ANIMAL LIFE IN THE YOSEMITE UNIVERSITY OF CALIFORNIA [GRINNELL-STORER] PLATE 1 SlKKKA XkVAIiA 1\(ISV l''l.\('ll ANIMAL LIFE IN THE YOSEMITE AN ACCOUNT OF THE MAMMALS, BIRDS, REPTILES, AND AMPHIBIANS IN A CROSS-SECTION OF THE SIERRA NEVADA BY JOSEPH GRINNELL AND TRACY IRWIN STORER Contribution from the Museum of Vertebrate Zoology University of California UNIVERSITY OF CALIFORNIA PRESS BERKELEY, CALIFORNIA 1924 Copyright, 1924 BY University of California Museum of Vertebrate Zoology J. Grinnell, Director Issued AprU 17, 1924 PREFACE The national parks of America render as their most important seiTice a full free opportunity to all who will to find in them a complete recreation, physical, mental, esthetic. In performing this service the animal life existing within their borders constitutes a valuable asset. For the best recreative forces in nature are those which ser\'e most quickly to call into play latent or seldom used faculties of mind and body whose exercise tends to restore to normal balance the human mechanism that has been disturbed by special or artificial conditions of living. Foremost among these forces are the living things that move and utter sounds, exhibit color and changing form, and by these qualities readily attract and fix our interest. To seek acquaintance with those primal objects of interest is to know the joy of vigorous muscular activity; better still, it is to realize the pos- session of the generally neglected senses of far-seeing and far-hearing, and to invite an esthetic appeal of the highest type and an intellectual stimulus of infinite resource. Of the thousands who each year visit the Yosemite Valley and its environs, a certain proportion are already interested in natural history; and anyone who leaves the region without gathering some definite knowledge of its natural history has failed to get adequate gain from his opportunities. The geology, topography, and botany of the Yosemite have been studied with some care; and there are instructive and stimulating manuals available dealing with these subjects. But heretofore only a few brief accounts have appeared in print concerning the bird life of the region, and practically nothing has been made available regarding its mammals, reptiles, and amphibians. It was in an effort to supply this deficiency that a survey of the vertebrate natural history of the Yosemite region was under- taken by the California Museum of Vertebrate Zoology. The present volume deals with the results of that survey. The principal objects in view in undertaking the survey were: To find out what species of mammals, birds, reptiles, and amphibians exist, or have within modern times existed, in the circumscribed area selected for study; to learn as much as possible concerning the local distribution of each of these species, and to map out the general life areas within the region; to learn as much as time permitted of the food relations, the breeding habits, and the behavior, individually, of each of the species; and finally to put all this information on permanent record, in a form accessible to, and generally assimilable by, the public, both lay anTichos 252 American Merganser, Mergus americanus 252 Mallard, -\nas platjThjTichos 253 Baldpate, Mareca americana 253 Cinnamon Teal, Querquedula cyanoptera 253 Shoveller, Spatula clypeata 254 Pintail, Dafila acuta 254 Harlequin Duck, Histrionicus histrionicus 255 American Bittern, Botaurus lentiginosus 256 Least Bittern, Ixobrychus exilis exilis 256 Great Blue Herons, Ardea herodias 256 California Great Blue Heron, Ardea herodias hyperonca Palhd Great Blue Heron, Ardea herodias treganzai Anthony Green Heron, Butorides virescens anthonyi 258 Black-crowned Night Heron, Nycticorax nycticorax naevius 259 Virginia Rail, Rallus virginianus 260 Mud-hen, FuUca americana .' 261 Northern Phalarope, Lobipes lobatus 261 Wilson Phalarope, Steganopus tricolor 262 Wilson Snipe, Gallinago delicata 263 Least Sandpiper, Pisobia minutilla 263 Spotted Sandpiper, Actitis macularia 263 Killdeer, Oxyechus vociferus vociferus 265 Mountain Quail, Oreortyx picta plumifera 267 Valley Quail, Lophortyx californica vallicola 270 Sierra Grouse, Dendragapus obscurus sierrae 272 Sage-hen, Centrocercus urophasianus 274 Band-tailed Pigeon, Columba fasciata fasciata 275 [X] PAGE Western Mourning Dove, Zenaidura macroura marginella 278 Turkey Vulture, Cathartes aura septentrionalis 279 White-tailed Kite, Elanus leucurus 281 Marsh Hawk, Circus hudsonius 281 Sharp-shinned Hawk, Accipiter velox 282 Cooper Hawk, Accipiter cooperi 284 Western Goshawk, Astur atricapillus striatulus 286 Western Red-tailed Hawk, Buteo boreaUs calurus 287 Red-bellied Hawk, Buteo lineatus elegans 289 Swainson Hawk, Buteo swainsoni 290 Ferruginous Rough-legged Hawk, Archibuteo ferrugineus 291 Golden Eagle, Aquila chrysaetos 292 Prairie Falcon, Falco mexicanus 294 Duck Hawk, Falco peregrinus anatum 294 Northern Pigeon Hawk, Falco columbarius columbarius 295 American Sparrow Hawk, Falco sparverius sparverius 296 American Osprey, Pandion haUaetus caroUnensis 297 Barn Owl, Tyto pratincola 298 Long-eared Owl, Asio wilsonianus 300 California Spotted Owl, Strix occidentalis occidentalis 304 Great Gray Owl, Scotiaptex nebulosa nebulosa 305 Saw-whet Owl, Cryptoglaux acadica 307 Southern California Screech Owl, Otus asio quercinus 308 Pacific Horned Owl, Bubo virginianus pacificus 309 Burrowing Owl, Speotyto cunicularia hypogaea 310 California Pigmy Owl, Glaucidium gnoma californicum 311 Road-runner, Geococcyx calif ornianus 313 Western Belted Kingfisher, Ceryle alcyon caurina 313 Modoc Woodpecker, Dryobates villosus orius 315 Willow Woodpecker, Dryobates pubescens turati 317 Nuttall Woodpecker, Dryobates nuttalli 319 Northern White-headed Woodpecker, Xenopicus albolarvatus albolarvatus 320 Arctic Three-toed Woodpecker, Picoides arcticus 326 Sierra Red-breasted Sapsucker, Sphyrapicus varius daggetti 327 Red-naped Sapsucker, Sphyrapicus varius nuchalis 330 WilHamson Sapsucker, Sphyrapicus thyroideus thyroideus 331 Northern Pileated Woodpecker, Phloeotomus pileatus abieticola 334 California Woodpecker, Melanerpes formicivorus bairdi 337 Lewis Woodpecker, Asyndesmus lewisi 341 Red-shafted Flicker, Colaptes cafer collaris 342 Poor-wills, Phalaenoptilus nuttalli 343 Dusky Poor-will, Phalaenoptilus nuttalli californicus Nuttall Poor-will, Phalaenoptilus nuttalli nuttalli Pacific Nighthawk, Chordeiles virginianus hesperis 346 Texas Nighthawk, Chordeiles acutipennis texensis 347 Northern Black Swift, Cypseloides niger borealis 349 Vaux Swift, Chaetura vauxi 35O White-throated Swift, Aeronautes melanoleucus 351 Black-chinned Hummingbird, Archilochus alexandri 352 Anna Hummingbird, Calypte anna 353 Rufous Hummingbird, Selasphorus rufus 354 Allen Hummingbird, Selasphorus alleni 355 Calliope Hummingbird, Stellula calliope 356 Western Kingbird, TsTannus verticalis 359 [xi] Ash-throated Flycatcher, Myiarchus cincrascens einerascens 360 Say Phoebe, Sayornis sayus ■ •••■• •*• 362 Black Phoebe, Sayornis nigricans .' ■.....-.....: ...• 362 Olive-sided Flycatcher, Nuttallornis borealis .-• - 364 Western Wood Pewee, Myiochanes richardsoni richardsoni — ... 365 Wright P\vcatcher, Empidonax wrighti ....- -. 367 Hammond Flycatcher, Empidonax hammondi .- ...:- 370 Traill Flycatcher, Empidonax trailli trailh 371 Western Flycatcher, Empidonax difficilis difficilis 372 Gray Flycatcher, Empidonax griseus 373 Horned Larks, Otocoris alpestris •- 374 Cahfornia Horned Lark, Otocoris alpestris actia Dusky Horned Lark, Otocoris alpestris merrilU Black-billed Magpie, Pica pica hudsonia 376 Blue-fronted Jay, Cyanocitta stelleri frontalis 379 Interior California Jay, Aphelocoma californica immanis 387 Woodhou.se Jay, Aphelocoma woodhousei 392 Western Raven, Corvus corax sinuatus 392 Western Crow, Corvus brachyrhynchos hesperis 392 Clark Nutcracker, Nucifraga columbiana 393 Pifion Jay, Cyanocephalus cyanocephalus 397 Cowbirds, Molothrus ater 398 Dwarf Cowbird, Molothrus ater obscurus Nevada Cowbird, Molothrus ater artemisiae Yellow-headed Blackbird, Xanthocephalus xanthocephalus 399 Red-winged Blackbirds, Agelaius phoeniceus 400 Bi-colored Red-winged Blackbird, Agelaius phoeniceus californicus Nevada Red-winged Blackbird, Agelaius phoeniceus nevadensis Kern Red-winged Blackbird, Agelaius phoeniceus aciculatus Tri-colored Blackbird, Agelaius tricolor 407 Western Meadowlark, Sturnella neglecta 409 Bullock Oriole, Icterus buUocki 411 Brewer Blackbird, Euphagus cyanocephalus 413 California Evening Grosbeak, Hesperiphona vespertina californica 417 California Pine Grosbeak, Pinicola enucleator californica 419 California Purple Finch, Carpodacus purpureus californicus -120 Cassin Purple Finch, Carpodacus cassini 423 California Linnet, Carpodacus mexicanus frontalis 426 Sierra Crossbill, Loxia curvirostra bendirei 428 Sierra Nevada Rosy Finch, Leucosticte tephrocotis dawsoni 430 Willow Goldfinch, A.stragalinus tristis salicamans 434 Green-backed Goldfinch, Astragalinus psaltria hesperophilus 435 Lawrence Goldfinch, Astragalinus lawrencei 437 Pine Siskin, Spinus pinus pinus 438 English Sparrow, Passer domesticus 439 Vesper Sparrows, Pooecetes gramineus 440 Western Vesper Sparrow, Pooecetes gramineus confinis Oregon Vesper Sparrow, Pooecetes gramineus affinis Savannah Sparrows, Pas.serculus sandwichcnsis 442 Aleutian Savannah Si)arrow, Pa.sserculus sandwichcnsis sinulwichensis Western Savannah Sparrow, Pa.sserculus sandwichcnsis alaudiiuis Nevada Savannah Sparrow, Passcrculus sandwiciiciisis nevadensis Western Grasshopper Sparrow, Amiiiodrainus savannarum l)iinaculatus 443 Western Lark Sparrow, Chondestes grainmacus strigatus 444 [xii] PAGE White-crowned Sparrows, Zonotrichia leucophrys 446 Hudsonian White-crowned Sparrow, Zonotrichia leucophrys leucophrys Intermediate White-crowned Sparrow, Zonotrichia leucophrys gambeli Golden-crowned Sparrow, Zonotrichia coronata 450 Western Chipping Sparrow, Spizella passerina arizonae 452 Brewer Sparrow, Spizella breweri 456 Black-chinned Sparrow, Spizella atrogularis 458 Slate-colored Junco, Junco hyemalis hyemalis 458 Sierra Junco, Junco oreganus thui-beri 459 Shufeldt Junco, Junco oreganus shufeldti Bell Sparrow, Amphispiza belli 464 Nevada Sage Sparrow, Amphispiza nevadensis nevadensis 466 Rufous-crowned Sparrow, Aimophila ruficeps ruficeps 467 Song Sparrows, Melospiza melodia 468 Modoc Song Sparrow, Melospiza melodia fisherella Rusty Song Sparrow, Melospiza melodia rufina Heermann Song Sparrow, Melospiza melodia heermanni Merrill Song Sparrow, Melospiza melodia merrilli Lincoln Sparrows, Melospiza lincolni 470 Northeastern Lincoln Sparrow, Melospiza lincolni lincolni Northwestern Lincoln Sparrow, Melospiza lincolni gracilis Fox Sparrows, Passerella iliaca 472 Shumagin Fox Sparrow, Passerella iliaca unalaschcensis Kadiak Fox Sparrow, Passerella iliaca insularis Valdez Fox Sparrow, Passerella iliaca sinuosa Alberta Fox Sparrow, Passerella iliaca altivagans Slate-colored Fox Sparrow, Passerella iliaca schistacea Mariposa Fox Sparrow, Passerella iliaca mariposae Mono Fox Sparrow, Passerella iliaca monoensis Thick-billed Fox Sparrow, Passerella iliaca megarhyncha Spurred Towhees, Pipilo maculatus 477 Sacramento Spurred Towhee, Pipilo maculatus falcinellus Nevada Spurred Towhee, Pipilo maculatus curtatus Northern Brown Towhee, Pipilo crissalis carolae 480 Green-tailed Towhee, Oberholseria chlorura 482 Pacific Black-headed Grosbeak, Zamelodia melanocephala capitalis 484 California Blue Grosbeak, Guiraca caerulea salicarius... 490 Lazuli Bimting, Passerina amoena 491 Western Tanager, Piranga ludoviciana 493 Western Martin, Progne subis hesperia ; 497 Cliff Swallow, Petrochelidon lunifrons lunifrons 497 Barn Swallow, Hirundo erythrogaster erythrogaster 499 Tree Swallow, Iridoprocne bicolor 500 Northern Violet-green Swallow, Tachycineta thalassina lepida 501 Rough-winged Swallow, Stelgidopteryx serripennis 503 Bohemian Waxwing, Bombycilla garrula 604 Cedar Waxwing, Bombycilla cedrorum 504 Phainopepla, Phainopepla nitens 505 Shrikes, Lanius ludovicianus 506 California Shi-ike, Lanius ludovicianus gambeli White-rumped Shrike, Lanius ludovicianus excubitorides Western Warbling Vireo, Vireosylva gilva swainsoni 508 Cassin Vireo, Lanivireo solitarius cassini 511 Hutton Vireo, Vireo huttoni huttoni 513 [xiii] PAGE California Least Vireo, Vireo belli pusillus 514 Calaveras Warbler, Vermivora ruficapilla gutturalis 516 Orange-crowned Warblers, Vermivora celata 519 Lutescent Warbler, Vermivora celata lutescens Rocky Mountain Orange-crowned Warbler, Vermivora celata orestera California Yellow Warbler, Dendroica aestiva brewsteri 521 Alaska Myrtle Warbler, Dendroica coronata hooveri 523 Audubon Warbler, Dendroica auduboni auduboni 524 Black-throated Gray Warbler, Dendroica nigrescens 529 Townsend Warbler, Dendroica townsendi 531 Hermit Warbler, Dendroica occidentalis 532 Tolmie Warbler, Oporornis tolmiei. 534 Yellowthroats, Geothlypis trichas 538 Western Yellowthroat, Geothlypis trichas occidentaUs Tule Yellowthroat, Geothlypis trichas scirpicola Long-tailed Chat, Icteria virens longicauda 539 PUeolated Warblers, Wilsonia pusilla 540 Golden Pileolated Warbler, Wilsonia pusilla chryseola Alaska Pileoated Warbler, Wilsonia pusilla pileolata American Pipit, Anthus rubescens 542 American Dipper, Cinclus mexicanus unicolor 543 Sage Thrasher, Oreoscoptes montanus 546 Western Mockingbird, Mimus polyglottos leucopterus 547 California Thrasher, Toxostoma redivivura redivivum 548 Rock Wren, Salpinctes obsoletus obsoletus 550 Dotted Canon Wren, Catherpes mexicanus punctulatus 552 San Joaquin Bewick Wren, Thryomanes bewicki drymoecus 555 Western House Wren, Troglodytes aedon parkmani 556 Western Winter Wren, Nannus hiemalis pacificus 558 Western Marsh Wren, Telmatodytes palustris plesius 560 Sierra Creeper, Certhia familiaris zelotes 561 Slender-billed Nuthatch, Sitta carolinensis aculeata 564 Red-breasted Nuthatch, Sitta canadensis 568 Pigmy Nuthatch, Sitta pygmaea pygmaea 571 Plain Titmouse, Baeolophus inornatus inornatus 572 Short-tailed Mountain Chickadee, Penthestes gambeli abbreviatus 574 California Bush-tit, Psaltriparus minimus californicus 579 Lead-colored Bush-tit, Psaltriparus plumbeus 582 PaUid Wren-tit, Chamaea fasciata henshawi 582 Western Golden-crowned Kinglet, Regulus satrapa olivaceus 586 Western Ruby-crowned Kinglet, Regulus calendula cineraccus 589 Western Gnatcatcher, Polioptila caerulea obscura 593 Townsend Solitaire, Myadestes townsendi 595 Russet-backed Thrush, Hylocichla ustulata ustulata 600 Hermit Thrushes, Hylocichla guttata 602 Sierra Hermit Thrush, Hylocichla guttata sequoiensis Alaska H(!rmit Thrush, Hylocichla guttata guttata Dwarf Hermit Thrush, Hylocichla guttata nanus Western Robin, Planesticus migratorius propinquus 605 Northern Varied Thrush, Ixoreus nacvius moruloides 614 Western Bluebird, Sialia mexicana occidentalis 615 Mountain Bluebird, Sialia cunucoidcs 622 fxiv] PAGE The Reptiles 626 Blue-bellied Lizards, Sceloporus occidentalis 626 Western Fence Lizard, Sceloporus occidentalis occidentalis Pacific Blue-bellied Lizard, Sceloporus occidentalis bi-seriatus Tenaya Blue-bellied Lizard, Sceloporus occidentalis taylori Mountain Lizard, Sceloporus graciosus graciosus 628 California Horned Toad, Phrynosoma blainvillii frontale 630 Alligator Lizards, Genus Gerrhonotus 630 San Diego Alligator Lizard, Gerrhonotus scincicauda webbii Sierra Alligator Lizard, Gerrhonotus palmeri CaUfornia Whip-tailed Lizard, Cnemidophorus tigris mundus 632 Western Skink, Plestiodon skiltonianus 633 Rubber Snake, Charina bottae 635 Garter Snakes, Genus Thamnophis 636 Pacific Garter Snake, Thamnophis sirtalis infernalis Giant Garter Snake, Thamnophis ordinoides couchii Mountain Garter Snake, Thamnophis ordinoides elegans Wandering Garter Snake, Thamnophis ordinoides vagrans Western Ring-necked Snake, Diadophis amabilis amabilis 639 Coral King Snake, Lampropeltis multicincta 640 Boyle King Snake, Lampropeltis getulus boylii 640 California Striped Racer, Coluber lateralis 641 Western Yellow-bellied Racer, Coluber constrictor flaviventris 643 Valley Gopher Snake, Pituophis catenifer heermanni 643 Pacific Rattlesnake, Crotalus oreganus 645 Pacific Mud Turtle, Clemmys marmorata 650 The Amphibians 651 Pacific Coast Newt, Notophthalmus torosus 651 Mount Lyell Salamander, Eurycea platycephala 652 Arboreal Salamander, Aneides lugubris lugubris 653 Slender Salamander, Batrachoseps attenuatus 654 Western Spade-foot Toad, Scaphiopus hammondii hammondii 654 California Toad, Bufo boreas halophilus 655 Northwestern Toad, Bufo boreas boreas Yosemite Toad, Bufo canorus P57 Pacific Tree-toad, Hyla regilla 661 Yellow-legged Frogs, Rana boylii 663 California Yellow-legged Frog, Rana boylii boylii Sierra Yellow-legged Frog, Rana boylii sierrae California Red-legged Frog, Rana aurora draytonii 666 Bibliography: Articles relating chiefly or importantly to the vertebrate animals of the Yosemite section, published up to the end of 1920 667 Index 743 Plates, Colored plate (scattered through the text) 1. Sierra Nevada Rosy Finch frontispiece OPPOSITE PAGE 2. Sierra Golden-mantled and Belding ground squirrels; Marmot 158 3. Chipmunks of the Yosemite section 182 4. Band-tailed Pigeon 278 5. Woodpeckers of the Yosemite section 326 6. Family group of WilUamson Sapsuckers 334 [XV] PLATE OPPOSITE PAGE 7. Cassin and California purple finches and California Linnet 422 8. Some sparrows of the Yosemite section 454 9. Warblers of the Yosemite section 518 10. Some small birds of the Yosemite forests 566 11. Townsend Solitaire and Russet-backed and Sierra Hermit thrushes 598 12. Coral King Snake; Western Skink, young and adult 630 Plates, Half-tone (in signatures at end of text) page 13. Merced River bottom near SncUing; blue oak in winter, with mistletoe 671 14. Digger pine association near Pleasant Valley; edge of yellow pine association three miles east of Coulterville 673 15. Golden oak association near Rocky Point; south bank of Merced River near El Portal 675 16. Yosemite Valley from Big Oak Flat road, with golden-oak talus in foreground; meadow and cottonwood associations in Yosemite Valley 677 17. Jeffrey pine and huckleberry oak associations east of Half Dome; white fir associa- tion near Chinquapin 679 18. Vogelsang Lake and Pass; Tuolumne Meadows 681 19. Mounts Gibbs and Dana from the east; Williams Butte near Mono Lake 683 20. Navigator, Yosemite and Dusky shrews 685 21. Bats of the Yosemite Valley and higher Sierra Nevada 687 22. Tracks of Black Bear in Yosemite Valley 689 23. Pacific Fisher, Sierra Pine Marten and Sierra Nevada Wolverine 690 24. California Badger and its work 691 25. Boyle and Common white-footed mice and House Mouse 692 26. Some "leaping" rodents of the Yosemite section 693 27. Yosemite Pocket Gopher and Yosemite Mole '■ 695 28. Surface workings of mole and pocket gopher 697 29. Yosemite Pocket Gopher in action 699 30. Winter earth cores made by pocket gophers 701 31. Sierra Mountain Beaver and its burrow 702 32. Southern Sierra Marmot 703 33. Long-eared Chipmunk and California Gray Squirrel 704 34. California Gray Squirrel 705 35. Cones of white fir exhumed from caches made by Sierra Chickaree; twig tips of lodgepole pine cut by Sierra Chickaree 707 36. Granite talus at head of Lyell Canon, home of Yosemite Cony; kitchen middens on log where Sierra Chickaree had been dissecting red fir cones 709 37. Work of Yellow-haired Porcupine; work of Golden Beaver 711 38. Yosemite Cony and its lookout station 712 39. Mountain Coyote; Mule Deer 713 40. Records in the road 715 41. Cahfornia Gulls on Paoha Island, Mono Lake 717 42. Long-eared Owls 718 43. Band-tailod Pigeons; Nuttall Poorwill; Groat Gray Owl 719 44. Principal diurnal birds of prey in the Yosemite region 720 45. Nests and eggs of Swainson Hawk and Texas Night hawk 721 46. Hummingbirds, Swallows, and White-throated Swift 723 47. Nests of Cliff Swallow and California Linnet 724 48. Marii)osa Fox Sparrow, Green-tailed Towhee, and Sacramento Spurred Towhee.. 725 49. Ne.sts of (Jreon-tailed Towhee and Northeastern Lincoln Sparrow 726 50. Vireos of the Yosemite region 727 [xvi] PLATE PAGE 51. Nests of California Least Vireo and Tolmie Warbler 728 52. American Dipper 729 53. Western Mockingbird and California Shrike; Dotted Canon Wren and San Joaquin Bewick Wren 731 54. Western House Wren and nest sites 733 55. Nests of Western Robin and Townsend Solitaire 734 56. Black-billed Magpie and Mountain Bluebird 735 57. Mountain Lizard, Western Fence Lizard and California Whip-tailed Lizard 736 58. Western Skink and alligator lizards 737 59. Valley Gopher Snake and Pacific Rattlesnake 739 60. Some amphibians of the Yosemite region 741 Maps, Colored (at end of half-tone plates) 61. Profile of Yosemite section showing relation of life-zones to altitude and slope 62. Map showing life-zones of Yosemite section Figures in Text FIGURE page 1. Zonal restriction of certain mammals 5 2. Zonal restriction of certain breeding birds 7 3. Sample census sheet 23 4. Snout of Yosemite Mole 43 5. Fore foot of Yosemite Mole and of Sierra Nevada Pocket Gopher 44 6. Zonal distribution of shrews 48 7. Pacific Pallid Bat 61 8. Mexican Free-tailed Bat 62 9. Sierra Least Weasel, Mountain Weasel and Pacific Mink 87 10. Heads of white-footed mice 105 11. Zonal distribution of white-footed mice 107 12. Tails of Alexandrine Roof Rat, and of Streator and Gray Bushy-tailed wood rats 116 13. Streator Wood Rat 117 14. Nesting quarters of Streator Wood Rat in log 119 15. Gray Bushy-tailed Wood Rat 121 16. Tails of Yosemite Meadow Mouse and Sierra Cantankerous Meadow Mouse 123 17. Burrow-system of Mariposa Meadow Mouse 128 18. Enlarged section through part of preceding 129 19. Zonal distribution of meadow mice 130 20. Sierra Cantankerous and Yosemite meadow mice and Mountain Lemming Mouse 131 21. Willow association at head of Lyell Canon 132 22. Method of work of mole 136 23. Method of work of pocket gopher 137 24. Zonal distribution of pocket gophers 139 25. Cartoon suggesting relation of pocket gopher work in high mountains to accumu- lation of fertile sediments in lowlands 143 26. Quill of Yellow-haired Porcupine 152 27. Zonal distribution of squirrels and marmot 163 28. Zonal distribution of chipmunks 178 29. Sierra Chickaree 205 30. Sugar pine cones as worked upon by Sierra Chickaree 206 31. Kitchen middens: remains of cones of Jeffrey pine 207 32. Sierra Flying Squii-rel 212 33. Head of California Jack Rabbit 223 [xvii] FIGURE PAGE 34. Head of Sierra White-tailed Jack Rabbit 225 35. Heads of Mariposa Brush Rabbit and Sacramento Cottontail Rabbit 229 36. Skulls and horns of Sierra Nevada Mountain Sheep and Domestic Sheep 245 37. Harlequin Ducks 255 38. Debris from beneath Cooper Hawk's nest 285 39. Owls of the Yosemite region 299 40. Debris from beneath Long-eared Owl's nest 303 41. Work of Willow Woodpecker on apple tree 319 42. Feet of Northern White-headed Woodpecker and Arctic Three-toed Woodpecker 326 43. Diagram of workings of Sierra Red-breasted Sapsucker 328 44. Fresh work of Williamson Sapsucker 332 45. Scars on trunk of lodgepole pine, result of work of Williamson Sapsucker 333 46. Head of Northern Pileated Woodpecker 335 47. Head and tongue of California Woodpecker 339 48. Drillings of California Woodpecker and nest site of Lewis Woodpecker 340 49. Head of Clark Nutcracker 395 50. Tails of California Purple Finch and California Linnet 421 51. Bill of Sierra Crossbill and cone and seeds of lodgepole pine 430 52. Bills of Cassin Purple Finch, California Evening Grosbeak, and Sierra Nevada Rosy Finch 431 53. Tails of Willow, Green-backed, and Lawrence goldfinches, and Pine Siskin 436 54. Tails of Western Lark Sparrow and Western Vesper Sparrow 444 55. Young of Mariposa Fox Sparrow and Pacific Black-headed Grosbeak 489 56. Forage niches of warblers in Yosemite Valley 517 57. Tails of Alaska Myrtle Warbler and Audubon Warbler 527 58. Tails of Sierra Creeper and Red-breasted Nuthatch 562 59. Heads of Sierra Hermit Thrush and Cassin Purple Finch 604 60. Young Western Robin 607 61. Zonal distribution of certain reptiles and amphibians 627 62. Western Yellow-bellied Racer and Giant Garter Snake 637 63. Boyle King Snake and California Striped Racer 641 64. Rattle of Pacific Rattlesnake 647 65. Poi.son apparatus of Pacific Rattlesnake 649 INTRODUCTION The Area Considered The region studied is designated in this report as the ' Yosemite region, ' or, more precisely, as the ' Yosemite section. ' It involves, as shown on the accompanying map (pi. 62), a narrow rectangular area, 89l^ miles in length by 17 1/3 miles in width. It reaches from the eastern margin of the San Joaquin Valley eastward across the mountains to include the western margin of the Great Basin, around Mono Lake, and thus constitutes a typical cross-section of the central Sierra Nevada. The altitudes range from 250 feet, at Snelling, to slightly over 13,000 feet, on Mount Lyell. The total 'map' area is 1547 square miles, Yosemite Valley is included in its entirety ; the Valley ends of the Wawona and Big Oak Flat roads are within the ' section, ' as are the greater parts of the Coulterville and Tioga roads. But neither the Mariposa Grove of Big Trees nor Hetch Hetehy Valley is included. Within the limits of this 'section,' the members of our field party traveled over most of the regular trails (routes are shown on the map) ; in addition they sought out high pointSffrom which practically every square mile of territory could be seen and mapped as to life zone. All together, 40 collecting stations were occupied by different members of our party. The number of persons working at any one station at one time varied from one to five. Certain camps such as those in Yosemite Valley, at Porcupine Flat, on Tuolumne Meadows, and at the Farrington ranch were 'base camps, ' from which short trips were taken in different directions. At all the places marked on the map as collecting stations, trapping for mammals was done on one or more nights. Statistics of Field Work The first regular field work of the Yosemite Survey was a reconnaissance trip by the senior author in the autumn of 1914. (Both authors were already familiar with the lay of the land from previous visits to Yosemite Valley and its environs.) Formal field work was instituted on Novem- ber 19, 1914, and continued until January 9, 1915; it was commenced again on May 15, 1915, and continued until July 31 ; it was again taken up on August 16 and carried on until November 23 (1915). In 1916 continuous work was carried on in the neighborhood of Mono Lake from [1] 2 ANIMAL LIFE IX THE TOSEMITE April 26 until July 6, That same year, two brief trips were made into Yosemite Valley, at the end of February and at the end of April. In IDli) work in the western part of the region was carried on from May 5 to 27 ; and in 1920 work was in progress there from June 20 until August 11. Nine hundred and fifty-seven 'man-days' (one man in the field one day) were put in. The field notes written occupy 2001 pages, and the specimens secured bj' our regular field men number 4354. The photographs obtained number 700. In addition, as indicated elsewhere, much valuable information and many important specimens were secured from residents in the Yosemite region. All the materials upon which this report is based, including specimens, maps, notebooks, and photographs, are now contained in the Museum of Vertebrate Zoology of the University of California and are the property of the State of California. Field Personnel Eight different persons participated at one time or another in the field work of the Yosemite Survey; 248 days were put in by Joseph Grinnell, 170 days by Tracy I. Storer, 111 days by AValter P. Taylor, 110 days by Joseph Dixon, 103 days by Charles L. Camp, 92 days by Gordon F. Ferris, 91 days by Charles D. Holliger, and 32 days by Donald D. McLean. It should be understood that whatever degree of accuracy and fullness the present report may possess rests upon the diligence, as field collectors and observers, of each and every one of these persons. FiEi>D Methods The general plan of work was much the same at all the collecting stations. It was of course essential, in the interests of truth and scientific accuracy, that many specimens be obtained in order that correct identi- fication of the species might be insured. Hence, each member of the party kept out a line of mouse and rat traps for the capture of the various species of small mammals. These were set in 'likely' places: along stream banks for shrews ; in runways of meadow mice ; about brush heaps or downed logs for Avhite-footed mice, and so on. Special traps were set for moles, for pocket gophers, and for carnivoro\is species. These traps were baited the last thing each evening and were visited early the next morning so as to collect the animals caught before they might be harmed by sunshine or by insects. Where chipmunks abounded, or ground dwelling birds were numer- ous, traps were often visited during the day to recover such animals as were caught; or else the traps Avere pur])osely spning in the morning and reset again in the evening in order 1o avoid capturing nianunals or birds not needed i'or specimens. IJirds were ol)!. 