially evening showers, seem tor attract many toads. Here they arer killed by the hundreds because withr their slow awkward crawl they cannotr escape the wheels of the motorr cars that dash down the roads atr terrific speed.r

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r YOSEMITE TOADr
r Bufo canorusr

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r This small toad with its peculiarlyr rounded parotoid glands and stranger sexual dimorphism has been foundr thus far only in or near the Yosemiter National Park. Within the Park itsr range seems to be very limited, thatr is, to areas at or above 6,500 to 7,000r feet, and only in wet meadows. Ther Yosemite toad was first discoveredr by members of the University of Californiar r r

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r r YOSEMITE TOADr
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r YOSEMITE TOADr
r r r scientific expedition when theyr were making their study of the faunar of the Yosemite National Park regionr in 1915.r r r r The Yosemite toad differs from ther California toad in many respects.r They are considerably smaller, theyr have fewer and smaller “warts,” andr they have a very peculiar springr song, a long melodious trill, hencer their specific name canorus. As theyr live at high elevations where the wintersr are long and snow remains onr the ground for several months, theser toads must hibernate for five or sixr months each year. They appear tor be solitary at all times except duringr the spawning season when bothr males and females may be foundr near pools in the larger meadows.r

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r Yosemite toads in our collectionr have come from near Mount Danar at 10,000 feet elevation, Researchr Reserve at 8,300 feet, Kerrick Meadowr at 9,300 feet, Slide Canyon at 10,000r feet, Lyell Base Camp at 10,400 feet,r Virginia Canyon at 10,000 feet, andr near Upper McCabe Lake at 10,600r feet.r

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r r r r r r r r r r r r r r r r r r Reptiles and Amphibians of Yosemite National Park (1946), “Tree Toads,” by Myrl V. Walkerr r r r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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TREE TOADS

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r Another of our interesting amphibians is the small tree-toad or tree-frogr which is so often heard but seldom seen by the average person. Althoughr the tree-toad is the smallest of all the amphibians found in Yosemite Nationalr Park, it is, nevertheless, one of the most interesting. The tree-toad does notr spend all its life in trees, as one might infer from the name. Instead the tree-toadr must go to ponds and streams to deposit eggs which hatch into tinyr tadpoles that spend two or three months in the water before being able tor maintain themselves on land. Of all our toads and frogs, the tree-toad is ther only one equipped with the necessary tools to climb up into trees or bushes.r This it does quite often as an adult and it may occasionally be found sittingr on a leaf patiently waiting for some insect to come along. This special equipmentr consists of small round sucker-like discs which it has on all its toes,r both fore and aft, and these make it possible to climb with ease; in fact, itr seems to delight in walking up the glass panes of the aquarium jar, and out,r if the cover is not always kept in place.r

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r But the most interesting feature, as far as our amphibians are concerned,r is the fact that it can change skin color to match the color of the background;r hence, it is quite inconspicuous among the low leaves of vines or shrubs.r Only when it visits the water holes in the spring, or after sudden rain storms,r are we aware of its presence, but at that time it puffs out its throat and singsr a song no one can mistake, a non-melodious “crack-it” which is all out ofr proportion to the size of the individual making the noise.r

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r Although the tree-toad is an expert in the art of camouflage, there is oner color feature of its anatomy that seems to change very little, and that is ther dark black line or bar that extends from the snout through the eye and backr through the ear membrane nearly to the shoulder. This tell-tale mark is alwaysr present for ready identification of the little tree-toad.r

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r PACIFIC TREE-TOADr
r Hyla regillar

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r In one respect the Pacific tree-toadr differs from all other of our amphibians,r for it seems to pay no attentionr to life zones, changes in elevation orr forest cover, but is found from ther lowest elevations in the park up tor over 10,000 feet. No other amphibianr has been able to adapt itself to suchr r r

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r r PACIFIC TREE TOADr
r [click to enlarge]
r
r From Slevin: The Amphibians of Western North America. Courtesy of the
California Academy of Sciences
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r PACIFIC TREE TOADr
r r r r divergent life zones or habitats. Evenr in areas where conditions seem to ber extremely arid, it manages to absorbr enough moisture from the earlyr morning dew, or from the leaves andr foliage, so as to keep its skin moistr and functioning properly.r

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r The tree-toad is small and usuallyr measures less than two inches inr length, and is always readily recognizedr by the small rounded discs onr the ends of all toes. The color isr variable, being gray, green, or nearlyr r black. The underside is less variable,r being nearly white and unspotted,r but with a blackish patch on ther throat of the males. They are usuallyr found singly except during ther spawning season.r

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r Tree-toads have been taken on ther floor of Yosemite Valley, in the poolsr along the Merced River, and evenr around the houses where watering ofr r lawns and shrubs provides an attraction.r They have been taken atr Tuolumne Meadows, Yosemite Researchr Reserve, Lukens Lake, Yosemiter Falls, Miguel Meadows, andr even on the back porch of the Museum.r They seem to be abundantr nearly everywhere, but it takes quick,r keen eyes and a little knowledge ofr tree-toad habits to be able to locater them at the various seasons of ther year.r

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r r r r r r r r r r r r r r r r r r Reptiles and Amphibians of Yosemite National Park (1946), “Frogs,” by Myrl V. Walkerr r r r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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FROGS

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r The frogs, unlike the toads and tree-toads, must always remain close tor permanent pools of water. Although their skin allows them to leave ther water temporarily and to bask on floating logs or debris, they must ever sor often moisten themselves by plunging into the pool. When it comes to ther matter of protection, frogs are far more dependent on pools of water thanr are the toads and tree-toads, for they escape from most of their enemies byr diving into the water and hiding either under rocks, or going down to ther bottom of the pool where they either partially or completely bury themselvesr in the muddy ooze and are lost to the sight of most enemies.r

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r Unlike the toads, they are not warty nor do they carry an extra supply ofr water with them. They do not have digging tools on their hind feet, nor haver they developed any poison glands comparable to the toads. They are farr more at home in water than on land, and their long hind legs push themr through the water with remarkable speed.r

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r Nearly everyone has at some time or another seen the large jelly-liker masses of frogs eggs in quiet streams or pools, and upon returning a few daysr later, noticed the great number of tiny tadpoles. In the warmer regions theser larva mature at the end of the first summer, but in the higher and colderr elevations, where the summer seasons are short, they pass the first winter asr tadpoles, becoming adults some time the second summer.r

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r Three species of frogs are found in Yosemite National Park, although oner form is confined to the lower elevations. One of these frogs reaches sufficientr size to be considered of some value for food, and outside the Park these frogsr have sometimes been collected in large numbers and furnished to the markets.r The other two frogs found in the park are much smaller and are ofr economic value only because of the number of insects or insect larvae theyr destroy, or in their value as fish food. It has been found that trout in ther higher mountain lakes and streams feed heavily on the small frog tadpoles,r and in many instances, sooner or later, almost eliminate the frogs from theser lakes.r

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r CALIFORNIA RED-LEGGED FROGr
r Rana aurora draytoniir

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r r CALIFORNIA RED-LEGGED FROGr
r [click to enlarge]
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r From Slevin: The Amphibians of Western North America. Courtesy of the
California Academy of Sciences
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r CALIFORNIA RED-LEGGED FROGr
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r The California red-legged frog isr by far the largest frog found in ther Yosemite National Park. They sometimesr measure four or five inches inr length. The adults may be readilyr identified by the red and pink markingsr on the underside and inner sider of the big hind legs. They are lightr to dark hi-ewe above and with larger or small black spots on the dorsalr surface and on the thighs. They appearr to be much more hump-backedr than the other two species of frogsr found in Yosemite.r

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r The red-legged frog seems to showr a preference for the big ponds alongsider streams that are filled to theirr maximum during the high water andr flood stages in the spring. They seemr to he more of a pond or lake frog,r r r r rather than a stream frog, and seldomr are found in association with swiftlyr running water.r

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r The California red-legged frog doesr not appear to be very abundant inr Yosemite National Park, and thusr far has been found only in the lowerr elevations: in fact, our first museumr r r accession of this frog was not mader until 1938 when specimens werer taken at Swamp Lake. Other specimensr have since been taken inr Miguel Meadows and Sand Pit Lake.r Perhaps careful collecting will prover that this frog is more widespreadr than our records thus far haver seemed to indicate.r

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r YELLOW-LEGGED FROGSr
r Rana (See key for species)r

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r r CALIFORNIA YELLOW-LEGGED FROGr
r [click to enlarge]
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r Photo courtesy Calif. Acad. of Sci.r
r CALIFORNIA
YELLOW-LEGGED FROGr
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r These two species of frogs appearr to be so closely related that it seemsr unnecessary to treat them separately;r r hence they are discussed only in ar general manner. They are moderater sized frogs with an average lengthr of three inches or less. They arer blackish, dark green or brown above,r and with a few rather indistinctr markings. The markings on ther underside are more distinctive, beingr r yellow or whitish, with the yellowr underside of the hind Legs being theirr most diagnostic characteristic. Ther r r r most apparent characteristics whichr distinguish the two species are asr follows:—The California yellow-leggedr frog has an ear membrane whichr is quite rough and with a “pebbled”r texture; the hind leg is rather long,r and in addition this frog lives largelyr below 6,500 feet in elevation. Ther Sierra yellow-legged frog has an earr membrane which is relativelyr smooth, not pebbled; the hind leg isr only moderately long, and they liver at elevations mostly above 6,500 feet.r

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r The range of the California yellow-leggedr frog, especially in ther lower elevations, allows it to remainr active throughout the entire year,r but the Sierra yellow-legged frogr must hibernate for long periods eitherr along the shore lines or in ther bottom of muddy pools and lakes inr the high alpine country. Theser streams and lakes are sometimesr almost completely frozen for severalr of the mid-winter months.r

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r r SIERRA NEVADA YELLOW-LEGGED FROGr
r [click to enlarge]
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r Photo courtesy Calif. Acad. of Sci.r
r SIERRA NEVADA
YELLOW-LEGGED FROGr
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r The yellow-legged frogs are probablyr the most common amphibiansr of Yosemite National Park, especiallyr in the vicinity of streams, pools, andr lakes; and furthermore, they ranger from the lowest elevations up tor 11,500 feet where specimens haver been taken in the small lake nearr the base of Mount Lyell. They arer r r of course most abundant alongr stream banks and lake shores asr all fishermen and hikers are wellr aware, not because they see ther frogs, but rather because they hearr them as they “plunk” into the water,r one after another, to find shelter andr protection.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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REPTILES

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r The few reptiles that live in the world today are but a small remnant ofr a once mighty race or division of our vertebrate animals. Those people whor today are frightened at the sight of a little garter snake or spiny lizard wouldr have been shocked beyond description had they met face to face some ofr the giant dinosaurs or other reptiles of the ancient past. Even if such a meetingr had occurred, there is little doubt but that most of the reptilian giantsr would have been little interested in their human observers. Many of ther ancient reptiles were for the most part herbivorous and subsisted on plantr life. Only in recent times (geologically speaking) and in a last effort to maintainr their race, have the majority of reptiles become carnivorous or flesh-eaters,r rather than herbivorous.r

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r If we could but piece together each and every adaptation made by ther r r r reptiles of the past in their effort to secure food, find shelter, and reproducer their kind, we would unravel in detail a most marvelous story. This storyr would tell us why snakes have lost their legs, why some lizards are legless,r blind, and burrowing, why some lizards are covered with spines, and whyr some snakes have developed a poison apparatus for use in securing theirr food.r

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r Taken all in all, the reptiles have not been outstandingly successful inr their efforts to maintain themselves, and those few forms that we still haver with us today are all the more interesting because of their varied and oftenr seemingly useless variations, habits or adaptations. We often wonder whyr some reptiles are so brilliantly colored, why some reptiles “play dead,” andr why some reptiles spread their heads. And again why do some reptilesr vibrate their tails, and why have other reptiles developed a rattle on ther end of that vibrating tail.r

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r Generally speaking, reptiles may be identified by the fact that their bodyr covering is composed of rather dry scales, easily recognized in most commonr snakes and lizards, but somewhat modified in the turtles and tortoises.r They differ from the mammals and birds, above them in the scale of life, byr having “cold blood” and thereby. being restricted in their habitats by ther temperature of their surroundings. They rank above the amphibians andr fishes since they are far less dependent on water. They have no larvalr stage, and the development of their bony skeleton, especially their skullr and jaws, often set with firmly attached teeth, is a specialization which distinguishesr them from the amphibians.r

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r It is unfortunate that there is not a more genuine interest in the study,r observation and recognition of reptiles—snakes, lizards, and turtles. Manyr of these forms are not difficult to capture, and are easily kept in captivity;r however, they should be kept in captivity only if the observer is conscientiousr in his efforts to secure worthwhile information on their behaviour andr food habits. Our reptiles in general are just as worthy of adequate protectionr as are the mammals and birds, and the harmless forms should be consideredr an integral part of the biotic picture of any community. The fewr poisonous forms that do exist should be studied carefully so that they mayr be readily identified and their real danger recognized. Only when theirr presence may actually constitute a danger to human life should we tolerater the selective destruction of these forms that otherwise are of economic valuer and a part of the balance of nature.r

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r Although representatives of each of the three different divisions of reptiles—turtles,r lizards, and snakes—are present in the Yosemite Nationalr Park, their numbers are somewhat limited. Only one turtle has been recordedr from this region. The lizards are more numerous with nine species present,r and at least thirteen different snakes have thus far been collected withinr the boundaries of the Park.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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TURTLES

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r The turtles and tortoises are very poorly represented in the reptilian faunar of the Pacific Coast, and only one species reaches the Yosemite Nationalr Park area.r

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r This group of reptiles is well known to nearly everyone, for their veryr specialized protective shell is a feature not found in any other of our Americanr reptiles. The scaly body covering of the reptile division is still plainlyr seen, especially on the legs; however, the upper and lower shells, commonlyr called carapace and plastron, are so modified that their scale characteristicsr are practically lost.r

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r Like most of the other reptiles they possess sharp claws on their toes, ar feature which helps to distinguish the reptiles from the amphibians. Theirr jaws are quite unlike the lizards or snakes for they do not possess teeth, andr furthermore, the jaws are modified into a type of beak.r

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r A majority of the turtles and tortoises have not ventured far from water,r but a few have managed to exist on land, some actually going so far asr to adjust even to the arid deserts of the southwest. All seem to be ratherr variable in food habits, with both animal and plant food being taken. Thoser forms that live in ponds or streams secure their food either in the water orr near the water’s edge, and some even seem to be unable to swallow unlessr the head is submerged beneath the surface of the water. For protection ther pond and stream types dive to the bottom of the pond either to partly buryr themselves in the mud, or to become lost to view in the depths of the water.r

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r In regions where winter temperatures drop rather low, turtles may hibernater during the coldest winter months. In common with many of the reptiles,r they deposit eggs that have a very leathery shell. These are buriedr in sand or decaying vegetable matter where incubation takes place, ther parent showing no interest in the young.r

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r Unfortunately, perhaps, because of the brightly colored shells of the youngr of many species of turtles, these tiny specimens are now handled in the petr shops and each year are sold by the thousands. Because so few peopler know or seem to care about them, after the novelty has worn off, they arer often left to starve, or in many instances, are gently dropped out the backr door. A number of the latter find their way to ponds where they soon establishr themselves, so that today the naturalist can never be sure that ther turtles he observes in the ponds and streams are native there, or whetherr man has been involved in their unnatural distribution.r

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r WESTERN POND TURTLEr
r Clemmys marmoratar

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r The western pond turtle is foundr only in the lower elevations alongr the western boundary of the Park,r r and to date has been collected onlyr from the vicinity of Swamp Lake,r near Eleanor Dam, and in the Miguelr Meadows. These turtles arer fairly abundant at lower elevationsr r r r in the San Joaquin Valley.r

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r This turtle is only about eightr inches long when fully mature. Ther top shell (carapace) is dark brownr or blackish in color, but each individualr plate is marked with yellowishr spots or lines, the latter sometimesr tending to radiate from ther center of the plate. The plates of ther carapace are relatively smooth, notr roughened. The individual plates inr the undershell (plastron) are mainlyr yellowish in color but are often borderedr with black. The legs, headr and neck are generally brownish,r but often spotted with black orr yellow.r

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r These turtles are difficult to observer because they seem to diver into the water at the slightest disturbancer r and remain submerged forr some time. They crawl out on logsr or rocks that project above the surfacer of the water and there sunr themselves for long periods unlessr disturbed. Fishermen are often surprisedr to find that these turtles willr take a small hook baited with meatr or worms. These turtles are sometimesr utilized for food, and occasionallyr will be found displayed inr the markets along the Pacific Coast.r It is doubtful if many visitors willr ever see this turtle, for its habits andr the fact that its range is limited inr Yosemite causes it to be one of ther least seen of our reptiles, except ofr course, for some of the nocturnalr snakes.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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LIZARDS

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r If we were to ask the average person how he distinguished the lizardsr from the snakes he would probably reply that the lizards are reptiles whichr have four legs and can run over the ground, while snakes are legless andr only crawl. This happens to be true for the lizards found in Yosemite Nationalr Park, but in other sections of the United States there are legless lizards,r lizards with only two legs, and lizards that are not only without legs, butr in addition are blind and burrowing. A more careful observation of lizardsr and snakes will reveal that the lower jaw bones of all lizards are solidlyr joined in front, while in the snakes the lower jaws are held together by ar somewhat elastic type of cartilage. A further difference which may be observedr between the lizards and snakes of Yosemite is that the lizards haver eyelids which they can close over the eye, while the snakes are withoutr these movable eyelids. This distinction does not hold true in other sectionsr of the United States.r

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r A majority of the lizards deposit eggs which are left to hatch without furtherr attention from the parent; however, a few lizards produce their youngr alive. Included in this latter group are some of the horned lizards, commonlyr but erroneously called horned toads.r

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r Nearly everyone is well acquainted with the fact that a number of ther lizards easily break off or “throw” their tails when roughlyr handled or pursuedr r r r by an enemy. This seems to be a method of self preservation and doesr no particular harm to the lizard, for it will in time proceed to grow anotherr tail, although the new member may be slightly smaller and with scalesr more variable in size and character.r

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r Although some of the lizards are herbivorous, they are for the most partr insectivorous and few people ever stop to realize their economic value inr the control of insect pests. All forms found in Yosemite are prolific insectr eaters and are active mostly during the daylight hours. Lizards are coldr blooded and must of course hibernate during the cold winter months whenr temperatures drop below certain levels of tolerance.r

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r Lizards are very interesting and are easily studied, but they are difficultr to maintain in captivity for any great length of time. Many will attempt tor bite if roughly handled, and their small sharp teeth may puncture the skinr and draw blood, but otherwise they are harmless. In fact, the only poisonousr lizard in the entire United States is the Gila monster which is found inr the arid and desert regions of the southwest.r

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r The different species of lizards are not so abundant in Yosemite National.r Park as they are in areas that are warmer and more arid, so that we arer able to list only nine species native to this area. Even one of those mayr have reached the park as a result of being introduced by man.r

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r THE SPINY SWIFTS, FENCE LIZARDSr
r OR BLUE-BELLIED LIZARDSr
r Sceloporus (See key for species)r

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r In Yosemite everyone is aware ofr the existence of a number of smallr lizards commonly called by suchr names as spiny swifts, scaly lizards,r fence lizards, or blue-bellied lizards.r They belong to the genus Sceloporusr and because they are so much aliker few people ever try to distinguishr the different forms. For that reasonr no attempt is made to discuss eachr species separately but all are consideredr in a general manner.r

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r Four species of Sceloporus arer found in Yosemite National Park.r Three of them are closely relatedr and are grouped into the blue-belliedr lizard division, while the other oner is commonly called the mountainr lizard, although perhaps a betterr r name might be brush lizard. Ther name blue-bellied lizard is of courser descriptive and refers to the bluer under-markings so characteristic ofr this form. The name fence lizard isr applied to one species because cfr its interesting habit of congregatingr in the vicinity of or on rail or logr fences. Here these lizards climbr about either to sun themselves or tor secure certain insect food.r

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r The three species of blue-belliedr lizards seem to have each selectedr a particular niche in the Yosemiter region. The western fence lizard isr found in the lower elevations on ther western side of the Park, up to andr including the floor of Yosemite Valley.r The Pacific blue-bellied lizardr tends to occupy the space abover the fence lizard, that is, from the Yosemiter Valley up to and includingr r r r r r