'lined, when necessary, by s]u)oling INTRODUCTION 3 selected individuals. Many reptiles were captured* by hand, although some of the swifter ones could be obtained only by shooting. But the taking of specimens was only one of several lines of activity. The morning of each day was usually spent away from camp observing and making notes upon the various species to be seen — their local distri- bution, forage habits, nesting behavior, and all the other observable features connected with their life histories. Each member of the party carried a notebook (journal) in which the observations of each day were recorded. Notes on the behavior of individual animals were written down usually while observation was in progress, to insure the entry of details with accuracy. When nests, burrows, or other 'workings' were examined, the measurements and diagrams were entered directly in the journal. Censuses were gathered as they were taken, the individuals pencil-checked one by one according to the method described fully elsewhere (p. 22). Photographs were taken of 'associations,' workings, tracks, and nests, and these mater- ially supplemented the written data. Limitation of Time It became necessary, as in all such undertakings as this, arbitrarily to fix upon a date beyond which no further matter would be incorporated into this report. This date was set as December 31, 1920. Even though important new facts have been reported from the Yosemite region by competent observers since that date, we have forborne inclusion thereof. Inevitably, such additions will continue to be made so long as people with an interest in natural history visit the Yosemite region. The natural history resources will never become exhausted ; and that is one fascinating feature of this field of inquiry. Our efforts, then, have been to assemble all the available information concerning the vertebrate animals of the Yosemite region up to and including December, 1920. ANIMAL LIFE IN THE YOSEMITE DISTRIBUTION OF ANIMAL LIFE IN THE YOSEMITE SECTION Probably the primary stimulus which leads people to visit our national parks is the change that is experienced from familiar surrounding to those which are emphatically different. This change involves 'air' (that is, climate), and 'scene' (topography and vegetation). An entirely new set of conditions is encountered, and the new reactions set up mean recreation in the physiological sense — the exercise of faculties, both mental and physical, in kind or degree, that are more or less dormant during the ordinary routine of the year's program. Quick transportation between the lowlands of the San Joaquin Valley and the upper altitudes of the Sierras carries the traveler in either direction from one set of surroundings into a totally different one where he is thrilled because of the great changes which he encounters. Let us now discuss, then, these differences in environment and their correlation with the continuous or discontinuous occurrence of vertebrate animals in the region. The section of the Sierra Nevada selected for faunal study is of such extent transversally to the Sierran axis that it takes in almost as great extremes of conditions as are to be encountered anywhere in California. Analysis of the changes to be observed as a person traverses the section from the west ^^^ll soon show that he has witnessed not one single change, evenly and progressively from one set of conditions to just one other set, but that, having reached the highest altitudes, he has witnessed several steps. There has not been a uniform and continual gradient but he has passed through several belts, parallel roughly to the axis of the Sierra Nevada, each characterized by a considerable degree of uniformity as regards the plant and animal life. A total of 231 kinds of birds are now (December 31, 1920) authentically known from the Yosemite section ; there are 97 kinds of mammals, 22 kinds of snakes and lizards, and 12 kinds of frogs, toads, and salamanders. This makes a grand total, for the vertebrate fauna outside of fishes, of 362 forms. This seeming richness in number of kinds, be it emphasized, is apparent only when one takes into account the full extent of the Yosemite section. As a matter of fact, but a small proportion of the total number of species occur together at any one level. And here is the remarkable thing: They are more or less assorted and delimited in occurrence so that tlioy helji to constitute the belts, or 'life zones,' just referred to. DISTRIBUTION OF THE ANIMALS Tule Meadow Mouse Merced Kangaroo Rat Fresno Pocket Gopher Golden Beaver San Joaquin Pocket Mouse Sacramento Cottontail Rabbit Cascade Red Fox Yellow-haired Porcupine Allen Chipmunk Sierra Wolverine Sierra Least Weasel Mountain Lemming Mouse Southern Sierra Marmot Belding Ground Squirrel Alpine Chipmunk Yosemite Cony Alpine Chipmunk ' Yosemite Cony ■ Mono Chipmunk Mono Mole Short-tailed Grasshopper Mouse Great Basin Pocket Mouse , Pale-faced Kangaroo Rat ?s Mono Kangaroo Mouse Desert Jack Rabbit Sagebrush Chipmunk Washington Cottontail Rabbit 6 ANIMAL LIFE IN TEE YOSEMITE We may express the facts in another way. The large number of kinds of animals present in the entire Yosemite section is due to the great range of physical conditions (temperature, moisture, soil, light, and perhaps others) with the accompanying diversity of vegetational features. Man is able to traverse the whole gamut of these conditions, even with benefit to himself by reason of the stimulus change produces, adjusting his mode of dress and behavior to them and carrying his food with him. But animals and plants are more or less directly in contact with the conditions around them ; they are, as a rule, far less adaptable ; and they are vitally affected by differences in temperature, in moisture, in food supply, and so on. The interesting thin^ is that in many species the degree of sensitiveness is so great that they can maintain existence only \vithin a relatively narrow range of the critical conditions. Such underlying reasons as those just suggested help to explain what impresses the traveler in ascending the west slope of the Sierras, namely, the correlation, roughly, with respect both to animals and plants, of zonation with altitude and, therefore, temperature. And it is because of this inter-correlation that the student is led to the conclusion that it is the factor of temperature which has most to do with the causation of life zones. Reference to our map and cross-section diagram (pis. 61, 62) will show the application, to the Yosemite section, of the system of recognizing these belts of animal and plant life as some naturalists have worked them out and named them. Each life zone is a belt of relatively uniform constitution with respect to species. At the same time, we must emphasize that there is rarely an abrupt line of demarcation between any two adjoining zones. There is, as a rule, along the meeting ground more or less mixing or over- lapping of the specific elements. Tliis is especially true where the slope is very gentle, broad, and all facing in one direction. The steeper the slope, or the more abrupt the change of exposure (say from west to north), the sharper will be the boundary between the two adjacent zones. To enter here into a further discussion of the life-zone concept is not necessary. We will simply refer the inquiring reader to some of the literature relating to the subject^ and confine the present treatise to the iC. Hart Merriam, Life Zones and Crop Zones of the United States (U. S. Dept. Agric, Div. Biol. Surv., Bull. no. 10, 1898), 79 pp., 1 colored map. C. Hart Morriam, Eesults of a Biological Survey of Mount Shasta, California (U. S. Dopt. Agric, Div. Biol. Surv., N. Am. Fauna, no. 16, 1899), 179 pp., 5 pis., 46 figs, in text. H. M. Hall, A Botanical Survey of San Jacinto Mountain (TTniv. Calif. Puhl. Bot., vol. 1, 1902), l)p. 1-140, pis. 1-14. J. Grinnell, An Account of the Mammals and Birds of the Lower Colorado Valley, with Especial Reference to the Distributional Probleius Presented (Univ. Calif. Publ. Zool., vol. 12, 1914), pp. .'51-294, pis. 3-13, 9 figs, in text. J. Grinnell, A Distributional List of the Birds of California (T'ac. Coast Avifauna, no. 11, 1915), 217 pp., 3 maps. H. M. Hall and J. Grinnell, T^ife Zone Indicators in California (Proc. Calif. Acad. Sci., ser. 4, vol. 9, 1919), pp. 37-67. DISTBIBUTION OF THE ANIMALS Sierra Grouse Western Goshawk Williamson Sapsucker Hammond Flycatcher Cassin Purple Finch Mariposa Fox Sparrow Townsend Solitaire Arctic Three-toed Woodpecker . California Pine Grosbeak Hudsonian White-crowned Sparrow Sierra Nevada Rosy Finch Hudsonian White-crowned Sparrow 8 ANIMAL LIFE IX THE TOSEMITE particular state of affairs found in the Yosemite region. Since all animal life is more or less directly dependent upon plant life for its existence, the zoologist who seeks to explain the distribution of animals must concern himself attentively also -with the botany of the region he is studying. A very useful essay on the distribution of plant life on the upper western slope of the Yosemite section is contained in Professor and Mrs. Hall's Yosemite Flora-; and further valuable data on the distribution of plants in the Sierras will be found in a report by Dr. Smiley.^ All of the six life zones in the Yosemite region are represented in full measure on the western slope of the section. There the distance involved in the slope is so great, over seventy miles, that there is plenty of room for the development of a separate representation of species, both plant and animal, in each zone. But on the eastern slope the situation is some- what different ; and we find the zonation there obscure. Indeed, in our field work below the Hudsonian Zone we met with much trouble in diagnosing many of the localities; for instance, whether to call the upper meadows on the Farrington ranch (pi. 19a.), Canadian or Transition; the south face of Williams Butte (pi. 196), Transition or Upper Sonoran. On the basis of the facts obtained within the eastern boundary of our Yosemite section alone, the situation would be exceedingly difficult, even impossible, of explanation. But when we take into account the ea.st-Sierran region generally, especially toward the southern end of the Sierran ridge in the vicinity of Walker and Tehachapi passes, it becomes fairly easy to see why conditions are as we find them between Mono Lake and Mono and Tioga passes. Base-level in the Mono Basin is high, averaging 7000 feet in altitude. Furthermore, the distance between Mono Lake and the high Sierran crest, which is 10,000 to 13,000 feet in altitude, is short. In other words, this slope is abrupt ; in fact, close to the divide, a declivity. The life zones, in so far as characteristic representatives of them are to be found, are crowded together — telescoped, as it were. There is a well established law that a sequestered faunal area can be too small to support a permanent, distinctive fauna of its own, even though conditions be otherwise wholly propitious. The Sierra Nevada, which by area is of mainly western slope, supports a large mass of 'boreal' plant and animal life; the Great Basin area to the east is the metropolis of a highly developed 'austral' assemblage of species. These two major areas adjoin one another at the steep eastern declivity of the Sierras. On the long western slope where austral adjoins 2H. M. Hall and C. C. Hall, A Yosemite Flora (Paul Elder, San Francisco, 1912), pp. viii + 282, 170 text figs., 11 pis. 3 F. J. Smiley, A Rejjort upon the Boreal Flora of the Sierra Nevada of California (Univ. Calif. Publ. Bot., vol. 9, 1921), pp. 1-423, pis. 1-7. DISTBIBUTION OF THE ANIMALS 9 boreal there is not only a well-marked belt of overlapping (comprising the Transition Zone) but in this belt there are numerous species closely restricted to it. On the eastern slope, however, Canadian and Upper Sonoran are jammed so closely together by reason of the steepness that the belt of intermingling of elements is very narrow or at best indistinct ; there is scarcely if any room for the existence of restrictedly Transition Zone species. Although presenting a strongly Great Basin aspect, the Mono basin, doubtless because of its high altitude, does not show a pure representation of austral life. It does contain a number of elements (that is, species) which from a study of their entire ranges we know to belong predominantly to the upper division of the austral, namely Upper Sonoran. But there are also present about as many, or as dominant, boreal elements. Frankly, we found difficult}^ in assigning some parts of the Mono portion of the Yosemite section to one life zone rather than to another. This was particularly true of the south, sun-facing slope of Williams Butte (pi. 19&), which is clothed with piiion. This tree to the southward along the Sierras forms a belt which through Walker Pass is continuous with the digger pine belt of the west slope of the Sierras ; and as a rule we can safely diagnose this belt by reason of this one plant indicator as Upper Sonoran. But on Williams Butte the pinons are mixed with western junipers, Jeffrey pines, mountain mahogany, and certain shrubby plants which are accepted as diagnostic of Transition, Canadian, or even Hudsonian. We found in this anomalous assemblage of plants such 'good' Upper Sonoran birds as bush-tits and Woodhouse jays in close association with mountain chickadees and Clark nutcrackers. This was after the breeding season ; and, of course, there was a chance that in the case of the last-named species, at least, the individuals observed had moved down from the higher altitudes but a very few miles to the westward. In the case of small mammals, which are incapable of quickly traversing considerable stretches of territory, we found, on Williams Butte, True white-footed mice, which are typically Upper Sonoran, in the same trap-line with Mono chipmunks, which find their metropolis in the Canadian life zone. Another tract in the Mono country which was for similar reasons perplexing occupies the lower slope down toward the lake shore from Mono Mills. There, pale-faced kangaroo rats, Stephens soft-haired ground squirrels, and desert jack rabbits were found, species which belong to groups whose habitats lie chiefly within the Upper Sonoran Zone, but here were found in company with animals and plants of more northern, Transition or even Canadian, predilections. The sage-hen, to cite one of these latter, is a ' good ' Transition bird. 10 ANIMAL LIFE IX THE 10 SEMITE 111 the nature of the case, as regards these exceptional localities, we trust that the reader will understand why it is impossible for us to make, positive statements witli regard to their zonal complexion. Two persons, with some difference in perspective — that is, witli a different understanding of the 'importance' of indicators — would very probably weight tlieir find- ings differently. Our conclusion, as shown on our map and in our life-zone table, namely, to call the western part of the Mono Lake basin, that part, included within the Yosemite 'section,' Transition, is therefore presented tentatively. The margin of determination is so small, with regard especially to Williams Butte and the tract immediately south of Mono Lake, that someone else, working the territory more intensively and listing the critical species statistically (by individual composition, w'hich we did not), might find adequate grounds for mapping it as Upper Sonoran. Returning to the Sierran divide: The Hudsonian Zone is found to be well characterized on the east slope down to an average of about the 9500- foot contour. This zone simply mantles the Sierras, save for the Arctic- Alpine 'islands' which rise above timber line. Below the Hudsonian, good Canadian is represented, with marked resemblance florally to that on the western slope, in the lower part of Bloody Caiion. Moisture conditions are there more exactly as they are on the west flank of the Sierras. Else- where, Canadian is rather different in aspect from what it looks like on the western slope, because of the prevailing aridity. Jeffrey pines and mountain mahogany predominate in the place of red firs and aspens. The steepest declivities, close to the Sierran divide, involve a lowering of altitude to about the 8000-foot contour; thence eaiit to Mono Lake the slopes involved in the long, lateral moraines are gentle, and the blending of Canadian through Transition with 'austral' takes place gradually over several miles of territory. Here is where most trouble wa-s experienced in fixing upon a boundary between Canadian and Transition — and for the same reasons as given above with respect to the Transition-Upper-Sonoran boundary. Good Canadian extends east along the cold streams, where it is marked conspicuously by thickets of aspen, well down toward the shores of Mono Lake — to as low as 7000 feet ; Transition extends west up toward the foot of the east Sierran face, especially along the south-facing slopes of glacial ridges, to 9000 feet. Thus at Walker Lake one finds the interest- ing situation of the Canadian Zone occupying the cool, shaded bed of the glacial groove, with Transition on tiie south, sun-facing Avail above it : the usual zonal relationship is reversed. Pacts such as this strengthen our belief that the prime i)hysical factor accounting for zonation is not altitude, or moisture, or soil, per se, but temperature. DISTRIBUTION OF TEE ANIMALS 11 As is clearly set forth in some of the literature we here cite for perusal by the inquiring reader, the limitation of species on the basis of the life- zone concept is not the only sort of segregation which occurs. Indeed, locally, as in Yosemite Valley proper, often a far more conspicuous manner of delimitation is manifest, the delimitation which takes place on the basis of 'associations.' These minor units involve each a certain type of environment within one zone ; furthermore, closely similar or even identical associations may recur, or be continuous, in two or more adjacent zones. Not rarely, associational restriction seems to be transcendent over zonal restriction, as in the case of the badger, western chipping sparrow, and rock wren. Appropriate discussion of these cases will be found in the chapters (pp. 92, 452, 550) treating of these species. Some of the more important associations of animal with plant or sub- stratum conditions that it has proved useful to recognize in the Yosemite section are as follows, classified by zones. The names chosen are those of some predominating feature, usually of the vegetation. (Consult plates 13 to 19, 36o, and figure 21.) ASSOCIATIONS WITHIN THE LOWEE SONOEAN ZONE Open-water (two types, Eiver and Eose-thicket Slough) Valley-oak Eiparian (Willow-cottonwood) Hog-wallow prairie Marsh Eock outcrop Meadow ASSOCIATIONS WITHIN THE UPPEE SONOEAN ZONE Stream Digger-pine Eiparian (Willow) Blue-oak Meadow Dry grassland Live-oak Eocky-slope Chaparral (two types, Adenostoma and Ceanothus cuneatus) ASSOCIATIONS WITHIN THE TEANSITION ZONE Swift-stream Black-oak Eiparian (two types, Willow-cotton- Golden-oak wood and Alder) Yellow-pine Meadow Silver-fir Dry grassland Boulder-talus Chaparral (two tj^es, Sticky-man- Cliff zanita and Buckthorn) ASSOCIATIONS ON THE AEID EAST SIDE OF THE SIEEEA, IN THE GEEAT BASIN FAUNAE DIVISION OF THE TEANSITION ZONE Alkali-lake Sagebrush Eiparian (Willow) Pinon-juniper Eose-thicket Cercocarpus Shepherdia 12 ANIMAL LIFE IN THE YO SEMITE ASSOCIATIONS WITHIN THE CANADIAN ZONE Swift-stream Bed-fir Biparian (two types, Willow and Lodgepole-pine Comus pubescens) Jeffrey-pine Aspen Granite outcrop Meadow Cliff Chaparral (three types, Bed-cherry, Arctostaphylos patula, and Huckleberry-oak) ASSOCIATIONS WITHIN THE HUDSONIAN ZONE Lake Lodgepole-pine Shore Hemlock Swift-stream Whitebark-pine Biparian (Willow) Talus (or Bock -slide) Meadow Cliff Heather ASSOCIATIONS WITHIN THE AECTIC-ALPINE ZONE Swift-stream Dry grassland Willow-thicket Talus (Bock-slide) Meadow CUff Within each general association there is often plainly to be seen still further restriction in the habitat preferences of species. For example, in the major association, "coniferous forest," in its minor division (within the Canadian Zone) known as the red-fir association, we find several species of birds and of mammals, each adhering closely to a yet smaller division of the general environment. The Sierra Creeper keeps to the larger tree trunks, the Short-tailed Mountain Chickadee to the smaller twiggery, the Western Golden-crowned Kinglet to the terminal leafage, and the Ham- mond Flycatcher to the most prominent twig-ends and the air-spaces between branches and between trees. The Tahoe Chipmunk is largely arboreal, the Allen Chipmunk terrestrial. In final analysis, no two species well established in a region occupy precisely the same ecologic space; each has its own peculiar places for foraging, and for securing safety for itself and for its eggs or young. These ultimate units of occurrence are called "ecologic niches." If two species of the same ecologic predilections are thrown into the same environ- ment, one or the other will quickly disappear through the drastic process we call competitive replacement. Thus it comes to pass that the amplitude of the general environment — the number and extent of distinct ecologic niches it compasses — determines the richness of the fauna, both as regards number of species, and the number of the individuals to the unit of area representing each species. This principle may be abundantly verified by any student who will carry on active field observations a season or two over even a small part of the Yosemite section. 14 ANIMAL LIFE IN THE YO SEMITE Table of Occurrence, According to Life Zone, of the Mammals, Breeding Birds, Reptiles, and Amphibians of the yosemite section Note. — It is intended, in the using of this table, that comparison be made with the life-zone map and profile, plates 61, 62. Width of bar indicates relative abundance of the species concerned; in other words, the widest place in the bar indicates the place, zonally, where the popula- tion is believed to be densest. In case there is some reason to suppose that a species ranges beyond what is shown by the actual facts at hand, such extension is indicated by a broken line. Some of the species which are listed in the present work are omitted from the table because they are non-native, extinct, or of unknown or doubtful status. Water birds are omitted entirely, as are also non-breeding land birds. It must be distinctly understood that this table of zonal distribution is based on our findings in the Yosemite region only ; it must not be inter- preted as setting forth the distributional situation in the Sierra Nevada generally, or in the State at large, though this may approximately be true in the great majority of cases. The zonal diagnoses of species apply primarily to the long, western slope of the Sierra Nevada; many of the species occur only on that side. Exclusively east-side species are so indi- cated by foot-note reference ; and where these latter are known to extend into the Transition Zone from the Upper Sonoran Zone (hence beyond the limits of our section) this fact is indicated by cutting off the bar squarely at the vertical line of demarcation between these two zones. DISTBIBUTION OF THE ANIMALS 15 ^ -5 Yosemite Mole, Scapanus I. sericalus San Joaquin Mole, Scapanus I. campi *Mono Mole, Scapanus I. monoensis Dusky Shrew, Sorex o. obscurus Adorned Shrew, Sorex ornatus Yosemite Shrew, Sorex in. mariposae •Sierra Nevada Shrew, Sorex v. amoenus Navigator Shrew, Neosorex p. naiigator Little California Bat, Myotis c. californicus High Sierra Bat, Myolis I. altipetens Long-legged Bat, Myolis I. longicrus Fringed Bat, Myotis thysanodes Merriam Bat, Pipistrellus h. rr.erriami Large Brown Bat, Eptesicus fuscus Hoary Bat, Nycteris cinerea Pacific Pallid Bat, Antrozous pacificus Mexican Free-tailed Bat, Nyctinomus mexicanus American Black Bear, Ursus americanus Mountain Coyote, Cam's I. testes Cascade Red Fox, Vulpes cascadensis San Joaquin Kit Fox, Vulpes m. rr.ulica California Gray Fox, Urocyon c. californicus California Ring-tailed Cat, Bassariscus a. raptor California Coon, Procyon I. psora Sierra Pine Marten, Martes c. sierrae Pacific Fisher, Martes p. pacifica Sierra Nevada Wolverine, Gulo I. luleus Mountain Weasel, Mustela arizonensis Sierra Least Weasel, Mustela muricus Pacific Mink, Mustela v. energumenos California Spotted Skunk, Spilogale p. phenax Striped Skunk, Mephitis occidenialis California Badger, Taxidea I. neglecla Northwestern Mountain Lion, Felis o. oregonensis California Wildcat, Lynx e. californicus Gambel White-footed Mouse, Perotnyscus m. gambeli *Sonora White-footed Mouse, Peromyscus m. sonoriensis Boyle White-footed Mouse, Peromyscus b. boylii Gilbert White-footed Mouse, Peromyscus t. gilberti * On east side of Sierras only. 16 ANIMAL LIFE IX THE YO SEMITE 3 (2 ^ I a. S True White-footed Mouse, Peromyscus I. truei Parasitic White-footed Mouse, Peromyacus c. catifomiau •Short -tailed Grasshopper Mouse, Onychomys I. brevicaudua Long-tailed Harvest Mouse, ReithrodorUomys m. longicauda Strcator Wood Rat, \eolomaf sireatori Gray Bushy-tailed Wood Rat, Neotoma c. cinerea Yosemite Meadow Mouse, Microlus m. yosemite Tule Meadow Mouse, MtcrotU3 c. acstuarinua Mariposa Meadow Mouse, Microtus c. mdriposae Sierra Cantankerous Meadow Mouse, Microtus m. sierrae "Short-tailed Meadow Mouse, Lagurus curtatus Mountain Lemming Mouse, Phenacomys orophilus Fresno Pocket Gopher, Thomomys b. pascalis Digger Pine Pocket Gopher, Thomomys b. meua Yosemite Pocket Gopher, Thomomys a. au-ahnee Sierra Nevada Pocket Gopher, Thomomys m. monlicola •Fisher Pocket Gopher, Thomomys q fisheri Cahfornia Pocket Mouse, Perognuthus c californicus San Joaquin Pocket Mouse, PerognaOnts i inornalus 'Great Basin Pocket Mouse, Perognuthus p oliiaceus Heermann Kangaroo Rat, Dipodomys h. heemtanni Merced Kangaroo Rat, Dipodomys h dizoni •Pale-faced Kangaroo Rat, Dipodomys teucogenys •Mono Kangaroo Mouse, Microdipodops polionotus Allen Jumping Mouse, Zapus p attcni Yellow-haired Porcupine, Erethizon e. epixanthum Sierra Mountain Beaver, Aplodontia r califomica Southern Sierra Marmot, Marmota f sierrae California Ground Squirrel, Citcltus b becchcyt Bclding Ground Squirrel, Cittllus beldingi •Stephens Soft-haired Ground Squirrel, Citellus m. stephensi Sierra Nevada Golden-mantled Ground Squirrel Callospermuphilus c. chrysodeirus Tahoe Chipmunk, Eulamias s frater Allen Chipmunk, Eulamias senez Mariposa Chipmunk, Eulamias m. mariposae Long-eared Chipmunk, Eulamias quadrimaculalus Alpine Chipmunk, Eulamias alpittua •Mono Chipmunk, Eulamias a. monoensia •Sage brush Chipmunk, Eulamias jrictua • On east side of Sierras only. DISTBIBUTION OF THE ANIMALS 17 S 2 California Gray Squirrel, Sciurus g. griseus Sierra Chickaree, Sciurus d. albolimbatus Sierra Flying Squirrel, Glaucomys s. lascimis Golden Beaver, Castor c. subauratus Yosemite Cony, Ochotona s. muiri California Jack Rabbit, Lepus c. califomicus *Desert Jack