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r r Upper: WESTERN FENCE LIZARD  Lower: PACIFIC BLUE-BELLIED LIZARD r
r [click to enlarge]
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r From Slevin: The Amphibians of Western North America. Courtesy of the
California Academy of Sciences
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r Upper: WESTERN FENCE LIZARD
Lower: PACIFIC BLUE-BELLIED LIZARDr
r r r r r the areas with elevations comparabler to the rim of the canyon. Here itr shares this zone with the mountainr lizard; however, the latter is definitelyr an underbrush or ground form,r while the former is at home amongr the big talus boulders or on ther rough rocky areas at this elevation.r

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r The third species of blue-belliedr lizard, the Tenaya blue-bellied lizard,r is a large form occupying a ratherr limited and restricted zone ofr higher elevation in the vicinity ofr Merced Lake, Washburn Lake, Tenayar Lake and Glen Aulin. It is apparentlyr well adapted to the openr and well lighted areas of glaciallyr polished rocks at this elevation. Thisr last species is of particular interestr in view of the fact that Yosemiter National Park has been designatedr as the type locality for this form.r

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r The Sceloporus lizards are allr small, the mountain lizard seldomr reaching a length of five inches.r The blue-bellied lizards are larger,r being from six to eight inches inr length, with the body averagingr from three to four inches and ther tail from three to five inches. All arer covered with small scales and ther dorsal scales usually have a ridger or “keel” running down the centerr of the scale which ends in a shortr but sharp projecting spine. This isr soon discovered when one attemptsr to rub them the “wrong” way.r

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r The Sceloporus lizards, like manyr of the other lizards, have that abilityr to break or throw their tails whenr attacked by an enemy, and to regenerater or grow a new tail just inr case such an emergency might ariser r again. These lizards are of economicr value because of the larger number of insects they destroy. Butr they are in turn preyed upon byr several of the snakes and by somer of the hawks, owls, and shrikes.r

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r CALIFORNIA HORNED LIZARDr
r Phrynosoma blainvillii frontaler

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r The small horned lizard, morer commonly called horned toad, seldomr exceeds three to four inches inr total length. It is probably betterr known to the average person thanr any other of our North Americanr lizards. Its flattened form and peculiarr appearance with its set of tinyr sharp pointed horns are so distinctiver that it is usually recognized atr a glance.r

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r It ordinarily dwells in the morer open, arid, rocky and sandy areas,r and where the temperature remainsr rather warm. Few places in Yosemiter offer the ideal habitat for thisr lizard, and although a few specimensr have been taken on the floorr of the Valley, it is questioned whetherr or not these should be consideredr valid records. It is feared thatr the specimens might have been carriedr in by some tourist who, laterr tiring of the “pets,” turned themr loose in the Valley where they werer able to maintain themselves longr enough to be observed by severalr people, and occasionally recapturedr and added to the research collection.r

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r These small lizards feed on a varietyr of small insects, especiallyr ants, and for that reason they arer easily kept in captivity. They willr soon become very tame and willr r r r r

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r r Upper: SAN DIEGO ALLIGATOR LIZARD WESTERN SAN DIEGO ALLIGATOR LIZARDSAN DIEGO ALLIGATOR LIZARD  Lower: CALIFORNIA WHIP-TAILED LIZARD r
r [click to enlarge]
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r From Slevin: The Amphibians of Western North America. Courtesy of the
California Academy of Sciences
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r Upper: SAN DIEGO ALLIGATOR LIZARD WESTERN SAN DIEGO ALLIGATOR LIZARDSAN DIEGO ALLIGATOR LIZARD
Lower: CALIFORNIA WHIP-TAILED LIZARDr
r r r r even take small insects such as fliesr or beetles from the fingers. Althoughr they often live in very aridr regions, they will take water readilyr when in captivity.r

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r Unlike some of the other hornedr lizards, this species deposits eggsr instead of producing the young alive,r although it is believed that the eggsr hatch very shortly after being laid.r

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r The horned lizards or hornedr toads are probably best known forr their peculiar habit of “squirtingr blood from their eyes,” and the Californiar horned lizard seems to ber one of the best performers in thisr respect. Many people have lookedr in vain for the place where a hornr had supposedly punctured the skinr and drawn blood on the hand of ar person holding a specimen. Littler did they realize that the tiny dropsr of blood had been forcibly ejectedr from the delicate eye membranes ofr the horned lizard, perhaps becauser it was very much irritated or unusuallyr angry.r

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r ALLIGATOR LIZARDSr
r Gerrhonotus (See key for species)r

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r The two species of alligator lizardsr found in Yosemite Nationalr Park are very similar in general appearancer and are therefore not consideredr separately in this bulletin.r The alligator lizards are the largestr lizards in the Yosemite region. Theyr sometimes reach a length of twelver inches. Although some whip-tail lizardsr may also measure up to twelver inches, they are much more slenderr and with a shorter body and longerr tail than the alligator lizards.r

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r The common name alligator lizardr is quite applicable for these lizardsr surely resemble a small alligator,r not only in their general appearance,r but in their actions as well.r When fully grown the head is larger and wider than the body and givesr them a look of ferocity. The scalesr are relatively heavy and thick for ar lizard of this size, and the lengthwiser series are very distinct. Becauser of their short and rather weaklyr developed legs and feet, theyr move somewhat awkwardly andr with a wriggle or crawl that hasr caused them to receive the commonr name of snake lizard.r

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r They live up to their ferocious appearancer by being rather irritable,r and they will charge and strike atr almost any object that is moved intor a position before them. They have ar series of sharp pointed teeth, butr they are so short that they will seldomr draw blood unless the lizardsr are aroused to the extreme by handlingr or abuse.r

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r These lizards seem to be most activer in the late afternoon or evening,r at which time they come from theirr shady retreats or shelters underr brush or low growing trees andr shrubs to forage largely on insects.r They do not venture far into the openr but keep within “a dash or two” ofr cover or protection. They usually remainr on the ground, but in denser thickets or fallen underbrush theyr have been observed climbingr through the twigs apparently inr search of insect or other food.r

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r The alligator lizards have a longr slender tail which is easily “parted”r r r r when attacked by their enemies;r however, the power of regenerationr soon produces a tail nearly as longr as the first one, but the new partr seems to be poorly supplied withr nerve fibers and not capable of ther spasmodic jerks for attracting an enemyr like the original caudal appendage.r

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r A few differences between ther two species are perhaps worth mentioning.r The two species seem to occupyr different altitudinal ranges inr the Park with the San Diego alligatorr lizard being found in the Yosemiter Valley and below, while the Sierrar alligator lizard ranges from ther Valley up to elevations as high asr Washburn or Merced Lakes, andr even to 10,000 feet on the west ridger of Red Peak. If live specimens arer available for observation, the twor species are easily distinguishedr by eye color, for in the San Diegor alligator lizard the iris of the eye isr yellow and without dark pigment,r while the eye of the Sierra alligatorr lizard is dark and appears nearlyr black. A further difference is the factr that the San Diego alligator lizardr deposits eggs, while the Sierra alligatorr lizard produces the youngr alive. This seems to be the naturalr specialization of those forms rangingr into the higher and colder elevationsr where damp and cold habitatsr would greatly hinder or prevent ther hatching of eggs.r

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r The alligator lizards belong to ther interesting family known as the Anguidae.r They are poorly representedr in North America. Some of theirr closest relatives are the stranger glass-snake or joint-snake of ther eastern portion of North America,r and the small limbless, burrowingr lizard of the Pacific Coast region.r

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r CALIFORNIA WHIP-TAILED LIZARDr
r Cnemidophorus tessellatus tessellatusr

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r The whip-tailed lizard is foundr only in the extreme western portionr of Yosemite National Park and barelyr reaches the lower end of Yosemiter Valley. These lizards are ordinarilyr considered most at home in ther arid and more desert types of country;r however, a few individuals occupyr the foothill regions and lowerr valleys. Typical habitats are notr present in Yosemite National Park,r but a few specimens have been takenr from the more open, sandy andr warmer sections along the westernr boundary.r

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r The whip-tailed lizard is the swiftestr of all the lizards in this region.r Because of its specialization in slenderr body form, long slender tail, andr modified leg and foot—such modificationsr all assisting in the attainmentr of speed—it is well known andr readily recognized by all those whor are the least interested in naturalr history. Its habit of lifting its tail offr the ground and actually using it asr a rudder or counter-balance whenr running rapidly is an especially interestingr adaptation. When theser lizards are seeking food they mover cautiously but somewhat “jerkily,”r and at that time they drag their longr slender tails, so that they leave anr interesting but characteristic “trailr pattern” when moving over fine dryr sandy soil.r

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r The head and snout is long andr slender. They have a habit of “poking”r the sharp pointed snout intor holes or crevices and at the samer time darting out their delicater tongue. The body measures onlyr three to four inches, but the tailr reaches a length of from seven tor ten inches, thus giving them an overallr length of from ten to fourteenr inches.r

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r The whip-tail lizard feeds largelyr on insects such as grasshoppers,r ground beetles, spiders, ants, larvaer and so forth, and they seldom if everr leave the ground to crawl into brushr or trees or even up and over ther larger boulders. They most certainlyr are typical ground dwellers.r They are abundant and widely distributedr over most of the plains,r prairie and sandy desert country ofr North America, and they exhibitr such great variations in marking andr scale characteristics that they arer one of the most perplexing divisionsr of the lizard group in this country.r

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r They are easily distinguishedr from all other lizards in Yosemiter National Park by the fact that theyr have eight lengthwise rows of fairlyr large, rhomboid-shaped belly scales,r while all other of our lizards haver numerous rows of relatively smallr belly scales.r

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r YOSEMITE SKINKr
r Eumeces gilberti gilbertir

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r Because of its change in colorr pattern from young to adult, and becauser of the irridescent play of colorr often observed on the smooth andr shiny scales, this lizard is one of ther most interesting in Yosemite Nationalr Park. Its habits are such, however,r that very few people ever haver the opportunity to see these lizardsr except in cages or preserved collections.r These lizards, commonlyr called “skinks,” seldom venture farr from shelter. They seem to remainr under cover most of the day butr come out into the open to forage forr food in the late afternoon or evening.r Their food is composed largely ofr r r

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r r YOSEMITE SKINKr
r [click to enlarge]
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r N. P. S. Photo by Andersonr
r YOSEMITE SKINKr
r r r r r insects which they locate on ther ground among piles of dead leavesr and down brush, or amongst ther rubbish accumulated in the cracksr between large boulders.r

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r For a shelter they usually seekr out thin flat rocks on fairly openr hillsides, and several specimensr may sometimes be located under ar single slab of shale. They also taker advantage of fallen logs, and mayr be found under the rotting logs, orr even between the loosened barkr and the log itself.r

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r It is believed that these lizards depositr only a small number of eggs,r and there is some indication that ther females may curl up around ther eggs and thereby assist in their incubation.r

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r The skinks seem to be well adaptedr for quiet movement through fallenr leaves or underbrush. The headr is long and slender and merges intor the body without any noticeabler change. The body continues evenlyr and the tail tapers gradually. Ther legs are short and closely set. Ther scales are very smooth and glossy,r and sometimes in bright sunlight,r show an interesting display of irridescentr coloring. Their entire makeupr enables them to glide and wriggler their way through leaves andr debris with ease and with hardly ar perceptible rustle.r

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r The young are marked so differentlyr from the adults that in the pastr some difficulty was encountered inr recognizing the different species.r The young or immature Yosemiter r skink is dark brown to nearly black,r but with four sharply defined lightr lines or stripes along the back. Ther belly side is pale blue to whitish butr the tail is often brilliant blue, thisr latter characteristic often attractingr immediate attention. As these skinksr mature, usually during the secondr or third year, they gradually changer color. The head becomes reddish tor copper in color; the body turnsr brown to olive-green; they lose theirr stripes entirely, and the tail becomesr somewhat greenish. These colors,r unfortunately, often change or fader considerably in museum specimensr kept in strong preservatives.r

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r Although Eumeces gilberti wasr first recognized and described byr Van Denburgh in 1896, and was ther first species of vertebrate to have ”r Yosemite National Park designatedr as its type locality, it was lost in ther synonomy of Eumeces skiitonianusr until brought out again by Taylor inr 1936.r

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r Skinks in our Museum collectionr have been taken in or near the followingr locations: Tenaya Canyon,r Yosemite Valley, Mirror Lake, Bridalveilr Fall, Mather Ranger Station,r Arch Rock Ranger Station, foot ofr El Capitan, near Swamp Lake, Miguelr Meadows, and near the Governmentr Center. In the summers ofr 1944 and 1945 both adults andr young were observed on several occasionsr emerging from behind ther large Sequoia section just to ther right of the Museum door.r

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r r Next: Snakesr •r Contentsr •r Previous: Turtlesr r

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r http://www.yosemite.ca.us/library/reptiles/lizards.htmlr

r r r r r r r r r r r r r r r r r r Reptiles and Amphibians of Yosemite National Park (1946), “Snakes,” by Myrl V. Walkerr r r r

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r r Next: Simplified Keyr •r Contentsr •r Previous: Lizardsr r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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SNAKES

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r The snakes constitute one of the most perplexing divisions of our entirer group of backboned animals. Their abundance or scarcity and their remarkabler modifications such as loss of legs and specialized heart and lungs,r jaws and teeth, tongue and ears—or rather lack of ears—all contribute tor the problems that have ever challenged the serious student of herpetology.r

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r While a few snakes of some species are to be found in almost any locality,r their abundance or scarcity soon becomes evident to even the experiencedr snake collector. He soon finds that snakes are abundant in a givenr locality, not just one species but often many species, while nearby areasr are relatively barren. The most logical conclusion is that certain areas haver the necessary requirements of food and shelter more favorably developedr than others and therefore the snakes congregate there. The denning habitr of some hibernating snakes also brings together large numbers each springr and fall when these species are either leaving or returning to the dens.r

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r Perhaps it is the apparent scarcity of snakes that intrigues the averager person, for there are many who know little of snake habits. Several of ourr snakes are active only at night, that is, are nocturnal and do their huntingr in the dark. They spend the daylight hours hidden under flat rocks, underr logs, or in crevices in the rocks. Even the species that prowl in the daytimer seek the shelter and protection of flat rocks or fallen logs.r

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r The snake collector does not “beat the brush” seeking to drive out itsr reptilian inhabitants, but rather he goes about his work by slowly turningr over or looking under all of the flat rocks which might provide a hiding placer for the snakes. He is often rewarded by finding several snakes under ar single flat rock—a flat rock that could be resting within a few feet of ar highway or well traveled trail; yet many people might have passed withoutr ever realizing that several snakes could be so close at hand.r

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r Many centuries ago when snakes gave up their legs to crawl on ther ground or into places unavailable to an animal with limbs, they were forcedr to make numerous adjustments not only in their skeletal structure, but inr their internal organs as well. Slenderness and length became necessary inr order to progress in the manner now used by snakes, and all are awarer that the fastest snakes are the longest and most slender, the stubby andr heavy snakes are the slowest. In order to attain this slenderness of bodyr the snakes had to make adjustments in many of their internal organs. Manyr snakes sacrificed one lung entirely and now have but a single lung, andr even that is drawn out into an extremely long and slender organ. The heartr of a snake is also very long and slender and unlike the heart of other vertebrates.r The liver and gall bladder also show a special adaptation to ther space available.r

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r The snakes were forced to swallow their prey entire since they worer without legs or loot to hold it down to tear it apart. This resulted in the developmentr r r r of a peculiarly loosely connected jaw which makes it possibler for the snake to swallow entire objects of considerable size. This in turnr required the aid of powerful digestive juices that soon came into being.r This made it possible for the snake to break down and absorb this quicklyr secured meal in a more protected spot, and in a leisurely manner.r

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r Because a few species of snakes developed poison glands as an aid orr means of quickly subduing their prey and securing their food, and sincer this poison to a greater or lesser degree affects man, these are classed asr dangerous snakes. Unfortunately this has caused a general fear of allr snakes. We respect and perhaps fear the wasps and bees because theyr have stingers and a mild type of poison, but we do not condemn all ther insects such as moths and butterflies just because of the bees and wasps.r This same line of reasoning should be applicable to the snakes as well, andr since we tolerate bees for the honey they produce and the aid they give inr fertilizing certain flowers, we should also tolerate the snakes for their aidr in controlling the ever present rodents.r

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r Most herpetologists now agree that probably no rattlesnake ever heardr itself rattle, for snakes are without external ears. Noise and sound seem tor affect snakes very little, but they are very sensitive to vibrations—a mostr natural specialization since they crawl on the ground. They seem continuallyr to dart out their tongue for it serves to transmit certain materials to a veryr delicate and highly specialized sense organ. This may aid them in tasting orr smelling their way along. The tongue is not an organ of hearing, strictlyr speaking, nor is it a “stinger” as many people have been led to believe.r

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r A number of the snakes deposit eggs under rocks or logs and then mover on, leaving the eggs to hatch and the young to take care of themselves asr best they can. Some of the snakes produce their young alive. The commonr garter snakes often have litters numbering up to thirty-five or forty. Allr snakes shed their skin periodically, not just once a year, but usually severalr times a year, and in the case of the rattlesnakes, they get a new rattle everyr time they shed their skin. It is therefore evident that the number of rattlesr is not a clue to the age of the rattlesnake, but simply an indication of ther number of times it has shed its skin. The more mature rattlesnakes oftenr break off some of the end rattles as they crawl through the rocks and brush,r so after the first two or three years the number of rattles means absolutelyr nothing insofar as age is concerned.r

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r Thirteen snakes have been thus far recorded for Yosemite National Parkr and two of these are very rare and known from only a few specimens. Ther garter snakes are probably the most common, racers and gopher snakesr are moderately abundant, while the beautifully colored and banded kingr snakes, seen by many visitors, are regarded as the most attractive.r

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r PACIFIC RUBBER SNAKEr
r Charing bottae bottaer

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r The rubber snake or rubber boa,r which seldom exceeds twenty tor twenty-four inches in length, mostr certainly exhibits few apparent characteristics,r either of size or temperament,r that would indicate to the casualr observer that it is related to ther large boas of South America. It hasr often been called the “two-headed”r snake because of its very stubbyr tail, and it is difficult at first glancer to tell “which end is which.” Somer observers have been led to believer that the rubber boa takes advantager of this stubby tail, for in the presencer of danger or enemies, while itr keeps its head low and motionless,r it may raise its tail and slowly mover it back and forth thereby simulatingr head movement.r

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r A pair of short spurs or spinesr which project slightly on either sider of the vent appear to represent rudimentaryr legs or portions of ther vestigial pelvic arch. This is one ofr the few snakes that retain evidencer that they once possessed legs.r

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r The rubber boa seems to be wellr adapted to burrowing in damp andr moist soils. Even the bones of ther skull are modified, strongly and solidlyr joined, as are other burrowingr forms. The scales are small and veryr smooth, and the skin seems to ber very loose fitting, thereby giving ther rubber snake an unusual appearancer which makes them readilyr recognized. Those snakes are uniformlyr colonel a dull yellowish tor greenish brown above and a yellowishr r white below, and get their commonr name from their “rubber-like”r color and texture. They are sluggishr and slow moving and seldom if everr make an attempt to protect themselves.r They may be handled easilyr for they seem never to bite or evenr try to bite, and they make little effortr to pull away. They will on some occasions,r however, coil and twist intor a rather tight ball, perhaps as a defensiver measure. Because of this actionr they have sometimes been calledr the “ball snake.”r

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r Although the rubber snake hasr one peculiarity often associated withr the poisonous snakes, that is, the pupilr of the eye is arranged vertically,r it is absolutely harmless and shouldr never be killed just because it is ar snake. We know practically nothingr of its life history and breeding habits,r so anyone that would maker careful observations of this speciesr would be contributing something tor science.r

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r The Pacific rubber snake was oncer considered rather rare in Yosemiter National Park, but recent observationsr seem to indicate that it is atr least fairly wide spread even if notr abundant. Perhaps its very secretiver habits has led to the belief that it is.r rare. Specimens in the Museum collectionr have come from Yosemiter Valley, Yosemite Research Reserve,r Benson Lake, Tuolumne Canyon,r Wawona, and live specimens werer observed during the summer of 1944r near Yosemite Point and betweenr Merced and Washburn Lakes.r

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r r Upper: PACIFIC RUBBER SNAKE  Lower: CORAL-BELLIED RED-NECKED SNAKE r
r [click to enlarge]
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r From Van Denburgh: The Reptiles of Western North America. Courtesy of the
California Academy of Sciences
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r Upper: PACIFIC RUBBER SNAKE
Lower: CORAL-BELLIED RED-NECKED SNAKEr
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r CORAL-BELLIED RING-NECKEDr SNAKEr
r Diadophis amabilis pulchellusr