Rabbit, Lepus c. deserlicola Sierra White-tailed Jack Rabbit, Lepus I. sierrae Sacramento Cottontail, Sylirilagus a. aTuiubonii Washington Cottontail, Syhnlagus n. nuUaUii Mariposa Brush Rabbit, Sylvilagus b. mariposae Mule Deer, Odocoileus h. hemionus Mountain Quail, Oreortyx p. plumijera Valley Quail, Lophortyx c. vallicola Sierra Grouse, Dendragapus o. sierrae *Sage-hen, Centrocercus urophasianus Band-tailed Pigeon, Columba f. fasciata Western Mourning Dove, Zenaidura m. marginetla Turkey \'ulture, Calhartes a. septentrionalis Sharp-shinned Hawk, Accipiter velox Cooper Hawk, Accipiter cooperi Western Goshawk, Astur a. striatulus Western Red-tailed Hawk, Buteo b. calurus Red-bellied Hawk, Buteo I. elegans Swainson Hawk, Bvteo sumnsoni Golden Eagle, Aquila chrysaetos American Sparrow Hawk, Fako s. sparverius Barn Owl, Tyto pratincola Long-eared Owl, Asia vnlsonianus California Spotted Owl, Strix o. occidentalis Great Gray Owl, Scotiaptex n. nebulosa Saw-whet Owl, Cryptoglaux acadica Southern California Screech Owl, Otus a. quercinus Pacific Homed Owl, Bubo v. pacificus Burrowing Owl, Speotyto c. hypogaea CaUfomia Pigmy Owl, Glaucidium g. califomicum Road-runner, Geococcyx califomianus Western Belted Kingfisher, Ceryle a. caurina Modoc Woodpecker, Dryobates v. orius * On east side of Sierras only. 18 ANIMAL LIFE IN THE TOSEMITE Willow Woodpecker, Dryobalcs p. turati Nuttall Woodpecker, Dryohata nuttalli T9? Northern White-headed Woodpecker, Xenopicui a. albohn'alu Arctic Three-toed Woodpecker, Picoidea arclicus Sierra Red-breasted Sapsucker, Sphyrapicus v. daggelli Williamson Sapsucker, Sphyrapicus t. thyroideus Northern Pileatod Woodpecker, Phloeolotnus p. abieticola California Woodpecker, Melanerpesf. bairdi Red-shafted Flicker, Colaptes c collaris Dusky Poor-will, Phalaenoptilus n. califomicus •Nuttall Poor-will, Phalaenoptilm n. nuttalli Pacific Nighthawk, Chordeiles v. hesperis Texas Nighthawk, Chordeiles a. teiensis Northern Blade Swift, Cypseloides n. borealis White-throated Swift, Aeronauies melanoleucits Black-chinned Hummingbird, Architochus alexaruiri Anna Hummingbird, Calypte anna Calliope Hummingbird, Stellula calliope Western Kingbird, Tyrannus verticalis Ash-throated Flycatcher, Myiarchus c. cinerascens Black Phoebe, Sayornis nigricans Olive-sided Flycatcher, Nuttallornis borealis Western Wood Pewec, Myiochanes r richardswti Wright Flycatcher, Empidonax urighli Hammond Flycatcher, 'Empidonax haminondi Traill I'ly catcher, Empidonax t. traiili Western Flycatcher, Empidonax d. difficili: •Gray Flycatcher, Empidonax griscus California Horned Lark, Olocoris a. aclin •Black-billed Magpie, Pica p. hudsonia Blue-fronted Jay, Cyanocitta s. frontalis Interior California Jay, Aphelocoma c. immanis •Woodhouse Jay, Aphelocoma woodhousei Clark Nutcracker, Nucifraga columbiana •Pifion Jay, Cyanocephalus cyanocephalus Dwarf C'owbird, Molothrus a. obscurut •Nevada Cowbiid, Molothrus a. arlemisiae Bi-colored Red- winged Blackbird, Agelaius p. califomicus •Nevada Red-winged Blackbird, Agelaius p. netxtdentii • On east side of Sierras only. DISTRIBUTION OF TEE ANIMALS 19 ^ ^ Kern Red-winged Blackbird, Agelaius p. aciculalus Tri-colored Blackbird, Agelaius tricolor Western Meadowlark, Stumella neglecta Bullock Oriole, Icterus bullocki Brewer Blackbird, Euphagus cyanocepfialus California Evening Grosbeak, Hesperiphona v. califomica California Pine Grosbeak, Pinicola e. califomica California Purple Finch, Carpodacus p. califomicus Cassin Purple Finch, Carpodacus cassini California Linnet, Carpodacus m. frontalis Sierra Nevada Rosy Finch, Leucoslicte t. dawsoni Willow Goldfinch, AstragalinTis t. salicamans Green-backed Goldfinch, Astragalinus p. hesperophilus Lawrence Goldfinch, Astragalinus lawrencei Pine Siskin, Spinus p. pinus •Western Vesper Sparrow, Pooecetes g. confinis 'Nevada Savannah Sparrow, Passerculus s. nevadensis Western Grasshopper Sparrow, Ammodramus s. bimaculalus Western Lark Sparrow, Chondestes g slrigatus Hudsonian White-crowned Sparrow, Zonotrichia I. leucophrys Western Chipping Sparrow, Spizella p arizonae *Brewer Sparrow, Spizella breweri Sierra Junco, Junco o. thurberi Bell Sparrow, Amphispiza belli *Nevada Sage Sparrow, Amphispiza n. nevadensis Rufous-crowned Sparrow, Aimophila r. ruficeps *Modoc Song Sparrow, Melospiza m. jisherella Northeastern Lincoln Sparrow, Melospiza I. lincolni Mariposa Fox Sparrow, Passerella i.. mariposae •Mono Fox Sparrow, Passerella i. morwensis Sacramento Spurred Towhee, Pipilo m. falcinellus •Nevada Spurred Towhee, Pipilo m. curtatus Northern Brown Towhee, Pipilo c. carolae Green-tailed Towhee, Oberholseria chlorura Pacific Black-headed Grosbeak, Zamelodia m. capilalis California Blue Grosbeak, Guiraca c. salicarius Lazuli Bunting, Passerina amoena Western Tanager, Piranga ludoviciana Cliff Swallow, Petrochelidon I. lunifrons * On east side of Sierras only. 20 ANIMAL LIFE IX THE YOSEMITE * On caal side of Sierras only DISTRIBUTION OF THE ANIMALS 21 Western Golden-crowned Kinglet, Regulus s. olivaceus t ° .3 -s ^ -5 Western Ruby-crowned Kinglet, Regulus c. cineraceus Western Gnatcatcher, Polioptila c. obscura Townsend Solitaire, Myadestes Unimsendi Russet-backed Thrush, Hytocichla u. ustutata Sierra Hermit Thrush, Hylocichla g. sequoiensis Western Robin, Planesticus m. propinquus Western Bluebird, Sialia m. occi'dentalis Mountain Bluebird, Sialia currucoides Western Fence Lizard, Sceloporus o. occidentalis •Pacific Blue-bellied Lizard, Sceloporus o bi-seriatus Tenaya Blue-bellied Lizard, Sceloporus o. iaylori Mountain Lizard, Sceloporus g gradosus California Horned Toad, Phrynosoma b. fronlale San Diego Alligator Lizard, Gerrhonotus s. uebbii Sierra Alligator Lizard, Gerrhonotus palmeri California Whip-tailed Lizard, Ctiemidophorus t. mundus Western Skiiik, Plesliodon skillonianus Rubber Snake, Charina bottae Pacific Garter Snake, Thamnophis s. infemalis Mountain Garter Snake, Thamnophis o. elegans Western Ring-necked Snake, Diadophis a. amabilis Coral King Snake, Lampropellis multicincta Boyle King Snake, Lampropellis g. boylii California Striped Racer, Coluber lateralis Valley Gopher Snake, Pituophis c. heermanni Pacific Rattlesnake, Crolalus oreganus Pacific Mud Turtle, Clemmys marmorata Pacific Coast Newt, N olophthahnus torosus Mount Lyell Salamander, Eurycea platycephala Arboreal Salamander, Aneides I. lugubris Slender Salamander, Batrachoseps attenuatus •Western Spade-foot Toad, Scaphiopus h. hammondii California Toad, Bufo b halophilus Yosemite Toad, Bufo canorus Pacific Tree-toad, Hyla regilla California Yellow-legged Frog, Rana b boylii Sierra Yellow-legged Frog, Rana b sierrae California Red-legged Frog, Rana a. draytonii * On east side of Sierras only 22 ANIMAL LIFE IN THE YO SEMITE CENSUSES OF BIRDS IN THE YOSEMITE SECTION To convey an adequate idea of the bird life of any given area, enumer- ations of species are not alone sufficient; the numbers of indivkluals of each species must also in some way be indicated. The usual terms ' ' abundant, ' ' "common," "rare," and the like, are unsatisfactory in that their meaning varies both with the person employing them and with the kinds of birds considered. In the latter regard, the Western Chipping Sparrow and the Western Red-tailed Hawk might both be put down as ' ' common, ' ' whereas the sparrow may have been observed in actual numbers ten times those of the hawk. Counts of individual birds are fairly practicable when made in the breeding season on the basis of some unit of area such as an acre. At that season each adult pair is settled within a particular circumscribed locality, and the male is in song. But as soon as the young are out, and from then on throughout the year until the beginning of the next nesting season, most species of birds are moving about incessantly. Counts of individuals are then very difficult to make and furthermore are likely to be misleading because of their great variation in any small area from hour to hour and from day to day. And so, in our field work in the Yosemite region, we put into effect the following different method. Instead of using a unit of area, we used a unit of time. Birds were listed, as to species and individuals, per hour of observation. In a general way this record involved area, too. Our censuses were practically all made on foot, and the distance to the right or left at which the observer could see or hear birds did not differ, materially, in different regions. The rate of the observer 's travel did, of course, vary some ; for example, when climbing a steep trail, or going through chaparral, progress was slower than when hiking straightaway along open ridges. Also, in some places, the greater density of the vegetational cover acted to limit the range of sight. But for each of these adverse features of the method there were certain compensations. For recording a census, a piece of cardboard and a pencil wore carried, the names of the various species of birds jolted down, and their numbers checked, as they came to notice. The presence of no species was assumed ; but probabilities were given consideration in making identifications. In cases where birds were seen or heard, but their identity was not established with certainty, provisional names were entered, each followed by a question CENSUSES OF BIBDS 23 MUSEUM OF VERTEBRATE ZC Date.(A£>;iJ.^S'.y\m(^ )OLOGY Nature of route (2 Wcarter.C^&C/lvt one, /aun( CENSUS SHEET 1, assodaKon$)JiaA!4iii9>i. Observer ,CiO- > f2^^-2 4-0 30 f^.^is f.M, Totals BluA- KovubJcJoM / / O tatrtA vUAtto 5 £ G /3 dtuiuJ^ IOcxaM^ /(? 3 /:3 ^ulpA'CnGUIYUid lOMqjljdt (0 1 7 rUrwn £ V 6 (J 0/1.6^ ^ 7 3 /V C^laoiM/i opaMcpO / 2 ^ iT lAikvi e 1 1 ^ Ofii0 (xy/2/ ^± 1 3± VflGU/iUJlu/y\ (%JucM.Q.AjiL> 1 1 Z Gleiuia C>ijLaja£lv ^ Z 1 5" G-o^cte/yi-C/i6wywri( KIm.M' ^, -^ 1 6 lUedt (Jflt/J^^a /mo 3 Z ^ 7 CoAGvy, VubLo 3 Z 3 S C^. H LdlUo U)cuii^ ,=? 1 1 .5- (^jA ^ boA^ 1 / (Bidtfe-cl KOvt«y^cc^?uLa t / (6r.oi^f€/i/ €iU«A^rW;( 9 3 (Bfloui- ^QjoMA GAxxJkil. 1 1 U^iMcrvo U)frT>7^QaoW; 1 1 lRii.-si»va|tri 'PUkw 1 1 (BoMcl- i"acfieO( Ptcii2xm ICt)+ \00+ ?r(Mi;A>\.aA\ tOAfiyvl 1? 1 r TOTALS (hourly and grand) H8 3Z IZ^f ZOS* Fig. 3. A sample census sheet. 24 AMMAL LIFE IS THE YOSEMITE mark. Occasionally the bird could be identified only a-s to its general grouping, as "hawk." Species of very close resemblance were sometimes grouped together in a joint entry; for example, the crowned sparrows (Zonotrichia). The plus sign indicated that more were present than the actual number entered : the birds could not be counted with certainty ; flocking birds, for instance, frequently could not be counted accurately. At the close of the day or of the period of observation, we were accus- tomed to transfer our censuses from the field sheet (more or less scribi)led. in lead pencil) to our permanent notebooks. If but few species of birds had been seen, these were entered seriatim with numbers of each observed, and comments ; if a goodly census had been secured we entered the results in more formal, tabular style, on special sheets printed for this pur- pose (fig, 3). In either case, record was kept of exact time involved, approximate distance covered, nature of territory traversed, and weather conditions. Totals were computed, both of species and individuals. Comparisons of these totals for different parts of the Yosemite region and for different seasons have brought forth some interesting conclusions. Outstanding among these generalizations are the following: The greatest bird popu- lation, both summer and winter, is found in the Upper Sonoran Zone. Next come the Lower Sonoran and Canadian zones. The Transition Zone ha-s a fairly large population in summer, but its population drops far down in winter. The Hudsonian has the sparsest summer population, except, of course, for the Alpine-Arctic. The winter population below the snow line consists more largely of seed and berry eaters than of insect feeders ; the summer population everywhere contains a predominating proportion of insect-eating birds. "We present below a series of censuses, selected from the more than 250 in our notebooks. The censuses given are chosen to illustrate, first, the nature of the avifauna in various representative parts of the Yosemite section, and, second, the marked changes in bird life taking place in Yosemite Valley from season to season through the year. The series of censuses given for Yosemite Valley is more complete than for any other station in the section. It begins at the height of the nesting season with two censuses on se])arate days in two different parts of the Valley, embracing widely different sorts of habitats (associations) an. It visits isolated or BEAB8 67 unguarded camps and purloins hams, bacon, canned goods and fruits, raids garbage cans, and digs up heaps of tin cans and other kitchen refuse buried by campers. A considerable number of the bears living in Yosemite Valley regularly forage at the garbage pits and incinerators in the vicinity of Cathedral Spires, as many as 10 and even 15 having been seen there by attendants, usually at late dusk. Tin cans are nosed over and thoroughly cleaned of any remaining particles of their original contents, and melon rinds and other vegetable materials are readily devoured. Peach, plum, and olive pits, watermelon, muskmelon, and apple seeds, lemon rinds, eggshells, bones of chickens, mammal hair, and bones from various cuts of meat are among the objects we found to have been devoured by these bears. Even papers which have been wrapped around butter and cured meats are eaten for the grease and salt which they have absorbed. At the storehouse of the construction camp in Hetch Hetchy Valley, in the winter of 1915-16, bears ripped 2-by-12-inch planks off the window openings, clambered in, and made way with hams, bacon, and canned goods, even while lights were burning in the house and persons were present in other portions of the building. As regards the relation of Black Bears to stock, Mr. George Smith of Jamestown, Tuolumne County, has told us that in the seventies it was necessary to 'thin out' the bear population before sheep could be run with safety in the mountains. At that time almost every meadow had its bear trap or pen, a small log house of stout construction with a heavy door so arranged that when a bear entered and seized the bait the door would fall and the animal would be imprisoned. Some of these traps may still be seen on meadows in the northern part of the Park. Horses readily take fright at the sight of a bear, although we know of no case in which a bear has actually attacked a horse. In Hetch Hetchy Valley Mr. C. C. Bull has told us of bears visiting hog pens and feeding in the troughs alongside of the rightful partakers without molesting or disturbing the latter. Mr. John L. McLean has told us that bears come down around his ranch on Smith Creek (6 miles east of Coulterville) to feed on acorns, but that they have never molested either poultry or stock. However, he knew of one occasion when some pigs were taken by Black Bears on Bullion Mountain. Finally in regard to persons: We know of but two instances in which a Black Bear has even attempted to molest any human being in the Park. One case, of a mother bear resenting disturbance of her young, is recounted in the chapter on the Grizzly Bear. The second instance is as follows. Mr. George Smith states that while cruising timber in the Tuolumne basin a number of years ago he was chased down-hill by a she-bear. He distracted the attention of the animal by picking up stones and pieces 68 ANIMAL LIFE IN THE YO SEMITE of wood and throwing them to one side or another as he ran. Finally he jumped upon and ran along a fallen tree trunk and dropped into a willow thicket at the base of the log. The bear, evidently losing the trail, thereupon gave up the chase. Mr. Gabriel Souvelewsky relates that while traveling along the south wall of the Tuolumne Cafion late one afternoon he came to a rock ledge occupied by two cinnamon bears. One of these growled and made threatening advances so that Mr. Souvelewsky thought it best not to continue farther in their direction. But he wa.s not actually pursued. The female mentioned above as being seen by the junior author near Camp Curry in June, 1910, even though accompanied by her cubs, was not unduly resentful of human intrusion. Several persons were taking pictures of her while she had her cubs in sight, and later, when she had hidden them, she came down and fed at a garbage heap while some forty people looked on and snapped pictures at as short a distance as twenty feet. Grizzly Bear. Ursus henshawi Merriam The history of the Grizzly Bear in the Yosemite region and indeed throughout California is evidently a closed chapter in the book of nature. In the "days of '49" numbers of the big fellows roamed over the hills and valleys of California, and the Yosemite region doubtless had its full quota of them. But the presence of the Grizzlies was incompatible with the interests of the white man, and so they were killed off rapidly, until now it seems likely that they are entirely gone. So sudden was their extermination that no complete specimens were secured to be preserved in our museums. And reliable accounts, published or in manuscript, of the California grizzlies are meager at best. The word Yosemite^ is derived from a word in the tribal dialect of the southern Miwok Indians who inhabited the Valley when it was discovered by white men. This word, Uzumati, or Uzhumati, means grizzly bear, a full-grown animal rather than a cub. The use of this name in as.sociation with the Valley might be taken as an indication that Grizzly Bears orig- inally inhabited the Yosemite Valley. But we have no precise evidence to show that such was the case. Early visitors to the Yosemite often mention "grizzlies" and "bears" in their narratives, but with an am- biguity that leaves the reader uncertain as to whether a veritable Grizzly was encountered anywhere in the Valley proper. The names Bear Valley, Bear Creek, Big Grizzly Flat, and Little Grizzly attest the former wide occurrence of Grizzly Bears in the foothill district of the region. 8 For the circumstances Burrounding the choice of the nanio consult L. H. Bunnell, Discovery of the Ynxrmite; for diFCUFsion of tho nionning of the word see paper by A. L. Kroebcr, (^.-iliforiiia Place Names of Indian Orijrin (Univ. Calif. Publ. Am. Arch. Ethn., vol. 12 [1916], p. 68). BEAES 69 The Grizzly Bears as a group (including several species and races) are quite distinct from the Black Bears. The size of adults was generally much larger, though the species which occurred in the Yosemite region was one of the smaller of the grizzlies. No weights or detailed measurements of locally captured grizzles are preserved. The "nose to tail" measurement of "nearly 10 feet" given by its captor for the Wellman specimen referred to below, applied to a skin as pegged out fresh. It is well known that considerable stretching results from such procedure, and that when the skin is relaxed and tanned it shrinks somew^hat. The length of the Wellman grizzly skin is now 71/2 feet and its width at the middle is 5 feet. Judging from the dimensions of bears before skinning, in known cases, as compared with those of the tanned skins measured subsequently, the Wellman bear in the flesh probably measured between 6I/2 and 7 feet in length, tip of nose to tip of tail. The Washburn skin mentioned later measures 6 feet 7 inches in length, somewhat smaller ; and the living animal was therefore probably close to 6 feet long. The foreclaws of the Grizzly are much less sharply curved and some- what longer than those of the Black Bear; this is an absolutely distinctive character. The longest claws on the AVellman skin are 3 inches (measuring the chord of the claw from tip to upper base), while the middle fore- claw of a large California-taken Black Bear is only 2 inches in the same dimension. The track of an old Grizzly, either front or hind foot, was much larger than that of a Black Bear. Wellman 's figures, 10 by 13 inches, and McLean's, 9 by 17 inches (even allowing for considerable sliding of the foot, especially in the latter case) are 50 per cent larger in each dimen- sion than the track of a good-sized Black Bear. These measurements of course refer to the hind foot, which is decidedly longer than the forefoot. The latter (if the 'wrist' does not touch) leaves an imprint that is more nearly square in outline. In coloration the Grizzly was dark brown, and some individuals had grayish or whitish ends to the longer guard-hairs on the back, which gave rise to the name ' ' silver-tip. ' ' The Grizzly differed from the Black Bear in habits as well as in struc- ture. It was, particularly in the case of the Henshaw Grizzly, a frequenter of chaparral (and hence essentially an inhabitant of the foothill districts), and it never (or rarely) climbed trees. Its food, as with the Black Bear, was quite varied, including berries, fruits, and insects, as well as flesh; but the Grizzly worked much more havoc among large game, and in later years, stock, than does its smaller relative. During our work in the western part of the Yosemite section we questioned numerous old residents concerning the former occurrence of Grizzly Bears, but rarely obtained definite information. Mr. J. B. Varain, of Pleasant Valley (= Varain), told us that there were no Grizzlies there 70 ANIMAL LIFE IN THE YOSEMITE when he arrived in 1867, but that they were then still to be found in the territory to the east. The various gold rushes to Tioga and Mammoth, together with the running of sheep and other stock in the region, served to clear the Yosemite country of its Grizzlies at a relatively early date. The occurrence of the one taken in 1887, by Wellman, was by that year considered an unusual event. We were unable to get track of even a fragment of a specimen of the Grizzly in the narrow section which we worked across the Sierras; but since our field work was completed, there have come to light two skins of Grizzlies killed elsewhere within the present boundaries of Yosemite National Park. Both of these skins are now in the Museum of Vertebrate Zoology of the University of California. One of these bears (obtained from IMrs. John S. Washburn) is the last known to have been killed in the region. It was shot "about 1895" at Crescent Lake, which lies some ten miles air-line east of Wawona at an altitude of 8500 feet. It is possible that a few individuals persisted in the same region until a considerably later date. This surmise is strengthened by the following account. Mr. John L. McLean and his son Donald have told us that during the fall and winter months from 1908 until 1911 a very large bear lived on Bullion Mountain. The tracks, which were examined on two or more occasions in two successive years, "were 9 by 17 inches (or a little more) by actual measurement." The animal had long claws, as shown by the tracks. The bear had five separate trails leading up the side of the moun- tain from the heavj' chaparral (composed of Adenostoma and scrub or "vine" oak) on the lower slopes, to the black and blue oaks on the top. The dung indicated that the bear was living principally upon acorns. There were wild hogs on the mountain and these may have been an attrac- tion to the big bear. The smaller (Black) bears seemingly had little or nothing to do with the big fellow, avoiding his trails and staying off in another canon. A trap was once set for the big bear, and caught him ; but he pulled loose "at one jump." Finally a party of men with dogs got after the big bear and it "left the country," without being injured, and was not seen again. Small bears are still present in the region. The circumstances surrounding the killing of the "Wellman bear" have been set down at considerable length in a letter written by one of the principals, Mr. Robert S. Wellman, under date of April 20, 1918. This letter is now on file at the Museum of Vertebrate Zoology, and from it we take the following. Mr. Wellman 's headquarters were, at that time, at Buck Caniii, sonit> 16 miles east of Wawona, near the South Fork of the Merced River. On the evening of October 17, 1887, at the head of a small valley about a mile away from the camp, he discovered the carcass of a cow on which bears BEARS 71 had already commenced to feed. A search of the vicinity disclosed the presence of a female Black Bear and three cubs. The next morning Mr. Wellman visited the place again and found that during the night a larger bear had come and dragged the carcass several yards from where it first lay. Being certain that this new arrival was a veritable Grizzly he rode over to the camp of his friend Jim Duncan,* now long deceased, and got him to come over to help in the hunt. The two men built a scaffold, or platform, 10 feet above the ground and some 60 feet from the dead cow. And on this platform watch was kept for the succeeding three nights. One or more black bears and a coyote came to feed, but it was not until the third night that the big bear put in its appearance again. When it did, it happened that three small bears were at the carcass; but these quickly quit the vicinity when the large bear appeared. Finally, the Grizzly caught sight of the scaffold, and made toward it. The two men fired simultaneously and the bear fell to earth with a series of 'bawls,' evidently wounded. The men did not come down until daylight, when the animal was found in some bushes and killed by a shot behind the ear. The skin of this bear was sold by Mr. Wellman to the artist, Thomas Hill, and, through the latter 's son-in-law, was procured in 1918 for the University of California. Mountain Coyote. Canis latrans lestes Merriam^ Field characters. — General appearance that of a large collie dog (pi. 39a) ; head and body about 30 to 33 inches long, tail with hairs 12 to 15 inches; ears pointed, about 414 inches (114 mm.) high, habitually carried erect. General coloration gray, or grayish 4 This is in all probability the same Duncan mentioned by John Muir in the chapter on "The Animals of the Yosemite" in his book, Our National Parks (see Bibliography, p. 667). Muir relates that Duncan, who had quite a reputation locally as a bear hunter, had a cabin on the shore of Crescent Lake. In nine years he had killed no less than 49 bears [probably both Black and Grizzly]. He kept count of his killings by "notches cut on one of the timbers of his cabin. ' ' Crescent Lake is but a short distance from Buck Camp, and Duncan was doubtless living there in 1887 when Wellman went to get his assistance. 5 Our series of specimens, skins and skulls, from the Yos.emite region, serve to demon- strate beyond much doubt that two races of ' mountain ' coyote are represented, a high mountain and Great Basin form, and a foothill form. The Park rangers, and trappers generally, recognize the two, often distinguishing the larger, stouter, and more grayish colored animal under the name ' ' gray wolf. ' ' This is certainly the Canis latrans lestes Merriam. The foothill animal, ranging down the west slope of the Sierras from about the 6000-foot contour nearly to the edge of the San Joaquin Valley, differs from lestes proper, in being of smaller average size, in having brighter color (more reddish) and a lighter built skull, and in certain other cranial characters. The relationship of this foothill form is clearly close to lestes, under which name we place it. Some of the specimens at hand from both El Portal and Yosemite Valley are intermediate in char- acter, indicating that there had been free interbreeding of the animals at about the level where their respective ranges meet. There is likelihood that a third kind, the Valley Coyote, Canis ochropus ochropus Eschscholtz, also occurs in the Yosemite section, at its extreme western end, about Snelling. Unfortunately, we obtained no specimens of coyote out on the plains. This coyote of the open San Joaquin Valley is sharply distinct from either of the races of the Mountain Coyote by reason of its coarser, less furry coat, which is of a light reddish rather than either deep reddish or grayish cast of color. It has much larger ears, a longer slenderer snout, and smaller teeth. 