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r The coral-bellied ring-neckedr snake can be identified with littler difficulty, for it is the only snaker found in Yosemite National Park thatr has the single light colored ringr around the neck. The ventral surfacer is orange to reddish, while ther dorsal surface is uniformly dull colored.r

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r The ring-necked snake is one ofr the smallest snakes found in this region,r and many adult specimens arer no larger than a lead pencil. Theyr seldom reach a length of more thanr fifteen to twenty inches. They arer harmless, will seldom attempt tor bite, and are usually easily handled.r The scales are smooth and relativelyr small. The yellowish or oranger neck ring stands out distinctlyr against the dorsal body color whichr is a uniform olive to bluish or gray.r The color and markings of the bellyr are in sharp contrast to the dorsalr coloration, for the underside is anr orange red, and the tail is even morer brilliantly colored. Because of ther red coloration of the underside, theser snakes are sometimes called “red-bellied”r snakes.r

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r Ring-necked snakes are secretiver in habit and are seldom observed inr the open. They are often found neatlyr coiled under flat rocks, old boards,r or logs. When suddenly uncoveredr they may perform most interestingly,r for occasionally they will turnr belly side up, showing the brilliantr under-markings, and then feignr death, or perhaps more often theyr r will coil the tail into a tight spring-liker spiral that exposes the brightr red coloring of the under-surface. Itr has been assumed by some that thisr may serve either a protective orr warning function.r

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r Recent observations seem to indicater that the ring-necked snakes feedr on small tree toads, occasionally onr some of the smaller snakes, and onr the small or immature lizards of ther skink group. It is believed that theser snakes lay eggs, but not a great dealr is known of the breeding habits ofr this particular species of snake.r

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r The ring-necked snakes are by nor means abundant in Yosemite Nationalr Park; however, our Museumr records show that they are widelyr distributed. Specimens have beenr taken at Bridalveil Fall, Arch Rockr Ranger Station, Swamp Lake Researchr Reserve, Poison Meadow,r above Mirror Lake, and on the trailr below Vernal Fall. Perhaps carefulr collecting will prove their scarcity orr abundance, and will reveal muchr that is not now known of their lifer history and breeding habits.r

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r PACIFIC RATTLESNAKEr
r Crotalus viridus oreganusr

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r Rattlesnakes are present in Yosemiter National Park, but whetherr or not we should say they are abundant,r common, or scarce, dependsr on whether we want to exaggerater or minimize their presence. We dor not have a large series in our Museumr collection; and in view of ther fact that the rattlesnake is easilyr recognized by all, is often killed atr once and is later either brought in orr reported, it would seem that we darer r r r r

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r r Upper: PACIFIC RATTLESNAKE  Lower: PACIFIC GOPHER SNAKE r
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r From Van Denburgh: The Reptiles of Western North America. Courtesy of the
California Academy of Sciences
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r Upper: PACIFIC RATTLESNAKE
Lower: PACIFIC GOPHER SNAKEr
r r r r r go no farther than to say that theyr are common in particularly suitabler habitats. The annual average numberr of reports of observations by hikers,r visitors, road and trail workersr is unexpectedly small; however, ther experienced snake collector mayr have surprisingly good success if her locates an especially productiver area.r

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r It is perhaps unnecessary to giver much of a description of the rattlesnake,r for it is usually recognized atr a glance because of the triangularr shape of the head, the thick, shortr body, and the presence of the tailr rattle. The Pacific rattlesnake, ther only species of rattlesnake found inr Yosemite National Park, probablyr does not exceed a length of fromr three to four feet, but some specimensr are unusually robust in body size.r They seem to frequent the rockyr talus slopes of canyons and valleys,r but may also be encountered inr more open country or dry grassyr meadows.r

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r Rattlesnakes appear to be widelyr distributed in the Park and somer specimens have been taken at elevationsr that would seem above ther normal range of such snakes. Specimensr in our collection have beenr taken in Tenaya Canyon — 6500r feet; Yosemite Valley — 4000 feet;r Wawona — 4100 feet; Big Meadowsr —4400 feet; Hetch Hetchy Valley—r 4200 feet; East base of Half Dome—r 7800 feet; base of El Capitan—4010r feet; Gentry Ranger Station—5500r feet; and at Miguel Meadows—5200r feet.r

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r The rattlesnake seems to feed onr r a number of rodents including ther various species of ground squirrelsr and chipmunks, and it appears thatr their venom is perhaps particularlyr effective on these small warm-bloodedr vertebrates. The rattlesnakes dor not lay eggs, but produce their youngr alive; however, broods are usuallyr small and number not more thanr about a dozen.r

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r There are so many fallacies andr folk tales associated with the rattlesnakesr that one is hesitant even tor enumerate them, but perhaps a fewr will suffice to cover the salient topicsr and will thereby encourage thoser who are interested to do some readingr on the subject. A number of theser can be briefly contradicted by ther following negative facts: — rattlesnakesr (1) do not chase people, (2)r do not cover a greater distance thanr their length when striking, (3) canr not hear themselves rattle, (4), dor not use their poison primarily tor frighten people, (5) do not have ar rattle for each year of their life, (6)r are not always deadly poisonous,r (7) can not be made harmless for anyr length of time by pulling out theirr fangs, and (8) do not always rattler before they strike. On the other handr the following positive facts are verifiable:—rattlesnakesr (1) will die fromr their own bite, (2) will congregate inr large numbers in the winter time inr snake dens, (3) will often strike withoutr inserting their fangs, (4) will soonr grow new fangs to replace thoser broken off naturally or pulled out byr man, (5) will shed their skin severalr times a year, (6) will add another rattler teach time they shed, (7) will “gor r r r blind” not just once a year but eachr time they shed their skin, and (8)r will, as adults, normally inject morer poison than the young.r

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r Everyone is of course interested inr the proper treatment for rattlesnaker bite. It should be emphasized, however,r that “an ounce of prevention isr worth a pound of cure.” Hikers willr seldom encounter rattlesnakes on ther well-traveled trails, but when theyr leave the trails for exploring on theirr own they should take certain precautionsr such as wearing properr shoes, boots or leggings. They shouldr also avoid stepping or placing theirr hands near cracks or joints in ther rocks which might serve as retreatsr for the rattlesnakes.r

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r Hikers or campers who make ar practice of leaving the well-traveledr routes should provide themselvesr with the latest type first-aid kits andr should have some training or experiencer in the proper use of theser safety-first aids. Practically all of ther modern first-aid kits contain very definiter instructions as to their properr use, and these instructions should ber carefully studied by those who travelr away from the regular trails in rattlesnake-infestedr country.r

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r PACIFIC GOPHER SNAKEr
r Pituophis catenifer cateniferr

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r The Pacific gopher snake, oftentimesr called “bull snake,” is notr widely distributed in Yosemite Nationalr Park but seems confined tor the lower elevations. It is not primarilyr a snake of the forested andr rocky areas but rather of the openr grasslands, sandy foothills, and valleys.r r It takes full advantage of ther burrows of gophers, mice and groundr squirrels, with many of the originalr inhabitants of the burrows beingr taken for food.r

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r The gopher snake is probably givenr more consideration and affordedr more respect than any other of ourr common snakes. Great emphasisr has long been placed on its economicr value because of the larger number of gophers and other rodentsr that it destroys, and it is toleratedr and sometimes even encouraged byr the farmer and ranchman.r

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r These snakes are often rather inactive,r especially the adults, and appearr somewhat slow and sluggish.r When first surprised they will oftenr lie motionless, but if approached andr molested they will coil and strike repeatedly,r and will at the same timer puff themselves up by taking in airr which they expel rapidly and therebyr make a strange fluttering andr hissing noise. In addition many gopherr snakes have been observed tor vibrate the tail rapidly, and if theyr happen to be in a pile of dead or dryr leaves, the result is usually a rustler or “rattle” sounding very much liker a rattlesnake. This entire performancer is usually all bluff, for if ar person continues to advance and eitherr places his foot on the snake orr holds it down with a stick, it willr often become rather docile in just ar few minutes and can even be pickedr up and handled with ease. Theser snakes are well supplied with shortr but strong, sharp recurved teeth andr they make a nasty wound if allowedr to bite. Although they are not poisonousr r r r they should be handledr carefully and never given an opportunityr to bite, for such wounds mayr very easily become infected.r

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r The adult gopher snakes arer probably the largest snakes foundr in this region, for they are ratherr bulky in addition to the fact that theyr sometimes reach a length of threer to four feet. The tail is long and tapersr to a point. This is very differentr from the rattlesnake which has ar short blunt tail. The gopher snakesr all have a peculiarly enlarged scaler (rostral) on the tip of the snout thatr is extended upward and backward,r apparently an adaptation for burrowing.r This will distinguish themr from all other snakes in Yosemiter National Park. The general bodyr color of gopher snakes is a darkr ocher yellow but they are markedr on the back with a series of darkr brown saddle marks or blotches andr with small dark spots along ther sides. The pattern of marks on ther back is often mistakenly assumed tor be “diamond” shaped and at firstr glance are sometimes confused withr the markings of the rattlesnake.r

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r The gopher snakes deposit ar small number of eggs which arer placed either under rocks, in shallowr burrows which they themselvesr make, or in burrows of gophers orr ground squirrels.r

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r The Pacific gopher snake has beenr taken in Yosemite National Park inr Yosemite Valley, at Arch Rockr Ranger Station, Miguel Meadows,r and near the hose of El Capitan.r

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r WHIPSNAKES AND RACERSr
r Coluber (See key for species)r

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r The western blue racer and ther California striped whipsnake arer quite unlike in general appearance,r but since they belong to the samer genus they are not treated separately.r They are typical of our racersr and whipsnakes, being very longr and slender and capable of movingr rapidly. They are adapted not onlyr for speed on the ground, but theyr seem to climb readily in shrubs andr trees. Their food supply is extremelyr varied for they take insects, toads,r frogs, lizards, small mammals,r young birds in the nests, and evenr bird eggs. Contrary to popular belief,r they do not kill by constrictionr or “squeezing” their prey.r