72 AMMAL LIFE IX THE Y OH EMIT E brown, with black along back, and with reddish brown of varj'ing tone on nose, ears, back, and legs. Tail very bushy, 4 or more inches in diameter, black tipped. Tracks: Dog like, longer than wide, in a large animal 2% by 2% inches (6 by 7 cm.) ; impression of heel pad but little larger than that of any individual toe; claw marks not always showing. Droppings: Dog-like, about % inch in diameter. Voice: A loud, moderately high-i)itched barking, interspersed with shrill waitings, usually continued for several seconds; rarely heard except during the night. Occurrence. — Moderately common almost throughout the Yosemite section, from the westernmost foothills eastward across the Sierran crest to the Mono Lake district. In winter some of the high mountain individuals descend to lower altitudes, and range down on the west slope to at least the 3500 foot contour, as at Cascades. In Yosemite Valley the animal is most often seen or heard in fall and winter. Frequents various sorts of country; often seen in the open. Usually seen singly. In spite of the great amount of trapping and hunting carried on against them for many years, coyotes remain fairly common in the Yosemite section. Summer travelers, especially in the territory above the level,^of Yo.semite Valley, are likely to catch sight of the animals or, if not so fortunate, at least to see their tracks or hear their howling. At almost every camp which we made in the region we ourselves were apprized of the presence of the animals in one or another of these ways. The coj'Ote is not easily to be confused with any other wild mammal. It resembles in general appearance some of the domestic breeds of dogs, especially the collie and the 'wolf dogs,' yet offers decided points of differ- ence. The body of the coyote is high and narrow (compressed), the face and snout long and tapering (pi. 39a), the ears high (4 inches or more in an adult) and habituallj' carried erect, the tail moderately long, round, and bushy, the feet smaller than in a dog of the same bulk, and the legs slenderer and relatively long, the body being carried well above the ground. From all of the fo.xes the coyote differs in ils much larger size and in its relativel}^ longer legs. From the California Valley Coyote, which lives on the San Joaquin plains, the Mountain Coyote is distinguished by larger size, stouter build, greater weight of body, and heavier fur. In tone of color some of the high mountain individuals are so much paler than the footliill and valley animals as to give rise to the local term "gray wolf." An average adult Mountain Coyote measures about 45 inches from tip of nose to tip of tail. The tail is about 13 inches long. The height of the animal at the shoulder is about 20 inches. The weight of a male is in the neighborhood of 25 pounds. Some will exceed this weiglit, while many of the animals which are trapped in late fall, that is, the young of the year, will weigh considerably less. Females are somewhat smaller ;ind of lighter weight than males of a corresponding age. The pelage of the Mountain Coyote is heavy all thro\igh tlie year, bi'ing always denser and 'woollier' than that of the Valley species at the same season. In the coat of the Mountain Coyote there ai-e relatively few of llie COYOTE 73 coarse overhairs or 'guard hairs' while there is proportionately more of the fine under-fur. The reverse is the case in the Valley Coyote. In other words, the Mountain Coyote is a 'woolly' animal; while the Valley species is ' hairy. ' A thick coat of fur to protect it from cold is of course essential for an animal which dwells during the winter months in snow-covered mountains. The coat of the Mountain Coyote is probably subjected to relatively slight wear, because the animal lives more in the open and has its den among rocks rather than in a burrow in the ground. Its tail never loses its rounded 'bottle-brush' form. One molt occurs each year, in the fall, taking place some time between September and December. The transition from the old hair and fur to the new does not bring about nearly so great a change in appearance in this species as it does in the Valley Coyote. Just after the molt is completed, when all the old hair has fallen out and all of the new is fully grown in, the fur is prime, from the stand- point of the trapper and fur dealer. The wear which does occur in the Mountain Coyote, even though slight, results in lightening the coat color; some of the black hair tippings are lost and at the same time the reddish tones pale out, so that the general gray tone becomes even more pronounced. With the coming of autumn, many of the small mammals at the higher elevations go into hibernation and, with the arrival of the snow, the retreats and forage grounds of others are covered over. The Mountain Coyotes, which have lived well all summer, are now forced to hunt more assiduously for food. The migratory tendency which results in the appear- ance of some of the big gray coyotes at the lower altitudes on the west side of the mountains may well be a result of this stress. In October, the numbers of coyotes in Yosemite Valley are augmented, and from then on the animals are more or less common in the environs of the Valley between the altitudes of 3500 and 7000 feet. The high-zone animals probably never go lower than is necessary to find an adequate supply of food. In Yosemite they keep to the north side of the Valley about Mirror Lake and in the taluses near Rocky Point, Yosemite Falls, and Indian Cailon, where favor- able den sites abound, and whence they can sally forth at night to search the meadows for mice and gophers, the houseyards for chickens, or the garbage pits for table scraps. The Mountain Coyote ranges upward regularly to above timber line. On July 17, 1915, tracks of a Mountain Coyote were seen in Donohue Pass, altitude 11,100 feet, near Mount Lyell. This is our highest station for the occurrence of the species. This animal had crossed the 'pot-marked' snow- field, stepping carefully on the edges of the 'riffles,' seldom dropping into the holes. The track of a coyote cannot be distinguished surely from that of a large dog, but as dogs are not allowed in Yosemite National Park, save 74 AMMAL LIFE J\ THE YOSEMITE when they are occasionally used by rangers, little chance of confusion on that score is likelj^ to arise. The four toes and one heel pad each make an impression, that of the heel being only slightly the larger. On soft ground or snow, into which the feet can sink, the claws, also, leave imprints. The foot impression as a whole is longer than broad, that of a large animal in soft snow mea.suring 80 by 70 millimeters. The Mountain Lion track is much larger, and proportionately wider, the heel imprint is much wider, and no claw marks ever show. The wolverine's track shows five unequal toes and a very large triangular heel pad. The tracks of all the other mountain carnivores (bears of course excepted) are mueii smaller than those of the Mountain Coyote. The coyote's foot is so constructed as to give the animal, in spite of its weight and size, a decided advantage when traveling over snow. The toes spread somewhat, thus giving an expanded area of support. The coyote is thereby enabled to run over relatively soft and deep snow, where a deer would break through and make, at best, only slow progress. The gait of a Mountain Coyote resembles in certain respects that of a dog. Undisturbed, the animal walks or trots. "When stalking prey, such as a mouse or gopher, in the open, it proceeds very slowly and with caution. Its best gait for making distance is a gallop, which is easier than the gallop of most dogs. The speed at which a frightened coyote can lope away is surprising to anybody observing one for the first time. The animal now and then casts a crafty glance to one side or the other but this in no degree lessens the rate of its departure. We did not ourselves catch sight of more than a single coyote at any one time. Ranger Townsley reports seeing two together on one occasion. We have no definite knowledge of the animals occurring in larger groups at any time, in spite of rumors that they some- times "hunt in packs." The Mountain Coyote as compared with the Valley species is thought to be of bolder disposition; and it is much more of a hunter of tiie larger active sorts of prey. The Mountain Coyote seems to prefer to get its prey through capture in the open or by digging it out. It is less of a carrion feeder. It is not at all averse, however, to eating carrion. It will feed on the carcass of a deer long dead; and we have captured coyotes in trajis baited with the partly decayed bodies of small mammals and l)ir(ls dis- carded days before in the preparation of specimens. On July 25, 1920, at the Dudley ranch, 6 miles east of (%ndlerville. Mr. Donald D. McLean liad ;ni cxerplioual opportunity to sei' a coyote in action. Mr. McLean had taken his position at daylight on top of one of the barns. Considerably before suin-isc a coyote suddenly appeared close to the house and snapped up one of a flock of chickens that had just started out to forage. The coyote nablxMl the chicken so (piickly that the bird gave COYOTE 75 but one frightened squawk. Seemingly the coyote held the head and breast of the bird both at once in its jaws; also he so held it that it could not flap its wings; and he quickly and quietly bore it out of sight. The majority of the Mountain Coyotes trapped are relatively young, for it is of course the younger, less experienced individuals that most easily fall victims to the trapper's skill. Some individuals may be trapped yet escape, and these probably carefully shun traps and bait thereafter. Removal of even a small number of the younger coyotes, however, gives the others a greater chance for survival since there are fewer to use up the available food supply. Those Moiuitain Coyotes who, made wise ('educated') through experience, survive their various enemies, grow to unusually large size and probably attain to ages far above the average for the species. These particularly old, large, and crafty individuals some- times live in a locality for years and become well known to the residents of the region. One such animal was reported to us in 1915 to be living in the vicinity of Sweetwater Creek. These large individuals of the Mountain Coyote are the present day "wolves" of the Yosemite region. No true wolf is known to have occurred anywhere in middle California since about 1870. The most usual utterance to be heard from coyotes is a rapid series of rather high pitched barking notes, interspersed with shrill Avails, the whole continued for several seconds at a time. Trapped animals have been heard to give low growls and snarls, and we may infer that these weaker notes are used by the coyotes when in the wild, either toward others of their kind, or when alone and pursuing prey. The voice of the Mountain Coyote, as usually heard, is deeper toned than that of the Valley species, and so much more voluminous that to one observer it suggested comparison with a steam whistle. There is less of the high-pitched wailing, or squealing, in the voice of the Mountain Coyote, and its howling is therefore more like that of a large domestic dog. The barking choruses are most often heard in early morning or late evening; sometimes they are given during the night, especially when it is moonlight, but they are rarely heard during the middle of the day. Often, when one animal, or a pair, calls, others in the vicinity will answer. Thus, at Williams Butte, on September 18, 1915, at 5 :40 a.m., one or more coyotes off to the south began baying. These were answered by others nearby, and then the animals called back and forth for some time. At 9 :30 a.m. the same day, in broad sunlight, others were heard, and at 7 :15 p.m. there was another chorus. Loud noises sometimes start coyotes barking. On the night of July 28, 1915, at Tenaya Lake, two burros brayed, whereiipon coyotes in the neighborhood set up a succession of calls. 76 ANIMAL LIFE IN THE YO SEMITE The choriLS may, in reality, be the product of but one individual, whose intonations are such as to give the effect of two or even more voices heard simultaneously. We are unable to give any conclusive statement in this regard. The food of the Mountain Coyote includes a w^ide variety of items, some of which have been alluded to in the preceding paragraphs. Usually, little knowledge of the coyote's food habits can be obtained by direct observation, as the animals do much of their hunting and feeding during the night. Even persons whose business keeps them out of doors much of the time in good coyote country do not often see a coyote actually eating. Our evidence, therefore, is, much of it, indirect. By far the greatest amount of data now at hand has been obtained by examining faeces (drop- pings). The hair and bones of mammals, the feathers of birds, and the seeds of plants are often recognizable in the droppings of the animal, and in many instances they may be identified even as to the species. The droppings of a Mountain Coyote found in a trail at the head of Yosemite Creek basin on October 9, 1915, contained the forepaws of a Sierra Nevada Pocket Gopher (Thotnomys monticola monticola) , jaws, other bones, and hair of an adult and an immature Gambel White-footed Mouse (Pei'omyscus mmiicidatus gamheli), hair of the California Ground Squirrel (Citellus hcecheyi heecheyi), and hair of the Kocky Mountain Mule Deer (Odocoileiis hemionus hemionus). Another lot contained what appeared to be hair of the Golden-mantled Ground Squirrel. A third lot of faeces, collected near Dudley on August 9, 1920, consisted almost entirely of seeds from manzanita berries (Arctostaphylos mariposa). Deer hair is commonly found in the droppings of the Mountain Coyote, but this fact does not necessarily mean that coyotes themselves regularly kill deer. On the contrary, it is likely that much of the coyote's venison comes from carcasses of deer killed and left cached by the Mountain Lion. Ranger Townsley has told us that on April 11, 1916, near Grouse Creek, he came upon two Mountain Coyotes circling the carcass of a deer which had been killed by a Mountain Lion, and that they were evidently about to feed on the deer when frightened off by shots. However, the coyote is known to have pursued and killed deer. Young does and fawns are probably the ones most often obtained in this way. When, in early winter, the deer are overtaken by a fall of snow more than a foot in depth, progress for them becomes difficult; they may be more easily and successfully run down l)y coyotes then than in llie summer. FOXES 77 Cascade Red Fox. Vulpes cascadensis Merriam Field characters. — General appearance that of a collie dog, but size smaller; tail extremely large and bushy; ears prominent; head and body about 26 inches, tail (exclud- ing hairs at end) 16 inches, ear (about 4 inches?). Coloration (red phase) rich yellowish brown above, becoming white on belly and throat; feet and tips of ears black; inside of ears and end of tail white. Occurrence. — Rare resident in higher zones on Sierra Nevada. Recorded definitely only at Big Meadows (4500 feet altitude), northeast of El Portal, about February 10, 1916; but to be expected anywhere from this level up to timber line. Lives chiefly in forest. The Cascade Red Fox in the Yosemite reg^ion proved to be a notably elusive creature. We, ourselves, were not able to gain any direct informa- tion concerning it. On a number of occasions we saw tracks or sign which were believed to be those of this species, but we neither saw nor trapped the foxes. They must be present in only limited numbers, as even experi- enced trappers in the region, who have made good catches of other fur- bearers, have rarely taken the Red Fox. Inclusion of the species in the fauna of the Yosemite rests definitely upon a single imperfect specimen obtained through Mr. F, S. Townsley of the Park Ranger Service. This specimen was taken at a locality, Big Meadows, which lies well within the Transition Zone and hence inside the range of the California Gray Fox. And it may be that the captured fox was driven to this low level by the extreme severity which marked the winter of 1915-16. The Red Fox is quite different in appearance from its foothill relative, the Gray Fox. While exhibiting the dog-like appearance of foxes in general, the present species has proportionately larger ears, a softer and heavier coat of fur, and a more cylindrically bushy tail which looms large in proportion to the size of the animal 's body. An occasional individual of the Red Fox departs from the regular color scheme and becomes a "cross", fox or even a "black" fox. The general darkening in tone results from replacement of the red in the pelage by black. One of our local informants told of seeing a "black" fox in the vicinity of Tioga Pass in September, 1915. San Joaquin Kit Fox. Vulpes macrotis mutica Merriam Field characters. — Similar to Red Fox in general appearance, but size smaller; head and body 19 to 21 inches (480-540 mm.) ; tail 10 to 12 inches (260-310 mm.) ; ear 3 to 3% inches (80-93 mm.); weight 4 to 6 pounds (1800-2700 g.).6 Upper surface light grayish brown, gi'izzled with white; tail bushy, with end conspicuously black; under surface of body pale yellowish to white; inside of ears white. 6 Measurements from specimens taken elsewhere in San Joaquin Valley. 78 ANIMAL LIFE IN THE YOSEMITE Occurrence. — Reported from Dry Creek, north of Snelling. No specimen obtained by us in Yosemite section. Inhabits dry uncultivated prairie, living in burrows in the ground. The San Joaquin Kit Fox, or "swift," is an animal of the broad, open San Joaquin Valley, and it reaches the limit of its range at the beginning of the foothills. Only a narrow strip of territory typical of its range was included in our Yosemite section, and we did not succeed in trapping any specimens within it, but residents at both Snelling and Lagrange told us that the animals were formerly to be found in the open country lying between these tAvo towns. Kit Foxes may still exist on parts of the dry rolling lands just below the foothills, for the country there, which has not yet been brought under cultivation, seems specially suited to their require- ments. In other parts of the San Joaquin Valley, which like the Drj- Creek region are pastured to cattle but otherwise unchanged by man, Kit Foxes are still to be found. Their requirements are met by the loose sandy soil in which they can make their burrows, and by the abundance of small game such as kangaroo rats, which affect similar situations. The Kit Fox is more nearly related to the Red Fox than to the Gray Fox. It has the general form and scheme of marking observed in the former species, but the tip of its bushy tail is black instead of white as is that of the Red Fox, and its coloration generally is paler, more ashy, in tone, in keeping with the general color tone of its chosen environment. California Gray Fox. Urocyon cinereoargenteus californicus Moarns Field characters. — Form and size suggestive of a small collie dog; tail bushy; head and body 22 to 27 inches (549-690 mm.), tail (without hairs at end) 13 to 16 inches (330-410 mm.), height of ear 2% to 31^ inches (68-78 mm.); weight 7 to 10 pounds (3.2^.5 kilograms). Coloration of body and tail chiefly iron gray; stripe down middle of back and along tail to tip, black; breast, sides of body, and much of legs, rich yellowish brown; chin and middle of belly white. Voice: A sharp bark; captive indi- viduals sometimes make growling sounds. Droppings: Doglike, but smaller, ^i^ inch in diameter. Occurrence. — Common resident in Upper Sonoran ami Transition zones on west slope of Sierra Nevada. Recorded from Pleasant Valley eastward to floor of Yosemite Valley. Lives chiefly in chaparral. Solitary. The California Gray Fox is the predominant carnivorons luannnal in the great tracts of chaparral which clothe the western flanks of the Sierra Nevada. While it ranges somcAvhat outside the brushljind, it is as character- istic a member of the fauna there as is the wren-tit or the California Thrasher among birds. Indications of the presence of Gray Foxes were observed at every camp which we made in the foothills. Tracks in the dust of roadways, droppings FOXES 79 in the trails through the chaparral, accumulations of feathers in clearings where birds had been eaten, and even momentary glimpses of the foxes themselves, all testified to the abundance of the species. In fact we were led to suspect that the paucity of small mammals in certain places might be due in part to the relatively large numbers of Gray Foxes present. Estimates as to the actual population of foxes are difficult to make, but there must be, in favorable situations, at least two pairs to a square mile. The Gray Fox is often active during the daytime; the members of our party saw at least three individuals at large during the midday hours. Two explanations may be suggested for this peculiarity of behavior: (1) In the chaparral a fox would usually be as well screened from view as though it were operating under cover of darkness. (2) At certain seasons vegetable materials predominate in the diet of this fox, and it is quite as easy to forage for such food during the daylight hours. When moving about, a Gray Fox usually travels at a rapid trot, a gait which carries it over the ground with considerable speed, but without obvious effort. To judge from the tracks seen in some places, individuals do considerable scouting. In Yosemite Valley on the snowy day of Decem- ber 10, 1914, the tracks of at least three foxes were observed between Mirror Lake and the foot of the Tenaya trail. They had covered a great deal of ground, mostly off the trail, going over and under boulders and through the brush thickets in their search for prey. In general outline, the track of the Gray Fox resembles a dog's, but it is much smaller, being about an inch in each dimension. In the soft dust of roadways imprints of the claws are often made in addition to those of the four toes and the foot pad. In silhouette the Gray Fox presents a slender body, relatively large ears, and a bushy tail, though that member is not quite so large proportionately as it is in the Red Fox. The presence of much steel-gray or iron-gray in the body coloration readily distinguishes the Gray Fox from the Red Fox, which is of similar general size but has larger ears, and from the coyote, which is much larger. The most common note heard from the fox is a sharp bark, dog-like in character, and never prolonged like the wail of a coyote. A trapped fox sometimes makes growling sounds when a person approaches. It is prob- able that in the wild a fox gives voice just about as a dog would do under similar circumstances. The Gray Fox is classed as a carnivore (flesh-eater) by reason of its structure and relationship, yet it partakes extensively of food that is vegetable in nature. During the fall and early winter months we saw many fox droppings along the trails which consisted largely and often 80 AMMAL LIFE IN THE YOSEMITE exclusively of the hulls and seeds from manzanita berries {Arctostaphylos mariposa). These berries when ripe are notabh' sweet to the human taste and must be highlj' nutritious. This easily gotten food is also abundant and the berries are available over a long season, from the first of August to at least December. On the brushy slopes of the hills a fox would need to do much skilful hunting to get a sufficient supply of meat daily from cottontail rabbits, wood rats, mice and small birds; plenty of berries are to be had, however, simply for the eating. As to other vegetable food, we may note that in the stomach of a fox trapped at El Portal we found, among other items, some blades of grass; another stomach contained some finely chewed material which looked like oak-mast. As to animal food, we are able to definitely report that one stomach contained the remains of a pocket gopher; another had claws of some carnivore (which, however, may have been used as bait for traps). One lot of droppings included ribs and vertebrae of a small rodent, probably a white-footed mouse. Local trappers told us that Gray Foxes would come readily to traps baited wath 'cracklings,' even though this material was buried in the ground. The members of our field party used successfully, in addition to bacon scraps, the bodies of small birds and mammals whose skins had been removed for specimens. In only one instance were we able to affirm that a fox had devoured a quail. In Yosemite Valley on the morning of December 24, 1914, one trap in a setting put out for foxes contained the leg of a Mountain Quail. Beside the trap were fox droppings and quail feathers. The bird had accidentally gotten into the trap ; then the fox had come along and feasted. Foxes evidently prey upon small birds to some extent, though our evidence on this point is rather inferential in character. For example, while the senior author was walking along a road through the chaparral near Pleasant Valley, on May 25, 1915, there came to his ears, from a nearby canon bottom, the remonstrant chirping of a pair of Rufous-crowned Sparrows concerned over some marauder near their nest. A Bell Sparrow and a male Lazuli Bunting nearby lent voice to the demonstration. The observer approached cautiously and soon a Gray Fox was jumped in the ravine bottom. At Blacks Creek, near Coulterville, in May, 1919, a fox crossed the creek near our camp. At the instant the fox appeared a male Valley Quail, standing guard nearby, uttered a series of exjilosive sputter- ing notes indicative of great concern. Judging from specimens obtained in the foothill country, the breeding season of the Gray Fox occurs in the spring months. No data were obtained locally as to th(^ nuni])er of young, but elsewliere it has been ascertained to average four in a litter. BING-TAILED CAT 81 California Ring-tailed Cat. Bassariscus astutus raptor (Baird) Field characters. — Body slender and tail long, the two of about equal length; general bulk that of house cat; ears broad, scantily haired; head and body IS^/^ to 15i/^ inches (346-396 mm.), tail 13%-15% inches (350-392 mm.), ear about 1% inches (45-47 mm.) ; weight 28-39 ounces (0.8-1.1 kg.). Body coloration drab brown, shaded with black on back; under surface white; tail full-haired, with alternate rings of black and white; a narrow black ring around eye, this nearly surrounded by white. Occurrence.- — Moderately common resident in Upper Sonoran Zone on west slope of Sierra Nevada. Eecorded from Pleasant Valley eastward to El Portal ; also taken in one verified instance on floor of Yosemite Valley. Inhabits rocky and brushy places, iisually near streams. The California Ring-tailed Cat, as might be inferred from its general scheme of coloration and particularly from its zoned tail, is a relative of the raccoon. In early days it was kno\vn commonly as 'miner's cat,' because many of the gold-seekers in the Sierras kept the animal as a free- roaming pet to rid their cabins of native mice. It has less often been called ' civet cat, ' a doubly unfortunate choice of name, first, because the ring-tail is in no wise related to the Old World civets ; second, because this particular name is locally applied by trappers to our Spotted Skunk. The ring-tail is not at all nearty related in either structure or habits to the cat family. In the fall and early winter of 1914 trappers in the vicinity of El Portal captured a number of Ring-tailed Cats; the species seemed to be common in the nearby caiions. One specimen was taken by our party at Pleasant Valley on May 27, 1915 ; and in early February of 1920 Mr. F. S. Townsley obtained an individual in Yosemite Valley. The California Ring-tailed Cat is of rather gentle demeanor, and hence a desirable animal to keep as a pet. In the wild it seldom causes any concern to people resident in the territory where it occurs, for its prey is almost entirely the smaller native animals. Occasionally in dusty places the small, somewhat cat-like tracks of the Ring-tailed Cat may be seen in the early morning, showing where it has been hunting abroad at night in search of wood rats, white-footed mice, and similar game. It spends the daytime in small caves among rocks or in the hollows of logs or trees. California Coon. Procyon lotor psora Gray Field characters. — Body size that of dachshund; legs and tail both short; toes of all feet long. Head and body 18 to 23 inches (460-585 mm.), tail IQi/o to 12 inches (264-308 mm.), ear 2 to 2i/2 inches (52-65 mm.), weight 9 to loVa pounds (4.1-7 kg.) [these figures from specimens taken elsewhere in California]. Body coloration grayish brown, hairs on back tipped with black; tail with, alternating rings of black and pale ashy brown; face crossed by a conspicuous black band. Tract: 'hand-like'; impressions of all five toes and of 'palm' showing distinctly. 82 AMMAL LIFE IX THE TOSEMITE Occurrence. — Common resident in Lower and Upper Sonoran zones, less coinniou in lower part of Transition Zone, on west side of Sierra Nevada. Recorded from Snelling and Lagrange eastward to El Portal and Hazel Green. Lives chiefly in vicinity of streams, foraging on ground but taking shelter in hollow trees. Solitary; nocturnal. The California Coon, or "raccoon" in the book terminology, is abundant in the lowland and foothill districts of the Yosemite region. It is essentially an inhabitant of the stream-side and seldom ventures any great distance away from the banks of rivers or creeks. Yet its requirements with regard to water are rather simple and it will often be found in caiion bottoms where in summer there is little more than a trickle of water or a series of disconnected seepage pools. Hand-like tracks in the mud of creek banks, in evidence of a coon's presence, are much more likely to be seen than the animal itself. For coons are exclusively night prowlers and spend the daytime in hollow trees or other similar retreats. In the Yosemite region we found tracks in the neighborhood of every camp below 4000 feet altitude, and on one occa.sion tracks were noted along a creek near Hazel Green, altitude 5665 feet. In the latter case the animal had probably wandered up the creek from some lower station to the south. At Snelling the species seemed to be of maximum abundance ; one trapper had 25 skins which had been obtained from his headquarters at a ranch a mile west of the town. Throughout much of their load range coons must depend upon natural food, rather than that obtainable around human habitations. This food is no doubt varied, and includes both animal and vegetable materials. At Smith Creek, according to Mr, Donald D. McLean, coons live, in some part, on frogs. On Sweetwater Creek in late October the coons had been visiting a garden where grapes and other fruits were growing. Sierra Pine Marten. Martes caurina sierrae Grinnell and Storer Field characters. — Size of small domestic cat, but form more slender (pi. 23b) ; tail somewhat bushy, about one-half length of head and body. Head and body 15 to 16l-> inches (374-420 mm.), tail (without end hairs) 6% to 7Vi! inches (170-194 mm.), ear 1V,-1% inches (29^3 mm.), weight 26 to 33 ounces (746-929 grams). Coloration plain brown above; paler on under surface with an area of buff or orange on throat, varying in extent in different individuals; tail brown, becoming blackish toward tip. Occurrence. — Common in Hudsonian Zone on Sierra Nevada, where recorded from near Glen Aulin and Vogelsang Lake eastward to Lyell Canon. Inhabits rock slides chiefly. The Pine Marten, or American Sable as this animal is sometimes called in books l)y reason of its relationship to the sable of the Old World, is rather common in the higher parts of the SiiM'ra Nevada. We found the species only in Ihc Hudsonian Zone, Ix'twcen altitudes of 8000 and 10,350 feet; it seems to remain lliere Ihroughoul the y<'ar. MABTEN 83 The common name of this animal would suggest that it is an inhabitant of the forest, and so it is in Canada and Alaska; but the race inhabiting the Yosemite region seems to have departed from its ancestral predilections in some measure, for it here lives about the rock slides. Our knowledge of the marten locally was all gained during the summer season when its addiction to the talus rocks is marked ; but it may be that, in winter when the rock slides are buried in snow, the animals live in the adjacent forest. Only winter observatoins in the high mountains can determine this par- ticular point. None of our party happened to see any Pine Martens except those trapped for specimens ; but a group of campers located on Fletcher Creek in September of 1915 reported seeing four or five in a rock slide opposite their camp. It is not unlikely that watchful visitors in the Hudsonian Zone may, with some frequency, catch sight of martens, as well as other interesting but elusive denizens of the rocks. In general form, especially in its relatively slender ho&y, the Pine Marten resembles the weasel. But the tail is much more heavily haired and the tip is not abruptly black. The facial expression, with pointed features, recalls strongly that of the weasel. The marten never gets white in winter, but retains its brown color throughout the year. It might be expected that the marten would pursue game of a size proportionate to its own bulk ; but its constant residence in the rock slides makes it seem likely that the decidedly smaller conies and Bushy-tailed "Wood Rats are the most important items of its food. Our specimens were caught in traps baited with the bodies of small mammals and birds; in one case fish w^as used. Pacific Fisher. Martes pennanti pacifica (Rhoads) Field characters. — Size twice that of a large domestic cat; body rather slender (pi. 23a), tail bushy, more than half length of head and body; ears short and rounded. Head and body 20 to 25 inches (520-625 mm.), tail (without end hairs) 15 inches (375-380 mm.), ear 1^2 inches (35-40 mm.); weight (from specimens taken elsewhere in California) 8 to 10 pounds for males, 4 to 5% pounds for females. Coloration black on tip of nose, legs and feet, hind part of body and whole of tail; rest of body drab brown (many of the hairs black-ended), becoming grayish on head and shoulders; occasionally white spots on chest and belly. Occurrence- — Moderately common resident in boreal region of Sierra Nevada. Winter specimens taken from Big Meadows and Tuolumne Grove Big Trees eastward to Chin- quapin and floor of Yosemite Valley at Pohono Bridge. Seen in head of Lyell Canon at about 11,000 feet altitude, July 18, 1915. Mostly inhabits forest. Solitary. Information concerning the Pacific Fisher in the Sierras, save for that obtained through trapping, is slow in accumulating. In fact, except for the specimens obtained from trappers in the western part of the Yosemite 84 ANIMAL LIFE IN THE YO SEMITE National Park during the winter months, we have only a single observation to record. The species seems to be even more retiring in its habits than is the Pine Marten. The Pacific Fisher is a considerably larger animal than the Pine Marten, the weights of the two being in a ratio of about 31^ to 1. Both exhibit the comparatively slender form of body which characterizes so many members of the Mustelidae, the chief family of the fur-bearers. The fisher is some- what longer legged and its tail is decidedly longer proportionately than the marten's. In coloration the fisher is more varied tlian the majority of its relatives, and its fur is long as well as dense. Naturally, therefore, it is a species especially sought for the fur trade. All of the w'inter records of the fisher in the Yosemite region are from a narrow belt of country in the western part of the Park because it is only or chiefly in that area that trappers have plied their trade. To judge from the habits of the fisher in other parts of its w'ide range, some individuals of the species probably remain during the winter months in the Canadian and even in the Hudsonian Zone of the Yosemite section. So far as we know no trapping or observation has been carried on in the heart of the high Sierras during the winter months ; consequently, there is an almost total lack of information concerning the distribution and habits of the mammals which winter there. The one definite record for the fisher on the floor of the Yosemite Valley was made in the middle of winter, February 14, 1920, w'hen an individual was obtained near the Pohono Bridge. The species does not stray onto the Valley floor very frequently, else, with the numerous campaigns of trapping (for coyotes) carried on there during the winters of different years, it would have been captured more often. The fisher, to judge from its structure, especially from the sharp and curved claws, is an animal well fitted to climb trees. Its feet, at least during the winter months, are well furred between the toe and foot pads. This fact suggests that it also travels about to a considerable extent on the snow. The habits of the fisher in the woods of Canada show it to be a truly carnivorous species, for it there destroys many of the fur animals caught in traps. While four members of our party were ascending Mount Lyell on the morning of July 18, 1915, a good view was obtained of a Pacific Fisher. As we crossed a little de])ression at about 11,000 feet altitude, we seared the animal up Jiiul it bounded lightly ixwny over the rocks and snow with the agility of a cat. The snow was 'pocketed' at this setuson and the animal had to leap deftly from one narrow ridge to another as it made off across the snow field. As it ran we noted the slender legs, slim body, and long tail, the light patch on the forehead and another on the back. The animal resembled a marten somewhat, \n\\ was larger. It made leaps of about 2 FISHEB 85 feet, and finally disappeared from sight behind the very last patch of stunted white-bark pines on the north side of Mount Lyell. When first seen, the fisher was about 200 yards off ; as it ran it paused occasionally to look back in our direction. Its whole demeanor sug'gested that of a house cat making its way over a rough surface at a rather good rate of speed. Sierra Nevada Wolverine. Gulo luscus luteus Elliot Field characters. — Size and proportions of heavily built dog; body stout (pi. 23c), rather broad; legs short, feet big; tail quite short. Head and body 27-29 inches (682-742 mm.), tail about 10 inches (250-260 mm.), ear about 2 inches (50-55 mm.); weight 17 to 25 pounds (7.6-11.3 kg.). Coloration above, yellowish brown, dark on lower back; head (except crown), feet, under surface of body, and end of tail, blackish. Occurrence. — Sparse resident of Hudsonian Zone along crest of Sierra Nevada. Recorded definitely in head of Lyell Canon at altitudes of 10,100 and 11,000 feet, July 26 and 25, 1915. Probably inhabits sparse forest. Solitary. The wolverine is a rare animal anywhere on the Sierra Nevada, and it dwells only in the highest parts of these mountains. In consequence there is but scant information concerning it locally and much of that is hearsay. Only one of the local trappers in the Yosemite section had anything to relate concerning the species and he merely reported one killed in the region prior to 1914, Inclusion of the species here is based upon the capture of two individuals at the upper end of Lyell Canon, late in July of 1915, by Mr. Charles L, Camp of our party. Our station at the head of Lyell Caiion was at 9800 feet, but trapping was carried on up to timber line toward Mount Lyell in an effort to obtain various desirable species. For nearly a week a certain setting of steel traps was visited daily and baited with marmot bodies and other similar material. These traps were placed on bare rocky ground at the side of a thicket of white-bark pines at timber line (11,000 feet) on a rocky ridge between the McClure and Lyell forks. The snow was 4 feet deep in places near by. On July 25, a female wolverine was captured in this setting, and the day following an adult male was taken in another 'set' not far off, at 10,100 feet. The first individual was held securely in all three traps. Nevertheless, it struggled violently, and from time to time uttered grunting sounds. When the observer placed his gun within reach, the animal quickly and easily bit off a piece of the black walnut stock. The second wolverine captured was held by one hind foot in a steel trap, but this did not hinder it from going through a variety of motions limited only by the length of the trap chain. It climbed readity into a nearby wind-distorted lodgepole pine about three feet in diameter, using the claws in holding on to the trunk. Several times while being watched 86 ANIMAL LIFE IN TUE YOSEMJTE the animal started to dig into the ground, throwing up the earth at a lively rate; it would then turn over on its back and wallow in the cool earth, putting its feet into the air while doing so. Twice the wolverine sat up on its haunches with the forefeet against its breast after the manner of a bear. When approached very closely it made a lunge at the aggressor, uttering hoarse growls somewhat like those of a badger, and wrinkled up its nose, exhibiting its blunt teeth. The iris of this wolverine looked black; but when the pupil was dilated, the aqueous humor of the eyeball made the eye look green at certain anglas. In several other places, as at Vogelsang Lake and Fletcher Lake, tracks were seen which, chiefly through a process of elimination, were ascribed to the wolverine. The only other large carnivore in the high mountains is the Mountain Coyote. But the wolverine's track is not dog-like; the sole pad on the forefoot is divided up into small units, whereas the sole pad of the coyote is a single unit. The badger, which also has a relatively large track, has an elongated triangular foot pad. Mountain Weasel. Mustela arizonensis (Mearns)^ Field characters. — Body about as long as that of California Ground Squirrel, but much more slender (fig. 9b) ; tail about half length of head and body. Head and body 81^-101/2 inches (211-269 mm.), tail 5i,4-6% inches (132-160 mm.), ear %-l inch (21-26 mm.), weight 7l^-12^^ ounces (212-345 grams); among adults, males are larger than females. Coloration in summer uniform brown above, under surface rich creamy yellow; in winter, solidly white above and below; end of tail black at all seasons. Occurrence. — Moderately common in Transition, Canadian, and Hudsonian zonos on both slopes of Sierra Nevada. Eecorded from Merced Grove Big Trees and Chinquapin eastward to Walker Lake and Mono Lake Post Office. Common on floor of Yosemitc Valley. Lives around rock piles and old logs and under buildings. Solitary. The weasel is a fearless animal, and active at all seasons of the year. Visitors to the Yosemite region therefore frequently see it, sometimes at very close range, both in the Valley and in the higher mountains. The weasel is one of the most bloodthirsty of all of its tribe; the wild birds and mammals know this as thoroughly as do naturalists, for the presence of a wea.sol in any locality is immediately announced by cries of alarm from the native denizens. The weasel's body is extremely slender (fig. dh) ; so small is the girth that it can easily make its way into the retreat of a ground squirrel or even into the burrow of a pocket gopher; and it readily enters the nests of those rodents which live among rocks or 7 Another species, the California or Yollowcheeked Weasel, with whitish i>atches on the nose and cheeks, common in the Lower and l)pi)or Sonoran zones of southern and central California, probably occurs in the lowland and foothill districts of the Vosemito region, though we obtained no s])ecimens. We were told of a weasel having bwn seen at SnoUing; presumably it was of this lowland species, Mu^ilclo .rantho(itnn.i Gray. WEASELS 87 in hollow logs or trees. Furthermore, the weasel is an adept climber and can run up or down the trunks of the smaller trees as readily almost as a tree squirrel. By reason of its structure and capabilities, it is therefore able to prey upon a much larger variety of animals than any other species of carnivore. Fig. 9. (a) Sierra Least Weasel; Vogelsang Lake, August 31, 1915. See p. 89. (ft) Mountain Weasel; Ten Lakes, October 8, 1915. See p. 86. (c) Pacific Mink; Merced Lake, August 23, 1915. See p. 89. All photographed from freshly taken animals; reproduced about % natural size. The body coloration of the weasel is unique among our predatory mammals. It changes abruptly with the seasons, being solidly white in the winter months and brown and yellow in the summer season. The weasel is thus able to hunt the year round, well concealed in its protective color- ation be the season that of blanketing snow or of brown logs on the bare ground. In the summer months we found weasels at practically all of our camps in the territory from the 4000-foot contour up to the head of Lyell Canon, at 9800 feet altitude. In Yosemite Valley, in both the winter and summer months, weasels are observed commonly. On December 20, 1914, a 'white' 88 AXIMAL LIFE IX THE YOSEMITE weasel was reported near Sentinel Hotel. December 9, 1914. tracks were seen in the .snow on the Yosemite Falls Trail, and December 23, the same year, tracks were seen on the Vernal and Nevada Falls trail. In the latter case runways crossed the trail in many places, but these did not extend very far out on the unbroken snow. The wea.sels were then evidently livin«r among the rocks which bordered the trails, for the short runs often led into holes about l^/^ inches in diameter burrowed in the snow covering the rocks and adjacent bushes and small trees. During the rather brief stops which our party made at the various camps occupied in the Yosemite country, we saw many of these animals. At Chinquapin, on June 19, 1915, one of our party came upon a wea.sel in a small pile of old logs near a clearing. The wea.sel disappeared. The observer waited ten minutes and then went cautiously around to the other side of the pile where he found the animal peeking out at him curiously. When we stopped near the Tuolumne Meadows camp of the Sierra Club in late July of 1915, one weasel was shot right in camp as it made its appearance under a log beside a small rocky eminence. Another individual was seen close by, at the base of the same rock heap, where it was traveling in long bounds along the boulders. These two individuals caused par- ticular concern to a number of AVhite-crowned Sparrows which had their broods in the near vicinity; the birds evinced their anxiety over the presence of the enemy with many sharp notes of alarm. In Yosemite Valley on June 25, 1920, a Mountain Weasel was discovered through the excited calling of a pair of Spurred Towhees in a cascara thicket. This weasel took refuge from our pursuit up in an apple tree ; there he dodged about among the branches and repeatedly looked down at us, monkey fashion. The black-appearing head, big round ears, and beady eyes had a strikingly alert expression. In Yosemite Valley domestic cats were kept by the local residents until about 1908 when they were banished by order of the park authorities. The following year mice swarmed ; then wea.sels began to be noted and they have been observed there in numbers ever since. We were told by Mr. C. W. Baker that on July 25, 1915, there was a brood of young to be seen playing about an occupied tent. The same informant stated that wea-sels were common about the horse barns and that they came out and watched like cats when bales and sacks were moved about and mice were likely to api)ear. Twice, we were told, weasels in the Valley had been seen carrying pocket gophers. At Tuolumne Meadows a packer told us that he saw one kill a 'picket-pin' (lidding Ground Sciuirrel) ; the wea.sel had tlie s(juirrel by the back of the neck. At Walker Lake on September 12, 1915, a Red S(iuirrel was caught in one of the 1ra|)s in a setting ])laee(l between the butts of two logs. Later, WEASELS 89 a Mountain Weasel happened along and nearly consumed the squirrel before it in turn was caught in another of the traps in the same set. On the same day the greater portion of another weasel caught elsewhere had been eaten, but there was nothing to indicate the identity of the animal which had attacked the victim of the trap. It is evident from the first mentioned case and from other trapping experiences not specifically cited that weasels will eat dead flesh, even when not fresh. A Mountain Weasel three-fourths grown, living in a den under a willow clump at the edge of the lake, was taken at Mono Lake Post Office on June 30, 1916. There were many droppings at the entrance to the den. Sierra Least Weasel. Mustela muricus Bangs Field characters. — Size small and form slender; our smallest carnivore (fig. 9a); body about as large as that of Tahoe Chipmunk; tail small, round, about % length of head and body. Head and body 6i/^ inches (159-161 mm.), tail 2% inches (59 mm.), ear Ys inch (8 mm.), weight about 2 ounces (56-62 grams.). Coloration in summer season chocolate brown above, under surface white; end of tail blackish. Occurrence. — Sparse resident in Hudsonian Zone along Sierra Nevada. Eecorded at Ten Lakes (9200 feet altitude), October 10, 1915, and at Vogelsang Lake (10,350 feet), August 31, 1915. Lives in or about rock slides. Solitary. The Sierra Least Weasel, as its name suggests, is much smaller than its better known relative, the Mountain Weasel. We obtained two specimens, as recorded above, and no others were seen ; it would seem from our experi- ence both in the Yosemite region and elsewhere that the species is decidedly less numerous than is the Mountain Weasel. The Least Weasel is a member of a rather wide ranging group which fills some small corner in the economy of nature not occupied by the larger species. So far as our local informa- tion indicates, the Least Weasel is an associate of the Pine Marten, Yosemite Cony, and Bushy-tailed Wood Eat. At Vogelsang Lake on August 31, 1915, the senior author, while making the rounds of his traps before sunrise, heard two conies across the lake basin (pi. 18a) 'screeping' vociferously. Upon going to the rock slide, he saw these animals running excitedly in and out of the crevices between the rocks. Presently a Least Weasel appeared, crossing between two rocks. Soon, it put its head out from under a flat rock within 30 feet of the observer, who shot it. The inference that this weasel is a regular enemy of the conies and is so recognized by them seems justified. Pacific Mink. Mustela vison energumenos (Bangs) Field characters. — Body size about that of California Ground Squirrel, but tail short, about half head and body (fig. 9c) ; head and body ll%-13ii inches (297-337 mm.) ; tU 6-6% inches (150-170 mm.); ear about V^ inch (11-14 mm.); weight 131/4-18% ounces (377-530 grams). Coloration deep, dark brown, only a little paler on under surface; end of tail blackish. 90 AXIMAL LIFE IS THE YOSEMIIE Occurrence. — Recorded definitely only at Merced Lake (altitude 7500 feet), but likely to bo found on any of the streams up to this altitude. Inhabits streams and ponds and their margins. The Pacific Mink was collected in only one place in the Yosemite region ; but, to judge from other information at hand, it is certainly of more wide- spread occurrence than this record would indicate. In Yosemite Valley above the Pohono bridge an animal which was believed to be a mink was seen swimming in .the river November 26, 1914. The species was reported to us as occurring in the neighborhood of Mount Bullion and on the South Fork of the Merced River. On one occasion while at the Farrington Ranch east of the Sierras, near Williams Butte, Mr. Dixon saw tracks of a mink along a creek, and a few days later a resident of the vicinity saw one of the animals in a pasture. The mink has a moderately slender body and uniform general colora- tion, both of which features indicate its relationship to the weasels and the marten. It is, however, closely restricted to the vicinity of water. As may be expected from such a choice of habitat, its diet consists largely, if not exclusively, of fish. Were it abundant in the Sierra Nevada we might look upon it with concern as an enemy of the trout, but the species is present in such small numbers that no fear need be felt on this .score. The animal is evidently nocturnal in its habits, else we should have more frequent reports of it from the many fishermen who patrol the banks of the Sierran waters where trout abound. At Merced Lake three specimens of mink were taken on August 23, 25, and 28, 1915, all being obtained within 20 feet of running water. The bait in each case included heads and entrails of trout. One individual, probably just caught, when approached in the trap was very lively. It gave a series of loud, shrill, rasping cries, and when threatened showed its teeth and grinned cat-like. California Spotted Skunk. Spilogale phenax phenax Merriam Field characters. — Size slightly less than that of California Ground Squirrel; tail slightly over half tho length of head and body. Head and body 9 to 12 inches (232-300 pim.), tail 5Vi to G'/^ inches (ISij-lfiO mm.), ear about •% inch (15-20 mm.), weight 10 to 21 ounces (27G-600 grams). Coloration of body V)lack, with spots and irregular short stripes of white; end of tail white. 'Skunky' odor, same as that of Striped Skunk. Occurrence. — Common resident in Lower and Upper Sonoran zones, and sparingly in Transition Zone, on western slope of Sierra Nevada. Recorded from Snelling and Lagrange eastward to floor of Yosemite Valley. Seeks shelter in burrows of other maiiimals and under piles of logs or rocks; forages in open at dusk and during the night. The Little Spotted Skunk, not infrequently referred to lus "hydrophobia skunk," and known to most trappers as "civet eat," is a coninioii resident of the lower western i)()rli()n of the Yosemite region, and, in small numbers, SKUNKS 91 reaches the floor of Yosemite Valley. Locally it was found very commonly at Snelling ; probably its maximum abundance is in that direction. In Yosemite Valley the species came to our notice only along the warm north side. One was trapped December 29, 1914, in the talus at the foot of Indian Caiion, where it had a retreat beneath a granite boulder. Another was taken June 25, 1915, beneath a boulder pile near the lower end of the Yosemite Falls trail. The Spotted Skunk makes use of natural retreats and of the burrows of other mammals. Our records indicate that specimens were taken not only near crevices or holes under rocks, but at the mouths of ground squirrel burrows, and near old badger holes. The food of this skunk, as of its larger relative, is quite varied, includ- ing small mammals, insects, and vegetable materials of several sorts. The Spotted Skunk is provided with glands near the base of the tail which, when the animal is provoked, emit a malodorous secretion. To our nostrils this odor does not differ in strength or quality from that of the Striped Skunk. Striped Skunk. Mephitis occidentalis Baird Field characters. — Size of adult about that of domestic cat; tail nearly as long as head and body and very bushy. Head and body 12i/^ to 171/4 inches (318-440 mm.), tail 11 to 13y2 inches (280-345 mm.), ear about % inch (15-20 mm.), weight Si/g to 8% pounds (1.5-3.8 kg.). Coloration black except for a narrow line of white up middle of forehead, and a white area beginning on hind neck and continuing backwards, divid- ing into two stripes which extend to rump and usually run out on either side of tail; more or less white also on bases of tail hairs. 