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r In Yosemite National Park ther adult western blue racer may ber readily distinguished from the adultr California striped whipsnake becauser the former is uniformly coloredr a bluish brown, and withoutr any indication of lateral or dorsalr striping, while the latter is dark brownr and with two very distinct lateralr light lines that extend the full lengthr of the body. The young of the westernr blue racer display a color patternr very unlike the adult. They arer blotched, spotted and barred, andr are often confused with young gopherr snakes or night snakes by ther casual observer. The striped whipsnaker may be distinguished fromr the other commonly striped snakesr (garter snakes) because the latterr nearly always possesses a mid-dorsalr light line in addition to the lateralr r r r r

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r r Upper: WESTERN BLUE RACER  Lower: CALIFORNIA STRIPED WHIPSNAKE r
r [click to enlarge]
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r From Van Denburgh: The Reptiles of Western North America. Courtesy of the
California Academy of Sciences
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r Upper: WESTERN BLUE RACER
Lower: CALIFORNIA STRIPED WHIPSNAKEr
r r r r r light lines, and furthermore, ther racers and whipsnakes have smoothr scales while the garter snakes haver a ridge or keel down the center ofr lateral and dorsal scales.r

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r The western blue racer is oftenr called the yellow-bellied racer becauser the underside of the body isr plain yellow. They reach a length ofr slightly over four feet. They depositr fairly large numbers of eggs thatr hatch in two to three months.r

r r

r Because of their habit of movingr with the head often lifted some distancer off the ground, they have nor doubt been responsible for suchr snake fallacies as the hoop snaker story and the idea that these snakesr chase people. Perhaps the snakesr that “chased” people were just overlyr inquisitive and let their curiosityr cause them to move forward,r perhaps toward or more often afterr the observer, with their heads wellr raised off the ground. Their curiosityr satisfied, they will usually “turn tailr and run.”r

r r

r The California striped whipsnaker has a very long tail that tapers to ar point, and the scalation so resemblesr the old fashioned braided whipr that the common name has been applied.r This whipsnake seldom exceedsr four and a half feet in length.r Their food is varied but they seemr to catch an unusually large numberr of skinks. On a few occasions theyr have been observed killing and eatingr rattlesnakes.r

r r

r Both the racers and whipsnakesr prefer the more open brushy hillsidesr and dry grassy meadows. Inr Yosemite National Park the westernr r blue racer, which seems to be ther most abundant, has been taken inr Yosemite Valley, El Capitan Meadow,r Pate Valley, and near Swampr Lake. The California striped whipsnaker has been taken in Miguelr Meadows, on Henness Ridge, inr Poison Meadows, and near Cascader Creek.r

r r

r THE GARTER SNAKESr
r Thamnophis (See key for species)r

r r

r Everyone is familiar with the garterr snakes for they are not onlyr widely distributed, but individualsr exist in greater numbers than anyr other group of snakes in North America.r Their striped characteristics arer recognized by all, and since theyr frequent ponds, streams, and lakes,r the hiker, fisherman, and the picnickerr are always aware of their existence.r

r r

r The garter snakes are generallyr accepted as harmless and not ar great deal of heed is given them.r Some forms will bite viciously, however,r and their sharp recurved teethr will produce some bad scratches.r They should be handled carefullyr and never allowed to bite for theirr teeth may carry decayed food orr other infectious materials. Some ofr the garter snakes have the bad habitr of giving off a very ill smelling andr nauseating secretion from specializedr anal glands whenever they arer picked up, and when they whipr their bodies and tails around andr smear this material over themselvesr it most certainly discourages one’sr fondling them. In the wild this mayr afford them some measure of protectionr r from enemies.r

r r r r r r r r r
r r Upper: CALIFORNIA RED-SIZED GARTER SNAKE  Lower: SIERRA NEVADA GARTER SNAKE r
r [click to enlarge]
r
r From Van Denburgh: The Reptiles of Western North America. Courtesy of the
California Academy of Sciences
r
r Upper: CALIFORNIA RED-SIZED GARTER SNAKE
Lower: SIERRA NEVADA GARTER SNAKEr
r r r r r r

r One of the interesting characteristicsr of the garter snakes is the factr that they do not lay eggs, but producer their young alive, and furthermore,r they sometimes produce littersr of considerable size with adultr averages of some species runningr thirty to forty per litter. It is no wonderr then that the garter snakes arer so abundant. These snakes are perhapsr as much responsible as anyr of the snakes for the fallacy thatr snakes swallow their young. Ther story is usually “proven” when ther observer claims to have later killedr the snake and discovered the youngr inside. What he did not realize wasr that he had merely revealed ther presence of a number of unbornr young that were not in the stomach,r but in the oviducts of the female.r

r r

r The three species of garter snakesr found in Yosemite National Parkr show sufficient distinctive characteristicsr and occupy different rangesr and zones so that they may usuallyr be identified without too much difficulty;r however, this does not holdr true for the country as a whole, andr the garter snakes constitute a ratherr difficult group to study.r

r r

r The California red-sided garterr snake may be recognized by ther presence of red spots along eitherr side, in addition to the distinct lateralr and mid-dorsal light lines orr stripes. These snakes are not larger and seldom exceed two feet inr length. They are not abundant in ther Park and are apparently limited tor the lower elevations. They mayr reach the lower end of the Valley,r r but most of our records are from ther vicinity of Swamp Lake and Miguelr Meadows.r

r r

r The mountain garter snake occupiesr a higher range, and is mostr abundant at Tuolumne Meadows,r Benson Lake, Yosemite Researchr Reserve, Lukens Lake, Cold Canyon,r Harden Lake, and Turners Meadow.r This snake possesses three very distinctr light lines, two lateral and oner mid-dorsal, but there are no red sider spots as in the red-sided garterr snake. The mountain garter snaker seldom exceeds two feet in length.r

r r

r The Sierra Nevada garter snaker differs from the two other garterr snakes in that its stripes are less distinct,r and often the dorsal stripe isr broken into a series of spots, or mayr actually be missing. The sides arer barred with alternating dark to blackr spots. Most of the garter snakes arer at home near ponds, lakes, andr streams, however, this garter snaker actually takes to the water and mayr be found in and along swiftly movingr streams. It is approximately ther same length as the two striped garterr snakes, but appears to be a bitr more robust in general body proportions.r The Sierra Nevada garterr snake has been taken along ther Merced River in Yosemite Valley,r near Merced Luke, Pate Valley,r Swamp Lake, and Miguel Meadows.r

r r

r The garter snakes all secure theirr food close to their pond, stream orr lake habitat, and they take a larger number of toads, frogs, salamanders,r and occasionally fish eggs andr small fish.r

r r r r r r r r r
r r Upper: SPOTTED NIGHT SNAKE  Lower: SIERRA CORAL KING SNAKE r
r [click to enlarge]
r
r From Van Denburgh: The Reptiles of Western North America. Courtesy of the
California Academy of Sciences
r
r Upper: SPOTTED NIGHT SNAKE
Lower: SIERRA CORAL KING SNAKEr
r r r r r r

r SPOTTED NIGHT SNAKEr
r Hypsiglena ochrorhyncha ochrorhynchar

r r

r The spotted night snake is anotherr of the small snakes present inr Yosemite National Park. Adults seldomr reach a length greater than fifteenr to twenty inches. They are nor much larger around than a lead pencil.r The general color is a dullish-whiter covered with innumerabler tiny specks of brown to black, butr there are two mid-dorsal rows of alternatingr black spots, often actuallyr touching, and with two or more rowsr of lateral side spots, the lowermostr quite small. The nape of the neck isr crossed with a wide black bandr that extends forward through ther eye. The belly is whitish and spotless.r The pupil in the eye of ther spotted night snake is interesting forr it is arranged vertically like that ofr some poisonous snakes.r

r r

r The size of this snake renders itr relatively harmless to man, althoughr some of the rear teeth are enlarged,r and there is some indicationr that these snakes have a poisonr that is effective on small lizards. Orr one occasion a night snake was observedr to strike a small Sceloporusr lizard, grasping it around the bodyr a short distance back of the frontr legs. The snake quickly coiledr around the lizard and appeared tor exert some constriction. They werer separated in a few minutes, but withr some difficulty. Tho lizard remainedr motionless and seemed completelyr paralized, although it continued tor breathe. It was rolled over and placedr r on its feet but it made no effortr to move. The snake made no attemptr to eat the lizard, and the next morning,r some twelve hours later, ther lizard was dead and in exactly ther same position and location in the jarr as when last observed the night before.r

r r

r The spotted night snake seems tor be extremely rare for specimens arer usually found only when uncoveredr in road building or ditching operations,r or when turning over flatr rocks. One exception, however, wasr a specimen observed by the aid ofr a flash light about 10:00 o’clock atr night. It quickly vanished under ar flat rock, but was pulled out with ther aid of a small wire. When held inr the hand it would attempt to striker and to pull away, and it was especiallyr strong and muscular for sor small a snake. Even after three orr four days in a small jar, duringr which time it was handled on severalr occasions, it still exhibited its viciousr belligerent attitude.r

r r

r The common name “night snake”r is indicative of its habits, for it seemsr to be active only at night. It is, therefore,r doubtful if many people willr ever see specimens of this snake exceptr in museum collections. Not ar great deal is known of its food preferencesr or breeding habits.r

r r

r In Yosemite National Park it hasr been taken from under a flat rockr near the base of El Capitan at an elevationr of 4000 feet, and along ther Big Oak Flat road by members of ar road crew working at an elevationr of 5000 feet.r

r r r r r

r SIERRA CORAL ICING SNAKEr
r Lampropeltis multicincta multicinctar

r r

r Since some people object to callingr a snake beautiful, we shall ber considerate, but on the other handr we must say that the Sierra coralr king snake, often called mountainr king snake, is one of the most attractivelyr and vividly colored snakesr in Yosemite National Park.r

r r

r The series of red, white, and blackr bands that appear to encircle thisr snake, especially in specimens thatr have only recently shed their skin,r never fail to bring forth exclamationsr of surprise and wonder evenr from the most avowed “snake haters.”r It is the only snake in Yosemiter National Park with distinctive red,r white and black color bands; thereforer it is easily recognized by everyone.r It should be pointed out, howeverr that an occasional specimen isr found with the red almost entirelyr absent. This may make it difficult tor distinguish at first glance from ther California king snake. The scales ofr this snake are very smooth, notr keeled as in the garter snakes, andr this perhaps adds to the brilliancyr of the colors, especially in specimensr that have only recently shedr their skin.r

r r

r The Sierra coral king snake seldomr exceeds a length of from twenty-fiver to thirty inches. It seems to inhabitr the rocky talus slopes alongr either side of Yosemite Valley andr specimens in our collection haver come from Mirror Lake, Tenayar Canyon, Cascade Creek and fromr various localities in the Valley itself.r