'Skunky' odor characteristic. Occurrence. — Common resident at lower altitudes on both slopes of Sierra Nevada. Eecorded on west slope from Snelling and Lagrange eastward to Sweetwater Creek, Yosemite Valley, and Chinquapin; east of mountains in vicinity of Williams Butte. Lives in holes in ground and in culverts and under rocks and buildings ; forages far and wide at dusk and during night. The Striped Skunk needs no introduction. It has long been sought after because of its valuable fur, and it is also well known in the environ- ment of farms even in settled portions of the country. Persons who walk abroad in the early evening along the country roads of the Yosemite foot- hills are likely to encounter this animal as it starts out on its nightly forays ; for the skunk, unlike most other wild animals, does not take to cover at the approach of a human being. The Striped Skunk is nearly twice the length of, and from 4 to 6 times as heavy as, the Little Spotted Skunk. Its body is heavy and the fur is relatively long. The hairs on the tail are often as much as 5 inches in length, and give to this member a plume-like appearance. Indeed, when held aloft, as it is when the skunk is disturbed, the tail constitutes its most conspicuous feature. 92 ANIMAL LIFE IN THE YOSEMITE In the lower portion of the Yosemite region skunks make extensive use of ground squirrel burrows as dens, appropriating those which are deserted or possibly, even, holes from which the rightful owners have been evicted. It likewise uses deserted badger holes to a considerable extent. On the mesa-prairie near Snelling, Striped Skunks were trapped fully three-fourths of a mile from the nearest bluff of the foothills; and it seemed as though the animals must have been foraging abroad fully this distance, as no burrows were found short of the bluffs. Relatively large numbers of Striped Skunks are trapped by the resi- dents of the region both for their fur and because of the depredations which they commit about poultry houses. But despite this draft on the population the species has maintained itself in goodly numbers. The tracks are to be seen commonly in the morning along dusty roads through the foothills. As one of us wa.s motoring up the Coulterville Road not far above Lagrange one moonless night in August, a Striped Skunk was sighted in the road ahead. The beast was traveling up-grade in the right-hand wheel rut, ambling along at the regulation matter-of-fact rate characteristic of the species. As the machine approached, going in 'low,' the skunk accelerated its pace in no perceptible degree; neither did it leave the rut. In order to avoid the consequences of a rear-end collision, the driver, the last instant it was yet possible, simply had to turn out to the left, leaving the skunk still pursing its own course when the shadow-limit from the lights cut it from view. California Badger. Taxidea taxus neglecta Mearns Field characters. — Up to twice size of domestic cat; body flat, depressed (pi. 246 and c) ; legs short; tail short, one-fourth head and body; feet large and claws stout and long. Head and body 2014-24 inches (520-610 mm.), tail 5-6% inches (125-170 mm.), ear lVfe-2 inches (30-50 mm.) ; weight Qi^-l? pounds (4.3-7.7 kg.) [extralimital speci- mens included in these measurements]. General coloration yellowish brown, grizzled with white; feet and top of head black; a prominent streak of white from nose over middle of crown to between shoulders (pi. 24c) ; side of head white with a large patch of black on cheek. Voice : Low grunting and pulling noises. Occurrence. — Resident in certain parts of the Yosemite region, irrespective of altitude. Recorded from Snelling, Lagrange, Pleasant Valley, Smith Creek (6 miles east of Coulterville), Vogelsang Lake, Tuolumne Meadows, Lyell Caiion, and near Williams Butte. Lives in oi>cn country; makes burrows in ground. Sometimes abroad in daytime. Usually solitary. The California Badger is found at numerous localities in the Yosemite region, from the San Joaciuin Valley on the west to Mono Valley on the east, and it ranges upward to an altitude of 10,350 feet. Yet it iloes not occur continuously over our Yosemite section as do several other wide- BADGES 93 ranging species like the Gambel White-footed Mouse and Red-shafted Flicker. Its distribution is controlled by the presence or absence of flat clear areas of soil, rather than by temperature or any of the other factors which limit the ranges of most animals. Thus, on the uncultivated level lands of the San Joaquin Valley, the badger is, or was originally, common ; in the foothill districts where there are but few meadows or other level open spaces, it is scarce or wanting ; in the main forest belt it is altogether absent; while on the high meadows near the crest of the Sierras and on the floor of the Great Basin, east of the mountains, it is again to be found in numbers. In settled portions of the San Joaquin Valley the badger has been reduced or exterminated by man, chiefly because the large holes (pi. 24rt) which it digs in the ground are a menace to horsemen riding over the country. On the whole, however, the badger is a beneficial species, for its habitual food consists of rodents, like the ground squirrels and pocket gophers, most of which happen to be harmful to agriculture. In the high Sierras, where the relation between rodents and carnivores is still almost in its original condition, the badger is a relatively common animal. On Tuolumne Meadows in the summer of 1915 it was judged to be the most abundant carnivore present, with one exception, the Mountain Weasel. The badger 's whole being is organized for digging. The body, especially the trunk region, is thickset and muscular (pi. 245). The legs are stout and short so that they can get an effective purchase. Both pairs of feet are disproportionately large, as compared, for example, with those of a Sierra Marmot. The claws on all the feet are large, those of the forefeet being especially long and heavy. In addition, the badger is curiously flattened horizontally in the general configuration of its head and body; this 'pancake' effect is emphasized by the greater length of the overhairs along the sides of the body. The ears are short (pi. 24c), the eyes rather small, and the head is joined directly onto the body, with no definite neck region. When hunting, the badger specializes in a method rarely used by any of the other carnivores of the region. The other predators hunt chiefly by stealth ; the badger uses its prodigious strength and special equipment for the purpose and digs its victims out of their retreats. Nature has provided the badger with some means for locating accurately the under- ground nests of pocket gophers, ground squirrels, and rabbits. Whether smell or hearing or both function in this, we do not know. But once an occupied burrow is located, the badger quickly digs out and feasts upon the luckless inhabitants. During the summer of 1915, the work of the California Badger was much in evidence on Tuolumne Meadows and the floor of Lyell Caiion. 94 ANIMAL LIFE IN THE YOSEMITE The gophers had moved up to occupy the margins of the meadows, and the badgers had concentrated their activities in these area-s, which had a maximum gopher population. Time after time we saw places where we inferred that gophers had been dug out. In the midst of an area showing new surface mounds and perhaps some winter earth-cores, there would be a hole 8 to 12 inches in diameter, with the torn remains of a gopher's nest at the bottom and signs of badger on the ground above. Three such excavations were noted by the junior author on one day in July, 1915, while traversing the floor of Lyell Cauon. Belding Ground Squirrels are probably captured to some extent by the badger in the mountains, as are California Ground Squirrels, in the lowlands. On Tuolumne Meadows, July 11, 1915, a trap sot in a locality where gophers and evidences of badger work were common caught a badger. The remarkable strength and energy of this individual, as an example of the species, were illustrated in a striking way. The animal had been caught by one hind foot. With its forefeet it had scraped up the earth within a circle of 3 to 4 feet diameter, the limit of its reach, and this earth had been accumulated in a flat-crowned mound. Its intention had been, presumably, to escape by digging, and it had stopped only when the accumulating earth had made further work impossible. On top of this mound the badger was squatting (pi. 24&). On two occasions while our party M'as at Tuolumne Meadows, badgers were found at work during the afternoon. One animal was discovered digging in a hole in the ground. It was already below the surface, "kick- ing up the dirt at a lively rate," and when come upon, it quickly plugged the entrance so that further observation of it was impossible. The other animal was out on the surface of the ground near the border of a meadow. It ran quickly up a sidehill, and, in spite of its seeming clumsiness, outdid the observer in his attempt to follow. This badger also went into a hole, the opening of which it soon blocked with earth from within. At Pleasant Valley Mr. J. B. Varain told us that he once opened a badger den on a neighboring hill and found at the bottom two young which were "nearly pure Avhite. " There was no nest of any sort. Near the Farrington Ranch, southwest of Mono Lake, a half-grown badger was captured in late June, 1916 (pi. 24c). On one occa.sion it was let go free on the ground so that something of its habits might be observed. True to its kind it immediately commenced to dig, but continued only long enough to make a shallow excavation barely deep enough to hide in. A gopher or mole under similar eircumslnnces would not only have tunneled out of sight, but would have kept on going. At any unusual noise the young badger would put his head out of the hole and look about. BADGER 95 Its general behavior was like that of adult badgers seen elsewhere, but it displayed little or none of the combativeness which characterizes the full- grown animals. Northwestern Mountain Lion Felis oregonensis oregonensis Rafinesque Field characters. — Appearance cat-like j size of a mastiff dog; tail long and slender; head and body about 4 feet, tail about 2i/^ feet; ear about 3i/^ inches; weight, adult males about 135 pounds, adult females about 100 pounds. Coloration rich reddish brown above; chin and throat and middle of under surface white; outer sides of ears, nose, feet, and end of tail blackish. There is also a 'gray' phase where the pelage is grayish brown rather than reddish brown. Trades: cat-like, usually wider than long, 3 to 41/^ inches across; heel pad wide. Occurrence. — Eesident in moderate numbers on west slope of Sierra Nevada, chiefly in Upper Sonoran, Transition and Canadian zones. Lives in both brushy and forested country. Usually solitary. The Northwestern Mountain Lion, which is also known as cougar, panther, and puma, is the second largest carnivorous mammal in the Yosemite region, being exceeded in size only by the bears. The Mountain Lion is large and strong enough, no doubt, to prey upon human beings if it so chose; but instead of being the terror of the country, as are lions and big cats in other parts of the world, our lion has practically never been known to attack a person, and indeed very seldom does it come to notice at all. Many persons, even woodsmen and hunters, long resident in regions where Mountain Lions occur, have never so much as caught sight of one. And in spite of the hundreds and even thousands of persons who camp each summer in the mountains, no one has been reported to have been molested by lions. In general appearance the Mountain Lion, save for its far larger size, is much like a domestic cat. The head is short and massive, the forelegs are of heavy build, the body rather slender, and the tail long and cylindrical with an even covering of hair clear to the end, but with no 'tassel.' The Mountain Lion is several times the size of a large Mountain Coyote or a Sierra Nevada "Wolverine. As to actual size we will cite, in the absence of carefully measured specimens from the Yosemite region, two typical indi- viduals killed at a point farther north in the Sierra Nevada (Lynchburg, Placer County). The male measured 6 feet 6I/4 inches from tip of nose to end of tail (excluding hairs), the tail was 2 feet 6i/^ inches, and the ear S% inches. It measured 281^ inches in height at the shoulder and by two reliable observers was estimated to weigh about 134 pounds. The female measured 6 feet 4 inches over all, with tail 2 feet 6 inches, and ear S^/^ inches. Its height at shoulder was 27^2 inches, and estimates of weight were 95 to 100 pounds. 96 AXIMAL LIFE IX THE YOSEMITE The range of the Mountain Lion in the Yosemite region is not so definitely bounded as that of many other species of mammals. In general the lions are to be found in the territory occupied by the Mule Deer, namely, the Canadian, Transition, and Upper Sonoran zones. There is to some extent, doubtless, a shifting of the lion's range in unison with the seasonal migrations of the deer. In the winter of 1915-16 Mr. Jay Bruce secured 11 lions in a rather limited tract of country near "Wawona, and others were obtained by him in later years in the same region, a total of 31 being taken in the three winter seasons, 1915 to 1918. During the winter of 1915-16 at least 4 lions were obtained by other hunters in and about Hetch Hetchy Valley. Lions are noted not infrequently in the vicinity of the Dudley ranch on Smith Creek, east of Coulterville. Several individuals usually winter on Pilot Peak ridge where there are many deer. But Mountain Lions are likely to turn up at any point in the region. Thus, one was reported to have lived in the vicinity of Williams Butte, near Mono Lake, prior to 1910. And in 1920, about June 23, a lioness was shot under the road bridge across the Crocker-Hoffman canal halfway between Merced and Snelling, out in the San Joaquin Valley. Another is said to have been killed in the same locality a few days later. Lions are also said to have occurred at the "Three Buttes" on the plains south of Merced Falls. The total population in the Yosemite section of an animal as stealthy in its habits as the Mountain Lion, is, a-s might be surmised, very difficult to estimate. Placing the number at one to a township (36 square miles), an average figure for an area well stocked with deer, there would be about 12 to 15 lions in our Yosemite section, and 20 to 25 in Yosemite National Park. These figures give the average population at a time when no inten- sive hunting has been done. With a total kill of 31 in three seasons in the Wawona district, the figures given are doubtless high. But these numbers may again be expected if efforts to destroy- the animals be dis- continued. In 1918, and for some years subsequently, there was in the "zoo" in Yosemite Valley a female Mountain Lion which had been captured as a young kitten. Because of the interest which this individual excited among visitors to the Valley and because her record is the only bit of local infor- mation we have concerning the breeding of the Mountain Lion, we give her history and some notes on her habits in detail. On- April 27, 1918, Mr. Jay C. Bruce, now lion hunter for the California Fish and Game Commission, trailed and sliot a female Mountain Lion in her lair in a rocky, brush-covered bluff about 3 miles north of Wawona. The den was among rocks, about 6 feet long and 2 feet wide, and wa.s lined with pine needles. In the den were found 3 dusky spotted kittens, 2 females and a male, wliicli were about the size of cottontail rabbits. Tlifir MOUNTAIN LION 97 eyes were just open and they were judged to be about ten days old. This is the litter mentioned in an article in California Fish and Game (vol. 4, 1918, pp. 152-153). The kittens were taken to Yosemite Valley where one of the females was successfully reared "on the bottle" by Mr. and Mrs. Gabriel Souvelewsky. The authors saw this lioness in May, 1919, when she measured 30 inches from nose to base of tail and 21 inches from base to tip of tail, and weighed, by estimate, about 40 pounds. Her coloration was rich warm brown with small light tawny areas about the face. In a cage adjoining the one occupied by this native lion (Felis o. oregonensis) were two Rocky Moun- tain Lions (Felis o. hippolestes) , from Yellowstone National Park. These were of paler, tawny yellow, coloration with whitish facial areas. They were of such a disagreeable disposition that their cage could be entered only with extreme caution. The Wawona lioness, on the other hand, was quite tame and permitted grown persons and even children to enter her cage freely. The animal was kitten-like in demeanor, romping with the children and chasing a ball in playful fashion. "Whenever it struck, its claws were kept retracted so that a person would feel the impact of only the big furry paw. Once while several people were in the cage the cat jumped on the back of the junior author and the momentum, even at short range, was almost enough to cause him to lose his balance. Even in later years, we have been told, this individual still exhibited a high degree of tameness, although greater caution was exercised in entering her cage. When the kitten sighted persons or animals at a distance it would gaze at them intently, meanwhile moving its big furry tail slowly from side to side. Children in particular seemed to hold its attention. It was surpris- ing to note the distance at which the lioness caught sight of moving objects. This suggested a reason for the fact that Mountain Lions are seldom seen by people — the lions see the people first and quicklj' take themselves off. The captive animal was most active during the morning and evening hours. The mid-day usually found her drowsy. One of our visits was at dusk when the lioness was very active and keenly alert to all that was going on. In this connection it may be recalled that Mule Deer are most active in the early and late hours of the day. The preferred food of the Mountain Lion is deer. Whenever evidence of a reliable nature has been obtained it points to the fact that the deer contributes by far the largest portion of the lion's fare. The current estimate is at least one deer a week for each adult or sub-adult lion. The lion stealthily creeps up within a short distance of the deer, then with a few quick bounds, reaches its quarry and strikes it down. Sometimes a large portion of the deer is eaten, at others, only a small part is taken. The lion may or may not return to its kill for a subsequent meal. Some- 98 ANIMAL LIFE IX THE YOSEMITE times only flesh is eaten, sometimes tlie internal orp:ans are partly ilevoured. In one Avinter the carcasses of 20 deer killed by lions were found in a limited area near Wawona. Four were seen on one day in an area a half-mile square. Assuming that each lion kills on the average one deer a week, a total of 1250 deer a year are killed in the Park. Does have one or two fawns at birth so that about 800 does would be required to provide the annual supply of venison for these lions. As there are deaths among the deer from other causes, the total population of breeding does in the Park must be well above the number mentioned to hold the deer population at its present numbers. The ratio between males and females in the Mule Deer we do not know. An estimate of the total deer population is not possible with the data at hand; but there is no indication of decrease during the past six or seven years. We seem safe in assuming that during this period the lions present have not levied upon the deer population in excess of the deer's recuperative powers. Smaller game is resorted to at times by Mountain Lions. One resident near Smith Creek told of seeing a young lion killing a ground squirrel. An instance of a lion in the Yosemite section feeding upon skunk has already been reported in print by Mr. Donald D. McLean {CaUfornia Fish and Game, vol. 3, 1917, p. 39). The circumstances of capturing this lion were later recounted to the senior author in person by Mr. John L. McLean, as follows : On November 8, 1916, Mr. McLean, senior, was riding on horseback along the road about 8 miles east of Coulterville. His shepherd dog was scouting along the adjacent sidehill through the manzanita and ceanothus brush. At one place there was a strong odor of skunk, and shortly the dog began to bark in tones which indicated that he had treed something. ]Mr. McLean rode to the spot and found up in a golden oak what he at first thought was a bob-cat. Parenthetically, it may be stated that both of the cats {Lynx and Felis) in this region, when seeking safety, climb into golden oaks, probably because the dense foliage of these trees jiffords better shelter than does that of other trees. Presently Mr. McLean saw a long tail hang- ing below a limb and realized that the animal was a Mountain Lion, Promptly he shot it, the rifle ball passing through the lion's neck. The animal "smelled powerfully" of skunk, and later its stomach was found to contain flesh, skin, and black-and-white hair of a striped skunk. This item of food may have been chosen in extremity, though this lion was fat. It measured 5 feet 2 inches in l(>ngth and weighted 371 (.. pounds. WILDCAT 99 California Wildcat. Lynx eremicus californicus Mearns Field characters. — Appearance unique among our wild mammals; size much larger than that of domestic cat; legs longer, but tail much shorter. Head and body 19% to 29 inches (493-735 mm.), tail 4^4 to 6Vi inches (107-160 mm.), ear excluding tuft 21^ to 31/2 inches (66-89 mm.), weight 7% to 19 pounds (3.5-8.6 kg.) [some extra- limital specimens included in measurements]. The smaller extreme applies to females, the larger to males. General coloration above, light reddish brown in summer, gray in winter; under surface of body and inner sides of legs white, spotted or barred with black; ears bla«k-tufted, black at end and base, white on middle. Tracks : Bound, about 2 inches in diameter; sole pad doubly notched behind, not triangular as in coyote. Occurrence. — Common resident on west slope of Sierra jSTevada, chiefly in Upper Sonoran and Transition zones. Recorded from Snelling eastward to Yosemite Valley; altitudinally, ranges to 6500 feet (at head of Nevada Falls). Inhabits brushland, rock slides and timber. Active somewhat by day, as well as at night. Usually solitary. The California Wildcat is a common inhabitant of the hill and mountain country immediately to the west of the Yosemite Valley and is also present in some numbers on the floor of the Valley itself. It is by no means as reclusive an animal as is the Mountain Lion, and is abroad to a considerable extent during the daytime, so that visitors to the region are likely to catch sight of it. The name "bob-cat" is often applied to this species because of its short or bobbed tail, this member being only about one-fourth the length of the head and bodj-. Trappers often refer to large individuals as "lynx-cats," believing that they constitute a species distinct from the ordinary bob-cat or -svildcat, as "granite bucks" are sometimes compared with ordinars^ deer ; but there is only one species of wildcat known in the region. The 'pencil' or tuft of black hairs on the ear, often supposed to be diagnostic of a true (Canada) lynx, is just as regularly present in our wildcat. The coloration of the latter, both as to tone of color and boldness of the black markings, is variable, and, although it has only one molt (this in late summer and fall), its pelage shows considerable seasonal change. In fall and winter the coat is distinctly gray in cast, but with the wearing off of the ends of the over-hairs at the advent of summer, the underlying color, a light reddish brown, comes into view. In Yosemite Valley, and on the trails leading out of the Valley, the tracks of wildcats can often be seen after the snow comes. In December, 1914, we saw numerous tracks on the Yosemite Falls trail, some of which were well above Columbia Point while others led down close to the buildings in the old Presidio. Likewise on the Nevada Falls trail that same season, bob-cat tracks were common in the snow, even to the top of the zig-zags. This fact suggested that the cats were using the man-made trail as a pass between Yosemite and Little Yosemite valleys. During the summer the 100 ANIMAL LIFE IN THE TOSEMITE wildcats are doubtless just as active as in the winter, but they then do more of their hunting in the brush and among the rocks where few or no tracks show. The track of the wildcat is of a rounded shape and on soft earth measures about two inches in diameter. In snow it is somewhat larger, as the toes then tend to spread apart, a characteristic which makes it possible for the cats to hunt over rather soft snow. The hind foot is put exactl}' in the tread of the forefoot of the same side ; therefore the footfall is more silent. On one occasion successive footprints in the snow were about ten inches apart. In some cases each of the cats which followed along the Yosemite trails had walked in the footsteps of his predecessors. In other cases the diiferent individuals, or the same individual at different times, had taken separate courses, for as many as seven parallel lines of tracks were noted in one place. On the Yosemite Falls Trail the wildcats had done much wandering ; their tracks left the trail and went out into the boulder talus, then came back, only to leave again after a few steps; the cats were obviously foraging for the small mammals which dwell in the rock heaps. Where not molested, the wildcat probably hunts nearly as much by day as by night. On at least three occasions members of our party came upon wildcats in the daj'time. On December 9, 1914, a cat was sighted on the lower part of the Yosemite Falls Trail. A second was noted Decem- ber 20, 1914, about 5 p.m., below the mouth of Indian Canon. The third individual was seen one day in October, 1915, at about 4 o'clock in the afternoon, on a roadway below El Portal. The wildcat is a skillful hunter and levies upon a wide variety of the medium-sized birds and mammals. Because of its diurnal activity, the cat naturally includes in its menu a number of diurnal birds such as Valley Quail, which forage on the ground but roost high, out of reach, at night. We found no direct evidence of the cat eating quail in the Yosemite section. On a number of occasions, however, we saw scattered feathers which indicated that a quail had been killed and eaten by some carnivore, whether by a Gray Fox or by a wildcat we could not determine. The numbers of quail captured by cats are probably overestimated by sports- men. At Smith Creek, east of Coulterville, the wildcats during the winter months subsist to a considerable extent upon Western Ko])ins. ^Ir. Donald D. McLean has reported (1919, p. 160) the finding of the remains of no less than six robins in the stomach of one wildcat killed March 10, 1919. As for mammals, the stomach of a wildcat taken in Yosemite Valley about March 18, 1920, contained a considerable amount of Gray Squirrel hair. The cats seen hunting on the boulder talus near Yosemite Falls Trail were presumably after Boyle White-footed Mice and Streator Wood Rats, the two rodents which are common there. WILDCAT 101 Definite information concerning the food of the wildcat is slow in accumulating. The most dependable information is that gained by exam- ining the stomach contents of animals caught by trappers. But in many instances the stomach of a trapped animal is empty or contains nothing but the material used as bait ; had the cat been able to get its regular food it would not have been drawn to the trap. Of three wildcats trapped in Yosemite Valley in March, 1920, the stomach of one was empty, that of the second held only bait, and the third contained the hair of a gray squirrel. The California Wildcat is an adept climber and when tracked with dogs will often take to trees, golden oaks or incense cedars being preferred, probably because the dense foliage of these two affords a greater measure of concealment. Whether the wildcat makes use of its climbing ability to go after birds or mammals which nest or live in trees we do not know. The only local information which we have relative to the breeding of this animal is a statement by Ranger F. S. Townsley to the effect that near Big Meadows about April 20, 1916, he killed a female Avildcat which con- tained 4 embryos. Data at hand from other parts of California indicate that this is an average number. House Mouse. Mus musculus Linnaeus Field characters. — Size small; tail about equal to head and body (pi. 25c); tail nearly naked, scaly; eye small. Head and body 3 to 4 inches (75-106 mm.), tail 3 to 3% inches (74-92 mm.), hind foot % to % inch (17.5-20 mm.), ear from crown i/4 to % inch (11-14 mm.); weight about ^2 ounce (12.7-18.8 grams). Coloration above dark grayish or yellowish brown; under surface uniformly dusky brown, butf or whitish in different individuals; feet dusky. Occurrence. — Not native; came with the white man; now common in and around practically every town or settlement on west slope of Yosemite region, from Snelling and Lagi-ange eastward to Yosemite Valley. Lives about dwellings, barns, and store- houses, and also to a limited extent in grassy places away from buildings. The same House Mouse which is found in our cities is to be found in the western part of the Yosemite region. This alien interloper, so much more aggressive than most of the local rodents, is in firm possession of territory in and about the towns and settlements from the San Joaquin Valley east- ward through the foothills and even into Yosemite Valley. It was not detected about Mono Lake, though it does occur farther to the southeast, at Laws, Inyo County. The general appearance of the House Mouse is familiar to so many people that description is scarcely necessary. It is the standard (pi. 25c) by which other small animals are judged when said to be 'mouse-like.' The tail comprises about half the total length and is scaly in appearance. 102 ANIMAL LIFE IN THE YOSEMITE there being only a verj- few short hairs and no ' pencil ' or tuft at the end. The general coloration is the same over the entire upper surface of the body, a mixed yellowish bro^^^l or grayish brown 'ticked' with black hair endings. The under surface of the House Mouse is ordinarily but little paler than the back; many individuals here in California, however, and especially in the Yosemite region are buff or even white beneath ; the latter color, when present, is never so pure as on the White-footed Mouse, and is not so sharply demarked along the sides. The feet are usually dusky- colored, sometimes pale, but never white. The eye of the House Mouse is small, about half the size of the eye of the Common White-footed Mouse. A striking similarity in external appearance is found between the House Mouse and the Harvest Mouse, the mea.surements, proportions of body and tail, and even the coat color being much alike, particularly with light- bellied specimens of Mus. The appearance of the upper incisor teeth at once separates the two, however. In the Harvest Mouse each of these teeth is marked by a vertical groove ; in the House Mouse, the surface of the tooth is perfectly smooth. The House Mouse is now well established in the Yosemite region and doubtless has been for a great many years. It was probably quite an early arrival, as the foothill districts bordering the Yosemite were among the first areas settled by white people in California ; and this mouse, in America, has closely followed the white settler. Living about houses and barns, it often makes its nest amid household effects, or in bags of grain or bales of hay. When these are carried to a new locality the mice often go also, as stowaways; their spread in this manner is thus passive so far as the mice themselves are concerned. When the goods or other articles are set down in a new location the mice, being in new territory, speedily inerea.se and take possession of their surroundings; and, sooner or later, because of their more aggressive nature, they compel the native small rodents of the neighborhood to give way and finally altogether displace them. But the House Mouse at the lower and middle altitudes is not only about man's habitations. At Snelling and as far into the foothills as El Portal this mouse was found living apart from buildings, in fields and grassy ravines. At the former station specimens were trapped near bluffs fully a mile away from the town. These individuals were living in a really wild state; and this was true in winter (January) as well as in the spring and summer. Their numbers were fully as great as those of the Gambel White-footed Mouse which was present amid the same general surroundings. Besides being an aggressive and adaptable species, this mou.se is also prolific. It breeds practically throughout the year, has rather large broods, and these may follow one another at relatively short intervals. Adults taken at Snelling in January showed signs of breeding activity; while HOUSE MOUSE 103 young, not fully grown, were captured about the barns in Yosemite Valley at the end of December. The broods elsewhere are known to average between 5 and 6. Alexandrine Rat, Rattus rattus alexandrinus ( Geoff roy) Field characters. — The typical 'rat' of household notoriety; tail longer than head and body; tail scaly, with but few short hairs (fig. 12a) ; pelage coarse, with many long overhairs. Head and body 7^ to 8 inches (182-205 mm.), tail 8% to 10 inches (213-250 mm.), hind foot about 1% inches (36-39 mm.), ear from crown about 1 inch (23-26 mm.) ; weight under i^ pound. Upper surface of body plain grayish brown or yellowish brown; under surface uniform dull yellowish; feet dusky, not white. Occurrence. — Not native; now well established, both about settlements and on wild land nearby, at various localities on west side of Sierra Nevada. Eecorded at Snelling, Lagrange, and El Portal. Lives in houses and in thickets and drift debris along banks of rivers. The Alexandrine or 'Roof Rat is one of the few alien species which has become well established in the Yosemite region. Its introduction was wholly unintentional on the part of man, an unwelcome incident in his occupation and settlement of the country. This rat arrived on the California coast when ships first began to visit San Francisco in numbers. From the coast it spread to the interior, aided no doubt by the active boat traffic along the Sacramento and San Joaquin rivers. At first the rat lived exclusively about human habitations, but in later years it has also taken to living in the wild, and is now so well established out-of-doors in many locations that a person unacquainted with its history would be likely to consider it a native species. The Roof Rat is considered to be only a color variety of the Black Rat. It has the long slender tail of the latter, a character which at once dis- tinguishes it from the Norway or Brown Rat. Specimens of the Norway Rat have not as yet been forthcoming from the Yosemite region. The Roof Rat is much more of a climber than the Norway Rat. About maritime ports the former predominates on shipboard. On shore it takes to the roofs and walls of buildings, while the Norway or 'sewer' rat lives in cellars and basements. But along the Sacramento and San Joaquin rivers and their principal tributaries the Roof Rat has taken to living in the piles of drift material and brushy thickets along the river banks. This departure from man-made shelters is made possible by the relatively mild winter of central California, which is closely similar to the winter of the original home of the Roof Rat, in the countries of Asia Minor. Along the coast in central California the Brown Rat has largely supplanted the Roof Rat, and possibly may do so eventually in the interior. 104 ASIMAL LIFE IS THE YOSEMITE At Snelling, in January, 1915, a number of roof rats were taken in piles of drift and thickets along the Mercetl River. There were old deserted nests of the Streator Wood Rat in the same locality and the suggestion presented was that ])0ssibly the alien, with similar associational predilec- tions, had driven out the native species. Along the Tuolumne River below Lagrange the roof rats had made numerous pathways which were at first mistaken for large runs of meadow mice. At El Portal two of the rats were captured November 23 and 25, 1914, in the upper stories of the large hotel building then there. The species is unknown at Coulterville, according to Mr. Donald D. McLean, though House Mice are present there. The mice are transported readily in bales of hay hauled on wagons, but the rats require larger vehicles such as river boats or railroad cars. Common White-footed Mice. Peromyscus maniculatus (Wagner)* Field characters. — Size slightly greater thau that of House Mouse; ear larger and tail shorter (pi. 25b and text fig. lOo) ; tail distinctly less than length of head and body, not scaly in apprarance. (For measurements, see footnote 8.) General color above yellowish brown (blue-gray in young) ; below pure white, sharply set oflf from color of upper surface; tail bicolor, that is, white, with a dark stripe above; feet pure white. Occurrence. — Abundant resident throughout the entire Yosemite section from the San Joaquin plains at Snelling eastward without interruption across the mountains to Mono Mills; range upward to at least 10,800 feet.s Inhabit every sort of cover from stream margins to the dryest slopes and moat barren rock slides. Nocturnal. The Common White-footed Mice are without any doubt the most abundant mammals in the Yosemite section. Indeed, it is not unlikely that the total population of this one species nearly or quite equals that of all the other mammals in the region together. Its numbers do vary somewhat according to place and season, but it is always present, and in some places it may be said to fairly swarm. In whatever locality we placed our traps this kind of mouse was sure to be caught. In places these mice simply have to be 'trapped out' before representatives of other species can be 8 Two subspecies of these mice occur in the Yosemite section, one on the west slope, the other on the east side of the mountains, the two intergrading over the crest of the Sierras. Gambel White-footed Mouse, Pcromy.icns inaniciilatu. ounce (12.8-21.1 grams); .sonorieusi.'s : head and body HJ/j to 4% inches (H.'{-1()6 mm.3, tail 2%-'A inches (55-75 mm.), hind foot about 'f, inch (19-21 mm.), ear from crown % inch (15-17 mm.), weight % ounce (10.1» 2S.5 grams). WHITE-FOOTED MICE 105 obtained. Yet White-footed Mice are practically never seen by daylight, for they are as strictly nocturnal as are bats. Except for the fact that it does most of its foraging on or close to the ground there is scarcely any limitation to the range of this mouse. It frequents the very edge of running water, thickets and grass clumps on the banks of streams, the runs of meadow mice in damp grasslands, the sides of dry gullies, mixed growths of brush plants on the hill slopes, old buildings, logs and boulders in the forest, and heaps of slide rock on the mountain sides. On one occasion some mice of this species were found living in burrows on altogether open ground, a place where only kangaroo rats were expected to occur. Fig. 10. Showing differences in ear between the four species of White-footed Mice found in the Yosemite section, (a) Gambel (Common) White-footed Mouse; (6) Boyle White-footed Mouse; (c) Parasitic White-footed Mouse; (d) Gilbert White-footed Mouse. For nesting places and daytime retreats "White-footed Mice make use of any available cover, such as is afforded by crevices or holes in rocks, hollows in trees or in logs, or holes in the ground. Often they use burrows made by other rodents, while in some cases it seems likely that they do a certain amount of excavating themselves. Despite its great numbers this mouse does not leave any very obvious indications of its presence. Its small black droppings are the only regular and definite evidences to be found. Nothing distinctive pertaining to its nest, or route of travel, or choice of food, is left as a clue, as is the case 10(3 AMM.IL LIFE I\ THE YOSEMITE with most other rodents. It seems to be the most adaptable of all the small mammals, fitting into types of habitat unused by any of the more specialized mammals and venturing? into the special territory of these which may not be fully occupied. AVith this flexible nature it might be expected that the White-footed Mouse could and would become a pest about human habitations, but there has been no development in this direction. The species does hold the la.st line of defense for the wild species, living, as it does, about cabins and barns in newly settled territory; but it quickly retreats upon the arrival of that more aggressive alien, the House Mouse. The Common White-footed Mouse is somewhat larger, differently pro- portioned, and differently colored than the well-known House Mouse. (Compare pi. 25b and c.) The average weight of tlie Gambel ]\Iouse is 0.62 ounce (17.5 grams), and of the Sonora Mouse, 0.86 ounce (24.5 grams), while that of the House Mouse is 0.58 ounce (16.4 grams). The tail of the Common White-footed Mouse is less in length than its head and body; in the House Mouse it is about equal. The ear of the Common White-footed Mouse averages larger, % inch (16 mm.), compared with a])0ut V12 i"ch (13.5 mm.) in the House Mouse. The White-footed Mouse is conspicuously white on its under surface, this white extending to the under side of the tail and including the entire feet. The House Mouse, on the other hand, is dingy gray underneath, wath no sharp line of demarcation along the sides ; the tail is monochrome, not bicolor ; and the feet are dusky. The tail of the White-footed is well haired (though the hairs are very short), not nearly bare and scaly, as is that of the House Mouse, It should be stated here that there are no less than four species of M-hite-footed mice in the Yosemite section, and in certain places on the west slope of the mountains all four are to be found in close proximity to one another. (See fig. 11.) All four of the species bear a general resemblance to each other and two of them (the Boyle and True) are enough alike to make it difficult to identify individuals. The Common White-footed Mouse {Peromyscus maniculaius with subspecies), the sub- ject of the present chapter, is the smallest of the four (see fig. 10 and pi. 25). Its tail is shorter than the head and body, 3 inches or less (75 mm.), and is distinctly bicolor, that is, pure white with a dark stripe along the top. The hind foot is shortest, measuring % to % of an ineh (18-21 mm.) ; its ear is smallest, measuring i^ to % of an ineh (13-17 mm.). The Boyle White-footed Mouse (Peromyscus hoyJii) is the next in point of size, and can be recognized further by the combination of medium sized hind foot (21 to 23 mm.) and medium sized ear (from crown, 17 to 20 mm.). In this and the following two species the tail is distinctly longer than that of the Common White-footed Mouse, equaling or exceeding the combined length of the animal's head and body. WHITE-FOOTED MICE 107 The True and Gilbert white-footed mice (which are subspecies of the one species, Peromyscus truei) have much larger ears, measuring 20 to 26 mm. ; and the hind feet average longer, measuring 22 to 25 mm. Also the pelage is longer (hair on rump 11 mm., instead of 7 or 8 mm. as on the Boyle Mouse). The Gambel and Sonora Mice are short-haired, while the Parasitic is long-haired. The fourth species in the series, the Parasitic White-footed Mouse (Peromyscus californicus) , is decidedly larger than any of the other three ; its hind foot is longer, measuring 25 to 28 mm., but its ear is no larger than that of the True and Gilbert, since it measures 21 to 23 mm. above crown of head. (See accounts of each of the species for detailed measure- ments.) The relative size of each of the four species of white-footed mice may be judged from the following weights, which are averages obtained from selected adult specimens: Peromyscus maniculatus, 21.0 grams; P. hoylii, 26.5; P. truei, 29.5; P. californicus, 45.0. Fig. 11. Cross-section of the Sierra Nevada through the Yosemite region showing zonal and altitudinal ranges of White-footed Mice (genus Peromyscus). The white-footed mice are practically all under cover through the daylight hours. Occasionally a few are trapped during the day, especially when traps are set in shaded places; but they are by no means as active then as are the meadow mice. Their 'day' comes at night. As soon as the dusk has claimed all but the nearest of objects, these mice begin to venture abroad. Most of their running about is done during the earlier hours of the night, but some are still abroad when the "Wood Pewees utter their first calls shortly before the break of day. The camper who goes early into his sleeping bag and there listens for the night sounds is likely to hear little rustlings among the leaves, indicat- ing that the white-foots are abroad. One evening in mid-May at Hazel Green, one of us happened to put his sleeping bag close to the base of a large tree beneath which there was an accumulation of leafy debris. Soon after dark a Common White-footed Mouse began exploring the neighbor- hood. For some time it stayed within a radius of 6 or 8 feet, rustling among the leaves and occasionally making larger shifts of position. These 108 ANIMAL LIFE IN THE YOSEMITE were accomplished by swift nms; the rapid patter of small feet would be followed by several seconds of quiet while the mouse took account of its new surroundingrs. About this time the moon came up and the mouse could be seen clearly in the bright light. Whenever the observer moved, the mouse would scamper into some hiding place; but its fright was of very short duration and it would soon reappear. That the Common White-footed Moase does on occasion range higher than the ground is indicated by the fact that several individuals were trapped on pantry shelves up to six feet above the floor in a house in Yosemite Valley, and another individual was caught eight feet above the ground on top of a prostrate tree in a windfall at Tuolumne ]\Ieadows. Practically all our traps were set on the ground, so we are unable to state the extent to which these mice may climb. The animals sometimes venture well out from shelter ; individuals were taken on open ground as much as 20 feet away from cover of any sort. Most of those trapped, however, were obtained close to or under logs, rocks, or brush, where the majority of our traps were set. At Snelling an adult and a juvenile mouse were caught together in the same trap, this incident suggesting that young individuals may forage for a time in company with their parents. The species is not colonial, in any definite sense of the term ; although it occurs locally in considerable numbers, the adult individuals are, as a rule, intolerant of one another's presence. It is not known with certainty that the Common White-footed Mice hibernate. There is even good evidence to the contrary. In the winter months their tracks are often to be seen in Yosemite Valley, on the surface of the snow. Individuals were trapped in December in dead grass and leaves in sheltered places. Here, it seemed likely, they had been running about among the bases of grass stems beneath the snow mantle. The breeding season is of long duration and each female very probably bears more than one litter a year. Females with embryos were taken from May 13 until October 24, and evidence, in the form of blue-pelaged juvenals or sexually active males, suggested that, in the lower altitudes at least, the species was breeding practically throughout the year. The number of young to a litter ranges from 3 to 7, avera^ring 5. Of 38 sets of embryos examined, in two ca.ses there were 3, in eight cases 4, in thirteen 5, in thirteen others 6, and in two cases there were 7. The young come quickly to maturity and some of them undoubtedly breed during the same sea.son in which they are born. Thus within one favorable season, when all of the offspring would be able to find sufficient food of a suitable nature, the numbers of these mice might increase very greatly. WHITE-FOOTED MICE 109 A maximum concentration of Sonora White-footed Mice was encoun- tered at Mono Mills in 1916. A line of 30 traps about one-half mile in length was set on the ground in the sagebrush among Jeffrey pines near the mill. On the night of June 6, 10 Peromyscus wi. soncriensis and 6 other rodents were caught in this one trap-line. During the day of the seventh 8 chipmunks and 2 Golden-mantled Ground Squirrels were obtained. The night of June 7, 21 Peromyscus and one pocket mouse were trapped; the night of the eighth, 20 Peromyscus and two pocket mice; and the night of the tenth, 15 Peromyscus and 1 Kangaroo Rat. Then the line was taken up. The collector's own footprints made as he visited his traps at night- fall to bait and re-set them would in places by morning be obliterated by the multitude of tiny tracks made during the night. Many of the mice in the traps were partially eaten, probably by others of their own species. Food in general seemed scarce. The suggestion presents itself that an unusually large population had resulted from exceptionally favorable conditions, including abundant food during a preceding period ; and because of the discontinuance of these favoring conditions, the mice were on the verge of starvation just at the time the member of our party started trapping. The potential powers for the expansion of mouse population, as based upon the figures for rate of breeding given above, are enormous, possibly twenty-fold in a single year. A sequence of favoring conditions may on occasion bring about the full realization of this potentiality; but eventually there will be a return to normal numbers. Many of the Sonora White-footed Mice trapped at Williams Butte in the fall of 1915 were sorely afflicted with huge rabbit-fiy bots on the back or flank. An immature male, trapped September 22, 1915, had one of these maggots imbedded beneath the skin on one flank and opening toward the ankle. The mouse weighed 14 grams, and the fly larva 1.3 grams — nearly one-tenth the weight of the host! In Yosemite Valley when the melting snows at higher levels cause a rise of water in the Merced River, the Valley meadows are flooded and the non-aquatic animals which live there are forced, at least temporarily, to seek higher ground. The white-footed mice then move up-slope, invad- ing, en route, the gardens and even the houses of the people living in the Valley. One householder told us that on one particular night, during such an invasion, there were fully 20 of these mice running about the rooms in her house. After a few days the white-foots leave the neighborhood of the houses and seek their more natural retreats. 110 ANIMAL LIFE IN THE TOSEMITE Boyle White-footed Mouse. Peromyscus boylii boylii (Baird) Field characters. — Size more than half again that of House Mouse, about one-third larger than Common White-footed Mouse (see pi. 25a) ; tail usually slightly longer than head and body; hind foot and ear (fig. 10b) both of moderate size. Head and body 3V^ to 4 inches (87-100 mm.), tail 3% to 4% inches (95-110 mm.), hind foot about % inch (21-23 mm.), ear from crown about % inch (17-20 mm.); weight % to 1V4 ounces (22.6-34.4 grams). General coloration above dark brown (bluish gray in Juvenal), this color sharply set off along sides from pure white of under surface of body; feet white. Occurrence. — Common resident on west flank of Sierra Nevada, chiefly in Upper Sonoran and Transition zones, but occasionally at higher stations. Recorded regularly from Pleasant Valley eastward to walls of Yosemite Valley and sparingly at Porcupine Flat and Glen Aulin. Inhabits vicinity of rocks and brush on sides of ravines and canons, less often grassy places, but as a rule not far from water. Nocturnal. The Boyle White-footed Mouse is second in point of size, numbers, and extent of range among the four species of white-footed mice in the Yosemite region. It is larger than the Common White-foot but smaller than the Gilbert Mouse, and it also stands between these two in relative numbers as is revealed by our extensive trapping. The range of the Boyle Mouse lies entirely on the western drainage of the Sierras; the species has no counterpart on the eastern side of the mountains in this latitude. The local range embraces much of the territory between the altitudes of 600 and 6000 feet. A variety of situations is occupied by this mouse, though it is rather more restricted in this respect than is the Common White-foot. Some Boyle mice were captured on brushy and rocky stream banks, others (at El Portal) were in sandy 'second bottom' land under wild grapevines, still others under brush plants on hillsides, and many were obtained at El Portal and in Yosemite Valley, amid rocks on talus slopes covered with golden oaks. In Yosemite Valley this species is a regular inliabitant of the rock heaps along the Valley walls, but it seldom occurs out on the floor of the Valley. One factor which seems to be constant in its requirements is proximity to water, not necessarily very close at hand but where it can be reached during the animal's nightly foraging. The Boyle Mouse is the best climber among the four local species of white-footed mice. One was trapped on a shelf of rock 10 fret above the bottom of a canon; on this rock were many droppings indicating that mice had run about on it upon various occasions. Elscwiiere Boyle Mice have been seen climbing about in trees. Among the numerous specimens trapped in Yosemite Valley were many having the oars variously notched and otlicrwiso mutilated; also individuals with tails more or less bobbed. These things ])()int 1o a certain trait known WHITE-FOOTED MICE 111 to manifest itself among- captive mice, namely, propensity toward violent combat between adults, especially during the periods when they are sex- ually active. Definite information concerning the breeding season of the Boyle Mouse consists of records of embryos in 7 females and the capture of a number of blue-pelaged juvenal animals. The females with embryos were taken from May 19 to June 7 (1915), and held from 2 to 5 embryos, averaging about 3. But blue-pelaged young were taken as early as June 7, indicating birth about a month earlier. Even as late as December 2, blue-coated young were trapped, a fact which indicates that some litters may be born in late October or even early November. Big-eared White-footed Mice. Peromyscus truei (Shufeldt)^ Field characters. — Size about twice that of House Mouse, and somewhat greater than Common White-footed Mouse; tail about equal to head and body; ears large (20 mm. or over). (See fig. lOd.) Pelage long and dense; tail well haired, with a slight 'pencil' at tip. General coloration above dark brown, sharply set off from pure white of under surface; feet white. Occurrence. — ^Resident on west slope of Sierra Nevada, chiefly in Upper Sonoran Zone. Recorded from Pleasant Valley eastward to 6 miles ea.st of Coulterville and to El Portal (subspecies gilherti). Also east of Sierra Nevada on Williams Butte (subspecies truei).^ Lives about rocks and brush. Nocturnal. White-footed mice of the big-eared or triiei group are present on both slopes of the Sierra Nevada but never in as large numbers or so widely distributed as the common species (maniculatus) . The range of this species on the west slope lies chiefly in the Upper Sonoran Zone ; on the east side it was found in the belt of piilon pines. The Gilbert Mice of the west side were found on the ground in brushy places or under pines and other trees near the chaparral, and on one occasion about a deserted building. The True Mice of the east slope were mostly taken in or near rocks, though this species is not necessarily a rock dweller. 9 Two slightly differing subspecies of this group occur on the opposite slopes of the Sierra Nevada. Their ranges do not touch at any point in the Yosemite region, but they do come together at other localities to the south, and intergradation takes place there. Hence the two are considered as subspecies of one species. Gilbert White-footed Mouse, Peromyscus truei gilherti (Allen). The form common through much of California west of the Sierra Nevada. It was found locally from Pleas- ant Valley eastward to Smith Creek (6 miles east of Coulterville) and to El Portal. True White-footed Mouse, Peromyscus truei truei (Shufeldt). A slightly paler, more silky haired subspecies, which occupies a wide range of territory east of the Sierra Nevada. It was recorded by us on the south slope of Williams Butte in small numbers. Measurements.