r r

r These snakes are very quiet andr docile, especially in captivity, andr they may be picked up and handledr with ease, for only rarely will theyr attempt to bite. Their gentlenessr seems to belie the fact that in ther wild they are often predacious andr feed not only on lizards, but on otherr snakes as well, and not even hesitatingr to occasionally destroy a rattlesnake.r Some observers believer the king snakes are immune to ther poison of the rattlesnake.r

r r

r Unfortunately the Sierra coral kingr snake is often confused with the poisonousr coral snake (Micrurus) whichr is never found in this region. This isr due not only to the common name,r but also because of the banded colorr pattern as well. Because of thisr misunderstanding many people killr the Sierra coral king snake wheneverr one is found. It should ber pointed out, however, that they arer not only harmless, but in additionr are of considerable economic valuer because of the large number of rodentsr they destroy. In captivity theyr have been observed feeding onr skinks and small Scelopous lizards.r

r r

r CALIFORNIA KING SNAKEr
r Lampropeltis getulus californiaer

r r

r The California king snake, so conspicuousr because of its pattern ofr black and white rings, is one of ther most interesting of our larger snakes.r It is commonly quite gentle and dociler and does not resent being handled.r It makes one of the most easilyr kept of all reptile “pets” because itr feeds so readily in captivity. It willr r r r usually take mice, gophers or smallr ground squirrels as soon as theirr presence is observed by the snake.r

r r

r This king snake is a very goodr bluffer, however, and will often showr fight when first cornered. It willr strike out in a threatening mannerr and in addition will cause the tailr to vibrate very rapidly. When thisr occurs in a pile of dry leaves orr twigs the result is a faint buzz or rattler which is enough like the soundr made by a rattle-snake to cause oner r to move forward with caution.r

r r r r r r r r
r r CALIFORNIA KING SNAKEr
r [click to enlarge]
r
r N. P. S. Photo by Andersonr
r CALIFORNIA KING SNAKEr
r r r

r The food habits of this king snaker cause it to have more than ordinaryr economic importance. It not only destroysr obnoxious rodents such asr mice, gophers and ground squirrelsr —occasionally it may even destroyr rattlesnakes—but it shows no hesitancyr in destroying some of the otherr r beneficial snakes. Its cannibalisticr habits are well known to all snaker collectors, for many a specimen hasr been “lost in the bag” during fieldr collecting expeditions.r

r r

r This particular species of kingr snake has a most interesting andr variable color-phase in certain areasr in California, the rings sometimesr being replaced by a broad medianr longitudinal stripe, but thus far allr specimens taken in the Yosemite regionr hold true to the black and whiter r ring pattern.r

r r

r The California king snake sometimesr reaches a length of over fortyr inches. A specimen caught in ther Museum wildflower garden in ther summer of 1945 measured 41 1/2r inches in total length. This specimenr seemed to be particularly large andr robust for most specimens observedr r r r only average from 30 to 36 inches inr length, and many are rather slender.r

r r

r The scarcity of specimens in ther Museum collection would tend to indicater that this species is rather rarer within the boundaries of the Park.r Information gathered and observationsr made during the summer ofr 1945 seem to prove such is not ther case, for at least six or eight specimensr were reported that season;r however, all were observed near orr on the floor of Yosemite Valley, sor that the distribution of this speciesr may be somewhat limited.r

r r

r SHARP-TAILED SNAKEr
r Contia tenuisr

r r

r The sharp-tailed snake is ther smallest snake found in Yosemiter National Park. The few specimensr r observed indicate that it is about asr large as a pencil and seldom exceedsr a length of twelve or fourteenr inches. It is considered the rarest ofr all our Yosemite snakes, for wer have only two specimens in ourr study collection, and records of onlyr two others being taken in the Park.r One specimen in our collection wasr picked up along the roadside nearr the Big Trees Lodge in the Mariposar Grove, and the other was found underr an old pile of magazines in ar dark closet of one of the unoccupiedr buildings at Wawona. Another specimenr was found near the Mercedr Grove by workers engaged in Ribesr eradication, but unfortunately thisr specimen was later lost. The fourthr specimen was discovered by workersr in the Ribes eradication camp atr r r

r r r r
r r SHARP-TAILED SNAKEr
r [click to enlarge]
r
r N. P. S. Photo by Andersonr
r SHARP-TAILED SNAKEr
r r r r r Wawona. It was discovered under ar Ribes bush that was being uprooted.r The snake was picked up and handiedr by several of the boys but itr escaped into a hole from which theyr were unable to retrieve it.r

r r

r The sharp-tailed snake is ratherr stout for its length, and the tailr quickly tapers to a sharp point. Ar specimen kept alive and under observationr for nearly two months isr described as follows: The color abover is a pinkish orange grading towardr a pinkish brick red. The dorsal scalesr are all uniformly colored, with onlyr a faint trace of flecking with darkerr shades. A lateral dark line is presentr on either side involving the second,r third and lower half of ther fourth scale rows. The ground colorr of these scales is nearly white, butr they are shaded dark due to ther many fine black to slate flecks orr blotches.r

r r

r The underside is a creamy whiter r but with a transverse black bandr across each belly plate. A darkr stripe runs from each nostril backr through the eye and extends a shortr distance beyond the last labialr scales.r

r r

r The sharp-tailed snake is of especialr interest because the tail terminatesr very abruptly and the scales arer modified into a rather sharp spine,r hence the common name. This snaker is no doubt partly responsible forr the myth about the snake with ar “stinger” in the end of its tail. Therer is some evidence that this sharp-pointedr tail may be used in a defensiver manner. Other observationsr seem to indicate that it may have ar special use in burrowing, for nor doubt these snakes are nocturnalr and burrow-inhabiting forms.r

r r

r Practically nothing is known ofr the breeding or food habits of thisr small snake, nor of its distributionr within the Park.r

r r r

r r Yosemite panorama sketchr

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r FRESNO, CALIFORNIAr
r Union bug: Allied Printing Trades Council Union Label Fresno 5r

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r r r r r r r r r r r r r r r r r r Reptiles and Amphibians of Yosemite National Park (1946), “Simplified Key,” by Myrl V. Walkerr r r r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

r r r r r
r r r r

r A SIMPLIFIED KEY*r
r TO THE REPTILES AND AMPHIBIANS OFr
r YOSEMITE NATIONAL PARKr

r r

r * In an effort to make this key workable for a majority of the Park visitors, it has been mader as simple as possible. Diagnostic characters used are those most easily observed and understood.r They do not follow natural relationships or conform to the technical keys ordinarily used byr zoologists. This key will therefore apply only to the amphibians and reptilesr found inr Yosemite National Park,r and and can not be used to identify species found outside thisr area.r

r r r

r 1a. Vertebrates with body covering smooth. Usually moist. No scales, feathers, hairs, clawsr or nailsr r Amphibiansr r 2r

r r

r 1b. Vertebrates with body covering of dry scales. No feathers or hairr r Reptilesr r 10r

r r

r 2a. Amphibians with an elongate body and a tail which is present, throughout lifer
r r Salamandersr r 3r

r r

r 2b. Amphibians with adult body short. No tail in adultsr r Toads and Frogsr r 5r

r r

r 3a. Salamanders with skin slightly rough—reddish brown above—not spottedr
r r SIERRA NEWT— Triturus sierrae Twittyr r p. 5r

r r

r 3b.r r Salamanders with skin very smooth—more or less spottedr r 4r

r r

r 4a. Body brownish black with a few yellow or orange spotsr
r r SIERRA NEVADA SALAMANDER—Ensatina sierrae Storerr r p. 6r

r r

r 4b. Body chocolate or slate color with numerous grayish spots r
r r MOUNT LYELL SALAMANDER—Hydromantes platycephalus Campr r p. 7r

r r

r 5a. Adults with parotoid glands presentr r Toadsr r 6r

r r

r 5b.r r Adults with parotoid glands absentr r 7r

r r

r 6a. Toads with large parotoid glands. Space between glands wider than one gland r
r r CALIFORNIA TOAD—Bufo boreas halophilus Baird and Girardr r p. 10r

r r

r 6b. Toads with small parotoid glands. Space between glands smaller than one glandr
r r YOSEMITE TOAD—Bufo canorus Campr r p. 10r

r r

r 7a. Toes with expanded adhesive discs at their tips r
r r PACIFIC TREE TOAD—Hyla regilla Baird and Girardr r p. 12r

r r

r 7b. Toes without expanded adhesive discs at their tipsr r Frogsr r 8r

r r

r 8a. Frogs with red coloring on inner side of hind legs r
r r CALIFORNIA RED-LEGGED FROG—Rana aurora draytonii Baird and Girardr r p. 13r

r r

r 8b.r r Frogs with yellow coloring on inner side at hind legsr r 9r

r r

r 9a. Heel of hind leg reaching beyond nostril when leg is bent forwardr
r r CALIFORNIA YELLOW-LEGGED FROG—Rana boylii boylii Bairdr r p. 14r

r r

r 9b. Heel of hind leg not reaching beyond nostril when leg is bent forwardr
r r SIERRA YELLOW-LEGGED FROG—Rana boylii sierra Camp.r r p. 14r

r r

r 10a.r r Reptiles with four legsr r 11r

r r

r 10b.r r Reptiles without legsr r 20r

r r

r 11a. Body covered above and below with a bony shell, commonly called carapace andr plastronr
r r WESTERN POND TURTLE—Clemmys marmorata Baird and Girardr r p. 17r

r r

r 11b. Body covered with large or small scalesr r Lizardsr r 12r

r r

r 12a.r
r r Lizards with a series of femoral pores (a row of glandular pores on underside of ther thigh)r r 13r

r r

r 12b.r r Lizards without femoral poresr r 18r

r r

r 13a. Head adorned with a number of short sharp horns r
r r CALIFORNIA HORNED LIZARD—Phrynosoma blainvillii frontale Van Denburghr r p. 21r

r r

r 13b.r r Head without hornsr r 14r

r r

r 14a. Belly scales large. In eight longitudinal rowsr
r r CALIFORNIA WHIP-TAILED LIZARD—Cnemidophorus tessellatus tessellatus Sayr r p. 24r

r r

r 14b. Belly scales small and numerousr r Sceloporusr r 15r

r r

r 15a. Scales on back of thigh not keeled r r
r MOUNTAIN LIZARD—Sceloporus graciosus graciosus Baird and Girardr
r p. 19r

r r r r

r 15b.r r Scales on back of thigh strongly keeledr r 16r

r r

r 16a. Blue belly patches confluent (fused) with blue throat patches. Not separated by a lighterr bandr
r r TENAYA BLUE-BELLIED LIZARD—Sceloporus occidentalis taylori Campr r p. 19r

r r

r 16b.r r Blue belly patches not confluent but separated from blue throat patchr r 17r

r r

r 17a. Adult males with lateral blue throat patches distinct or slightly fused. (Never fused inr yng.)r
r r WESTERN FENCE LIZARD—Sceloporus occidentalis occidentalis Baird and Girardr r p. 19r

r r

r 17b. Adult males with single central blue throat patch. Never divided r
r r PACIFIC BLUE-BELLIED LIZARD—Sceloporus occidentalis biseriatus Hallowellr r p. 19r

r r

r 18a. Dorsal scales smooth. No raised ridge running lengthwise of scale r
r r YOSEMITE SKINK—Eumeces gilberti gilberti Van Denburghr r p. 25r

r r

r 18b. Dorsal scales keeledr r Gerrhonotusr r 19r

r r

r 19a. Dorsal scale rows usually 14. Iris of eye yellow (live specimens) r
r r SAN DIEGO ALLIGATOR LIZARD—Gerrhonotus multi-carinatus webbii Bairdr r p. 23r

r r

r 19b. Dorsal scale rows usually 16. Iris of eye dark (live specimens) r
r r SIERRA ALLIGATOR LIZARD—Gerrhonotus coeruleus palmeri Stejnegerr r p. 23r

r r

r 20a.r r Snakes with pupil of eye verticalr r 21r

r r

r 20b.r r Snakes with pupil of eye roundr r 23r

r r

r 21a. Dorsal body scales strongly keeled. Tail with rattle r
r r PACIFIC RATTLESNAKE—Crotalus viridus oreganusr r Holbrook p. 31r

r r

r 21b.r r Dorsal body scales smoothr r 22r

r r

r 22a. Tail short and stubby. Skin loosely fittingr
r r PACIFIC RUBBER SNAKE—Charina bottae bottae Blainviller r p. 29r

r r

r 22b. Tail not short or stubby. Skin normal r
r r SPOTTED NIGHT SNAKE—Hypsiglena ochrorhyncha ochrorhyncha Coper r p. 41r

r r

r 23a.r r Dorsal body scales keeledr r 24r

r r

r 23b.r r Dorsal body scales smooth. Not keeledr r 27r

r r

r 24a. Body scales in 29 or more rows r
r r PACIFIC GOPHER SNAKE—Pituophis catenifer catenifer Blainviller r p. 34r

r r

r 24b. Body scales in 19 to 21 rowsr r Garter Snakesr r 25r

r r

r 25a. Garter snakes without conspicuous lateral or dorsal light linesr
r r SIERRA NEVADA GARTER SNAKE—Thamnophis ordinoides couchii Kennicottr r p. 37r

r r

r 25b.r r Garter snakes with conspicuous lateral and dorsal light linesr r 26r

r r

r 26a. With reddish spots or bars on sides r
r r CALIFORNIA RED-SIDED GARTER SNAKE—Thamnophis sirtalis tetrataenia Yarrowr r p. 37r

r r

r 26b. Without reddish spots or bars on sides r
r r MOUNTAIN GARTER SNAKE—Thamnophis ordinoides elegans Baird and Girardr r p. 37r

r r

r 27a. Tail short. Ending in a sharp point or spine r
r r SHARP-TAILED SNAKE—Contia tenius Baird and Girardr r p. 44r

r r

r 27b.r r Tail not short. Normally long and slenderr r 28r

r r

r 28a.r r Anal plate dividedr r 29r

r r

r 28b.r r Anal plate single. Not dividedr r 31r

r r

r 29a. A single light neck ring or nuchal collar present r
r r CORAL-BELLIED RINGNECK—Diadophis amabilis pulchellus Baird and Girardr r p. 31r

r r

r 29b.r r Neck ring not presentr r 30r

r r

r 30a. Body with conspicuous lateral light lines r
r r CALIFORNIA STRIPED WHIPSNAKE—Coluber lateralis Hallowellr r p. 35r

r r

r 30b. Body with lateral light lines. Belly yellowr
r r WESTERN BLUE RACER—Coluber constrictor mormon Baird and Girardr r p. 35r

r r

r 31a. Body marked with rings or cross bands of black and white only r
r r CALIFORNIA KING SNAKE—Lampropeltis getulus california Blainviller r p. 42r

r r

r 31b. Body marked with rings or cross bands of black, white and red r
r r SIERRA CORAL KING SNAKE—Lampropeltis multicincta multicincta Yarrowr r p. 42r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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r r r

SELECTED REFERENCES*

r r r

r Bishop, S. C., Handbook of the Salamanders of North America. The Comstock Publishing Co.r Ithaca, New York. 1943.r

r r

r Burt, Charles E., Teiid Lizards of the Genus Cnemidophorus. United States National Museumr Bulletin No. 154. Washington, D. C. 1931.r

r r

r Ditmars, Raymond L., The Reptiles of North America. Doubleday, Doran and Company, Inc.r New York City, New York. 1940.r

r r

r Fitch, Henry S., A Biogeographic Study of the Ordinoides Artenkreis of Garter Snakes. (Genusr Thamnophis) University of California Publications in Zoology, Vol. 44, No. 1. University ofr California Press. Berkeley and Los Angeles, California. 1940.r

r r

r Fitch, Henry S., A Systematic Account of the Alligator Lizards (Gerrhonotus) in the Westernr United States and Lower California. The American Midland Naturalist, Vol. 20, No. 2. Ther University Press, Notre Dame, Indiana. 1938.r

r r

r Grinnell, Joseph, and Tracy I. Storer, Animal Life in the Yosemite. University of Californiar Press. Berkeley, California. 1924.r

r r

r Klauber, Laurence M., A Statistical Study of the Rattlesnakes and numerous related papers onr reptiles. Occasional Papers and Transactions, San Diego Society of Natural History. Sanr Diego, California. 1936-1943.r

r r

r Schmidt, Karl P., and D. Dwight Davis, Field Book of Snakes of the United States and Canada.r G. P. Putnam’s Sons. New York City, N. Y. 1941.r

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r Slevin, Joseph R., The Amphibians of Western North America. Occasional papers of the Californiar Academy of Sciences, No. 16. Published by the Academy. San Francisco, California.r 1928.r

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r Smith, Hobart M., Handbook of the Lizards of North America. The Comstock Publishing Co.r Ithaca, New York. (In press)r

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r Stejneger, L., and T. Barbour, A Check List of North American Amphibians and Reptiles. Harvardr University Press. Cambridge, Mass. 1939.r

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r Storer, Tracy I., A Synopsis of the Amphibia of California. University of California Publicationsr in Zoology, Vol. 27. University of California Press. Berkeley, California. 1925.r

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r Taylor, Edward H., A Taxonomic Study of the Cosmopolitan Scincoid Lizards of the Genusr Eumeces. The Kansas University Science Bulletin, Vol 28. Published by the University.r Lawrence, Kansas. 1935.r

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r Van Denburgh, John, The Reptiles of Western North America. Occasional Papers Californiar Academy of Sciences, No. 10, Vol. 2, San Francisco, California, 1922.r

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r Wright, Albert Hazen, and Anna Allen Wright, Handbook of Frogs and Toads. The Comstockr Publishing Co., Ithaca, New York. 1942.r

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r *In order to keep the number of references to a minimum the above list contains only a fewr outstanding publications in each field. From these may be secured innumerable additionalr references or citations to other publications. Many of these standard works have extensiver bibliographies.r

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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Reptiles and Amphibians of Yosemite National Park (1946) by Myrl V. Walker

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About the Author

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r r Myrl V. Walker, 1931r
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r Myrl V. Walker, 1931r
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r Myrl V. Walker was born March 20, 1903.r He married Wilda O. Walker in the 1920s.r He also began collecting fossils in the 1920sr as a student of Dr. George F. Sternberg,r an early Kansas fossil collector,r and later studied under Dr. L. D. Wooster, a paleonthologist.r Walker began teaching Junior High at Protection, Kansas, while attending Fort Hays State College during summer and later full time.r He received his bachelor’s degree in 1927.r After graduating, Walker taught high school at Plainville, then at the biology department at Kansas State Teachers College in 1929 (now Fort Hays State University).r In 1930 he was high school principal, coach, and science instructor.r He received his master’s degree in vertebrate paleonthology from the University of Kansas in 1931.r

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r Walker became a seasonal ranger naturalist in 1933.r In 1944 he was appointed asr Associate Park Naturalist in Yosemite National Park.r He transferred in 1933 to Petrified Forest National Monument, then to Zion National Park, Crater Lake National Park, and Glacier National Park, and back to Yosemite in 1944.r In 1951 he was head of interpretation at Zion and Bryce National Parks.r Besides this booklet, Walker wrote a studyr His specialty was paleontology.r While employed for the National Park Service he wroter of Triassic insects in Petrified Forest National Monument (1940),r where he also discovered vertebrate tracks.r He also wrote anr interpretative program study for Dinosaur National Monument (1943),r and Archeology of Zion Park (1955).r During 1955-1973 he was director of ther Division of Paleontology atr Fort Hays Kansas State College Museum.r

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r Walker married Wilda Opdyke in 1930.r They had one child, Margaret Jean Walker.r Wilda Walker died in 1980.r Myrl V. Walker died May 1985.r They are buried at Ft. Hays Memorial Gardens, Hays, Kansas.r In 1988 a series of paleontology papers were published asr “Articles in Honor of Myrl V. Walker,”r Fort Hays Studies, 3d ser. v. 10 (Science series).r

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Bibliographical Information

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r Myrl V. Walker (1903-1985),r Reptiles and Amphibians of Yosemite National Parkr (Yosemite: Yosemite Natural History Association, 1946)r “Special Number”r of Yosemite Nature Notes 25(1) (January 1946).r 48 pages. Illustrated. 24 cm.r Saddle stitched with yellow paper wrappers.r

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r Digitized by Dan Anderson, July 2005,r from a personal copy.r These files may be used for any non-commercial purpose,r provided this notice is left intact.r
r     —Dan Anderson, www.yosemite.ca.usr

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