— Gilherti: head and body 31/^ to 41/3 inches (88-110 mm.), tail 3% to 41/3 inches (94-111 mm.), hind foot % to 1 inch (23-25 mm.), ear from crown % to 1 inch (20-26 mm.), weight % to 1% ounces (23.5-41 grams). Truei: head and body 3% to 4 inches (91-100 mm.), tail 3% to 4 inches (92-100 mm.), hind foot about % inch (22.5-24 mm.), ear from crown % to 1 inch (20-24 mm.), weight 7/10 to iVe ounces (20.6-33.0 grams). 112 AXIMAL LIFE IS THE YOSEMITE At Blacks Creek, west of Coulterville, on the nights of May 10 and 11. 1919, a line of 37 traps, set through a mixed stand of brush plants on a shaly hillside, produced 7 and 8 Gilbert Mice. They seemed to be the only mice of the Avhite-footed group (Peromyscus) present there. They were evidently finding daytime shelter in heaps of shale at the mouths of old prospect holes, in weathered outcrops of the same rock, and in tangles of dead brush. At El Portal and Pleasant Valley the numbers of this species were less than those of the Gambel and Boyle white-footed mice though greater than those of the Parasitic Mouse. No conspicuous differences in habitat were evident between these several species and it yet remains to work out their ecology. A postulate in animal distribution is that no two species can permanently occupy exactlj^ the same niche in nature, and the evidence in many cases is convincing. But with the several species of white-footed mice there is still much to be explained in this connection. One of the Gilbert Mice obtained at Blacks Creek was caught only by the tail and as it seemed uninjured it was carried to a pool in the creek bed to test its swimming abilities. The instant it touched the w-ater the mouse began to swim, using all four feet, and soon gained the bank. It walked slowly up the rocks, but when the observer made an attempt to follow, the mouse put on speed, ran quickly up the hill, and was lost to view in the brush. The breeding season of this mouse is not knoAvn with any certainty. Between May 25 and June 3, 1915, 5 females, each containing 3 or 4 em- bryos, were trapped. Blue-pelaged juvenals were obtained at about the same time, and suckling females were captured in July. These meager data point to a breeding season three months in extent, Avith the probability that it is of somewhat longer duration. Parasitic White-footed Mouse Peromyscus calif ornicus calif ornicus (Gambel) Field characters. — Size more than twice that of Houso Mouse or of Common White- footed Mouse; ear very large (see fig. 10c) ; tail longer than head and body. Head and body 4 to 5 inches (99-123 mm.), tail 4% to 5^$ inches (117-136 mm.), hind foot 1 to 1% inches (25-28 mm.), ear from crown % to % inch (21-23 mm.); weight lVj-1% ounces (41. .'5-48. 4 grams). General coloration dusky brown on upper surface, sharply set off from pure white of under surface; feet white. Occurrence. — Kesident in Upper Sonoran Zone on west flank of Sierra Nevada where recorded at Pleasant Valley and El Portal. Lives on hillsides covered with oaks and chaj)arral; sometimes about deserted nests of Streator Wood Kat. Solitary. The Parasilie White-fooled Mouse is tlu> largest of our four species of white-footed mice; indeed, in jjoint of size it ai)proaehes an iinjnalur«' wood rat. The name 'parasitic' was applied to this mouse because it is WHITE-FOOTED MICE 113 often found about nests of the wood rat and for a time was believed to live habitually with that species. Now it is known that the Parasitic White-footed Mouse, while using deserted wood rat nests to some extent, is also to be found in other sorts of shelter. Its particular niche in the fauna of the foothill oak-chaparral belt is not surely known, though this species does not seem to be greatly different in habits from the Boyle and Oilbert mice. The present species is the least common of our white-footed mice. Only 6 specimens were obtained in all the trapping which we did within its range, while at the same time the other white-footed mice were obtained literally by the score. In one instance a trapped Parasitic Mouse was found to have its stomach enormously distended with some finely chewed material that smelled like oak mast. The stomach with contents weighed 9.7 grams, which was one- fifth the total weight of the mouse. Short-tailed Grasshopper Mouse Onychomys leucogaster brevicaudus Merriam Field characters. — Size nearly twice that of House Mouse; tail very short, about one-third length of head and body, and clothed evenly and densely with very short hairs ; claws on front feet long and sharp. Head and body about 4 inches (85-105 mm.), tail about 11/2 inches (32-40 mm.), hind foot % inch (18-22 mm.), ear % inch (13-16 mm.) ; Aveight nearly 1 ounce (23-30 grams) [measurements and weights from eastern Mono County specimens]. Coloration sharply bicolor; upper surface pale sandy brown (light gray in young); under surface of body, and legs and feet, pure white; a large white spot at forward base of each ear. Occurrence. — Eesident in Great Basin region east of Sierra Nevada. Eecorded in our Yosemite section only on the Farringtou Eanch near Williams Butte. Lives on ground beneath sagebrush. Very little is known of the habits of the Short-tailed Grasshopper Mouse. Our own experience with it in the Yosemite section was limited to the capture of a single individual, September 23, 1915, in an oat-baited trap set beneath a small sagebush on the flat south of Williams Butte. This mouse was caught on exactly the same sort of ground as the plentiful Sonora White-footed Mouse, which species the Short-tailed Grasshopper Mouse resembles in a general way. There are pronounced differences, however, in that the latter species has a conspicuously shorter tail, rather smaller ears with a white spot at forward base, and front feet which are armed with longer and sharper claws. The grasshopper mice, as the name suggests, have a well-known predi- lection for feeding extensively upon insects. Furthermore, examples cap- tured alive elsewhere and introduced into a cage with Harvest Mice and White-footed Mice promptly killed and proceeded to eat those mammals. 114 JMMAL LIFE IX THE YOSEMITE Long-tailed Harvest Mouse Reithrodontomys megalotis longicauda (Baird) Field characters. — Size and general form of House Mouse; each upper incisor tooth with a single groove down its front surface; tail about equal to head and body, very scantily haired. Head and body 2% to 3'^ inches (61-83 nun.), tail 2^2 to 3% inches (63-79 mm.), hind foot about % inch (16-18 mm.), ear about ^t inch (11-15 mm.); weight about % ounce (8.5-12.5 grams). Coloration above bufify and black mixed in fine pattern, blending along sides with dull white of under surface; ear clothed with very short tavmy-colored hairs. Occurrence. — Common resident in Lower and Upper Sonoran zones on west slope of Sierra Nevada. Eecorded from Snelling and Lagrange eastward to Sweetwater Creek, to El Portal, and to Smith Creek, 6 miles east of Coulterville. Lives chiefly in grassland, occasionally on brush-covered slopes, if these be shaded and damp or near water. The Long-tailed Harvest Mouse is a small dun-colored animal, of retir- ing habits, that to the casual eye is simply a field mouse. It dwells in grasslands, among weeds along fences and irrigation ditches, and in similar places. Unlike the meadow mice it leaves no reliable indication of its presence and so must be specially sought for, else it will escape observation entirely. Externally, the harvest mouse has much the appearance of the House Mouse, the size of the head and body and the relative length of the tail being about the same in the two. In the harvest mouse, the pelage is longer and silkier, and the tail is less conspicuously scaly, than in the House Mouse. The ear is clothed with short tawny hairs. Perhaps the best character for surely distinguishing these two species pertains to the upper incisor teeth. In the harvest mouse the front of each tooth has a conspicuous groove running the full length, the effect of which is to suggest that the mouse has four rather than two upper incisors. The harvest mouse is much smaller than even the smallest of the local white-footed mice and so is not likely to be confused with any of that group at all. Lack of fur-lined cheek pouches distinguishes it from the pocket mice. For practically all of the harvest mice caught in the Yosemite section we have records of the circumstances of capture and so are able to state satisfactorily the local haunts of the species. The animals inhabit a con- siderable variety of situations ranging from the immediate vicinity of water to dryish rocky and brushy hillsides. By far the greater number, however, were captured in rather damp grassy places. At Snelling, cat-tails, gra.ss, wild oats, horeliound, and blackberry were growing at points of capture. Marshy places, meadow, dry ravine bottoms, rolling lands, bottoms of small gulches, grain fields, and weed growths along fences were all places which the species frequented. At Smith Creek, east of Coulterville, and at El HARVEST MOUSE 115 Portal, a few harvest mice were taken in the runways of meadow mice. And at the last-named place some harvest mice were obtained amid rocks on a steep greasewood-covered hillside which was several hundred feet higher than the grasslands bordering the river, and as far removed from any stream. In all instances our specimens were trapped on the ground. Harvest mice are said sometimes to use birds ' nests above ground as founda- tions for their own nests, but we found no evidence on this point. The total population of this species must be great. AVe have no means of stating it in relation to any given area occupied, and furthermore the density of the population varies greatly from place to place. But in favor- able situations, especially amid grassy growths, our trap lines produced harvest mice as long as the lines remained in place. It was no uncommon thing to obtain along with other small rodents 5 or 6 individuals of this species in one night, from 40 to 60 traps set over a half-mile of favorable country. At Snelling, in January and May, the males numbered 20 and the females 15, in the cases where sex was recorded. A preponderance of males in January, when breeding activity was commencing, might be expected ; for males then range more widely than females and hence are likely to be caught more commonly in traps. The sexes in the Harvest Mouse are in reality probably about equal. The breeding season for the Long-tailed Harvest Mouse is a long one. As just indicated, males began to show breeding activity during the first week of January. By May, young of nearly adult size were abroad in small numbers at Pleasant Valley, and females with embryos were common. The number of embryos ranged from 3 to 6, averaging clovse to 4. A female with large embryos was taken at Smith Creek on July 13, 1920. The absence of trapping records from August to October leaves doubt as to how late the breeding season continues, but it seems likely, from informa- tion gained elsewhere, that it continues until some time in the fall. At El Portal in December, where numbers were taken, no breeding individuals were noted. A species which produces four young at a birth, and in which the young mature rapidly and probably breed late in the season in which they are bom, has the potentiality of a rapid numerical increase within a single season. Despite this ability to increase its numbers, the Long-tailed Harvest Mouse has never been found to play any economic role, either harmful or otherwise, for it retires before cultivation and occupies marginal areas only. 116 ANIMAL LIFE IN THE YOSEMITE Streator Wood Rat. Neotoma fuscipes streatori Merriam Field characters. — Form and size about those of House Rat, but tail shorter than head and body (fig. 13); tail round, closely haired, not bushy (fig. 12i); pelage soft and smooth; ear rather large, rounded. Head and body 714 to 8V4 inches (183-209 mm.), tail 6% to TV2 inches (165-191 mm.), hind foot about 1^ inches (35-38 mm.), ear from crown 1 to IVi inches (24-32 ram.), weight 7^4 to 8% ounces (206-247 grams). Coloration brownish gray with a general overlay of black hair tippings; whole under surface of body, under side of tail, and upper surface of feet, white. Workings. — Nests or 'houses,' 2 to 3 feet high, conical in shape, composed of twigs, leaves, chunks of wood, etc.; placed on ground beneath brush plants or trees, or, less often, on horizontal branches of oak trees at height of several feet from ground. Drop- pings: Cylindrical, about % inch long and % inch in diameter, scattered in and about nest, or at intervals along runways. Occurrence. — Common resident chiefly in Upper Sonoran Zone and lower part of Tran- sition Zone, on west slope of Sierra Nevada. Recorded from Snelling and Pleasant Valley eastward to floor of Yoseniite Valley. Lives in mixed stands of trees and brush, occasion- ally among rocks. Chiefly nocturnal. The Streator Wood Rat is well known to residents of the foothill country of east-central California. The animal itself is seldom seen, but evidence of its presence in the form of large nests or 'houses' is to be observed in many places. This animal is often referred to as 'pack rat' or 'trade rat' by rea.son of its propensity for carrying articles from place to place in and about cabins or camping places. The Streator Wood Rat is close to the house rat in size, the length of body and the weight being about the same in the two; but the wood rat's tail is shorter than its head and body, while the reverse is true of the roof rat. The pelage of the wood rat is rather short, witli no conspicuous coarse over-hairs; it is den.se and even, and feels soft to Fig. 12. Tiiils of (a) Alexandrine thetouch. The coloration above varics Roof Rat, {})) Streator Wood Rat, and f,.,,,,, ),lm; „p.,y ;„ Oj^ younger aili- (c) Gray Hushy tailed Wood Rat. One *^ ' . ' half natural size. iiials to saTidv browii in adults. Very WOOD SATS 117 large males become suffused with reddish or huffy hrown, particularly on the sides of the body. On the whole under surface of the body and tail at all ages the fur is pure white. Although streatori is grouped with the brown-footed wood rats, its feet are pure white, as is also the lower half of its tail. The tail of the Streator Wood Rat is well haired and hence quite different in appearance from the scaly tail of the roof rat ; but the hairs on the tail of streatori are short and closely laid, with no long hairs on the sides of the tail as in the Bushy-tailed Wood Rat. (See figs. 12&, 13.) Pig. 13. Streator Wood Rat. Photographed from fresh specimen trapped near foot of Yosemite Palls trail in Yosemite Valley, November 22, 1915. About % natural size. The Streator Wood Rats are active chiefly by night, so that sight of one is seldom obtained. Most of our information relating to the rats them- selves was gained by setting traps baited with rolled oats near nests or other places which showed signs of recent occupancy by the animals. The individuals taken for specimens were all trapped during the night-time. Only three of the animals were noted abroad during the daytime and on each occasion the rat was in view for but a few seconds. At El Portal, in early December, one was seen to run into a brush pile on the hill above the river ; near Cascades in November a wood rat appeared while one of our party was 'squeaking' at a Winter Wren; and near Coulterville an adult wood rat was frightened from its nest while one of our party was dismantling the structure. The 'round-tailed' wood rats are active throughout the year, so far as we know; trapping at any season is likely to produce specimens. In Yosemite Valley tracks of the Streator Wood Raf were seen in snow on the Yosemite Falls Trail on December 9 (1914). In midwinter, when snow covers the exterior of t"he rock slides on the Valley walls, the wood rats are able to run about in comfort and safety in the spaces between and beneath the granite blocks. 118 ANIMAL LIFE IX THE YO SEMITE Usually the -wood rats obtained for specimens were trapped close to nests, but in one instance an immature individual was taken in a trap set on the ground beneath chaparral in a place where no evidence of wood rat activity was to be seen. At El Portal there were indications that the wood rats were using the trails made by the brush rabbits through and beneath the greasewood chaparral. These rats have regular paths or trails of their own, especially along the walls of narrow ravines. These paths are kept more or less bare of leaves, evidently by the frequent passage of the animals over them. At Dudley the rail fences through dense chaparral were being used regularly as highways ; the lower rails were chosen rather than the uppermost one, doubtless on the principle of "safety first." At Kinsley, droppings of wood rats were found in the farthest recesses of a cave some 50 feet from its entrance. Animals living there would have to seek territory for foraging altogether outside the cave. The most conspicuous feature in the life history of the Streator Wood Rat is its propensity to build houses. These structures are usually conical in shape and measure from 18 inches to 3 feet in height, having the same or a slightly greater diameter at base. A majority of the houses are built on the ground, among or beside brush plants, but seldom far away from such trees as live oaks and willows. Sometimes the nests are placed on horizontal branches in oak trees at heights of as much as 15 feet above the ground. Less often the animals live among the rocks, and then the shape of the house or nest is accommodated to the crevices available between adjacent slabs or boulders. Now and then the structure is heaped around a downed tree, as described below; and in one case a nest was found in the hollow trunk of a living black oak. Tlie usual wood rat nest is only a pile of various sorts of material of such kinds as can be accumulated from the near vicinity of the site. Within, there is a nest chamber of varying size and proportions. The houses some- times have underground retreats or passageways, as through a hollow tree root, so that in time of danger the wood rat can escape from the nest without appearing on the surface of the ground until it is some distance away. Entering into the composition of different houses in the Yosemite foothills we found the following materials: twigs and green cuttings of Ccanothus cuncahts, C. intcgcrrimus, buckeye, live oak, golden oak, yellow pine, and willow, reed stalks, cones of yellow pine, chunks of decayed wood, and, in one case, stones, each weighing several ounces. On a digger-pine-covered hillside which had been burned over within a year, near the McCarthy ranch, 3 miles east of Coulterville, a house of the Streator Wood Rat was found and studied, June 2, 1915. (See fig. 14.) This structure had been built on and i)ar11y within a rotten log which lay on the ground. There was a that eh of dry sticks and jiieees of bark WOOD BATS 119 from the digger pine, and this covering seemed to have protected the interior of the nest effectively against moisture. At one end of the log was an entrance to the interior and here was accumulated a mass of drop- pings and other debris which the animals had removed from within the house. Inside the house, partly or completely inside the log, were no less than four beds or nests proper; only one of these was occupied when the place was examined. The beds were composed of shredded wood, dry twigs and grass stems, and some green leaves. In one place a quantity of fresh young leaves of the golden oak was found. Three holes led out from the main interior cavity of the house, one of these going down lengthwise of the log, while the two others went into the ground. dump Fig. 14. Sketch showing interior arrangement of nesting quarters of a Streator Wood Eat in a hollow log. Locality, three miles east of Coulter\-ille, June 2, 1915. In one of the beds a very young wood rat was found ; and an adult animal ran out of the same nest as the place was opened up. No other wood rats were seen nor had any been trapped adjacent to this log during the few days preceding, so it seems likely that the place was tenanted by just the two. Part of the interior of the nest contained a mouldy mass of old droppings and bits of twigs, and fresher droppings were found about the beds. The animals seem to exercise none of the precautions for clean- liness observable in some rodents, for example, pocket gophers. The damp earth beneath one nest abounded in fleas, though none of these pests were to be seen on the young wood rat which was found in this nest. The breeding season of the Streator Wood Rat, to judge from the capture of strictly juvenile specimens, includes most of the warm months of the year. Thus, a juvenile animal trapped at Pleasant Valley on May 19 (1915) points to an early commencement of breeding activity, possibly in March; whereas an immature specimen captured on Novem- ber 24 (1915) near Cascades could not have been born earlier than September. Trapping in May and June, however, gave evidence that the greatest amount of breeding activity occurred at about that season. Most of the females taken then were suckling young, and two nests examined each held a single young animal. A female collected May 24 120 ASIMAL LIFE IS THE YOSEMITE at Pleasant Valley contained one embryo, and another obtained June 1, 3 miles east of C'oulterville, contained 2 small embryos. By late autumn (November), young born during the current year weigh about .") ounces (150 grams), which is about three-fifths the weight of adults. Gray Bushy-tailed Wood Rat. Neotoma cinerea cinerea (Ord) Field characters. — Size larger than Stieator Wood Kat or House Rat; tail shorter than heatl and body, with long hairs on sides forming a flat brush (figs. 12c, 15) ; pelage thick and soft. Head and body 7 to 9% inches (180-237 mm.), tail 4% to 7% inches (120-188 mm.), hind foot 1% to 1% inches (40-46 mm.), ear from erown 1 to 1% inches (26-34 mm.); weight 9^2 to 16^4: ounces (271-459 grams). Coloration above sandy brown, tail somewhat darker; feet, and under surface of body and tail, pure white. Worl^ings: Sparse accumulations of sticks and other deliris in crevices among rocks. Droppings : Black, cylindrical, about M> by % inch. Occurrence. — Resident in boreal parts of Sierra Nevada. Recorded from near Gentrj-s (5900 feet) and Little Yosemite Valley eastward to Williams Butte. Life zone, upper Canadian and whole of Hudsonian. Lives in rock slides and in and about logs. Noc- turnal ; partially colonial. The Gray Bushy-tailed Wood Rat is an inhabitant of the higher and more easterly portions of the Yosemite section and so comes only to the attention of those visitors who spend some time in the back country. When human beings do become aware of the presence of this rodent it is because the animal literally forces itself upon their attention. Campers tell many tales, some humorous, some semi-tragic, of the activities of the big 'pack- rat' or 'trade rat' among their belongings. The range of this species is separated from that of the foothill-inhabiting Streator Wood Rat by a hiatus usually several miles in width and a gap of at least 1500 feet in altitude. The nearest approach of one to the other, according to our records, is that of streatori on the floor of the Yosemite Valley to cinerea on the slopes close above Gentrys. The main range of the bushy-tail involves the belt of country characterized by the alpine hemlock, namely the Hudsonian Zone. A few of these rats live at or above timber line, as on Mount Lyell (up to an altitude of 18,090 feet) ; and on the east slope of the Sierras, as at Walker Lake and on Williams Butte, they occur at much lower altitudes and in lower zones. In the Yosemite region the Bushy-tailed Wood Rat is an inliahitant of rock slides. A very few were captured away from rocks, but only enough to emphasize the mass preference of the species for heaps of talus. There are rock slides in the Transition and Canadian zones on the west slope which to our eyes seem indistinguishabh' from those at higher levels, but the bushy-tails do not inhabit them, Tniniediate conipclit ion with the other near-related species is lacking, for the Streator Wood Rat is not found to any large extent in the Transition Zon(> rocks and is entirely absent from the Canadian. WOOD BATS 121 When compared with the common round-tailed, house-building wood rat of the western foothills, the bushy-tail is found to be of the same general form, but it is larger and heavier, with longer fur. (See fig. 15.) The hair on its tail is elongated so that this member has something of the flat, brush-like appearance associated with tree squirrels and chipmunks. The dense body coat of the Bushy-tailed Wood Rat is doubtless an adaptation to life in a boreal region. The general configuration of the head and body of this species, especially if seen in a rock slide Avhere the tail may be concealed, reminds one of a cony. Fig. 15. Gray Bushy-tailed Wood Eat. Photographed from animal freshly trapped near A'ogelsang Lake, August 31, 1915. A feature of this wood rat is the musty odor which is associated with both the animal and its home precincts. This odor is produced by glands at the side of the anus, a condition similar to that obtaining in the skunk. Places which are continuously inhabited by the bushy-tail take on this odor, the presence of which furnishes a clue to naturalists who may be hunting for places to trap the animals. The present species like its foothill relative is essentially a night prowler. The rat traps, baited with rolled oats, which we set in rock slides at eleva- tions above 8000 feet trapped conies during the daytime and Bushy-tailed Wood Rats at night. On but one occasion did we see a Bushy-tailed Wood Rat abroad during the daytime. On July 18, 1915, four members of our field party had ascended to the summit of Mount Lyell, and while we were eating lunch there a bushy-tail came forth and gathered lunch scraps which we and previous A-isitors had dropped. Bits of hardtack scattered on the rocks were eagerly sought and devoured, though the rat retired into a crevice to chew them up. No general source of natural food was to be seen on the peak. 122 ANIMAL LIFE IX THE YOSEMITE This species is less of a builder than its foothill cousin. Nowhere did we find the large accumulations of material that the Streator Wood Rat gathers. In a few places bushy-tails had accumulated twigs, sticks, old bones, and similar material in crevices among the rocks, much after the manner of tiie Streator Wood Rat in the boulder taluses of Yosemite Valley. But many of the localities inhabited by the bushy-tail were entirely devoid of building material of any sort. Since there are, in such places, many crevices within the rocks in which the animals may take shelter, they have, perhaps, no need to build elaborately. In those cases w^here we saw no external evidences of a nest, there may have been inhabited shelters deep down among the rocks where human beings and the larger carnivores could never penetrate. The young of the Bushy-tailed Wood Rat are produced during the mid- summer season. One female, taken in Lyell Caiion on July 17, 1915, contained 3 embryos. The females have only four teats, which suggests that the litters are small. Several females captured between July 9 and 21, 1915, gave evidence of having recently suckled young. By the last week of August young were being trapped in considerable numbers and were then from one-fourth to one-half the weight of the parents. Their juvenal pelage is very soft and short and lacks the prominent sandy brown overcast seen on adult animals. At this age the tail is only beginning to show the lengthened hairing at the sides and end. Yosemite Meadow Mouse. Microtus montanus yosemite Grinnell Field characters. — Body size about three times that of House Mouse; tail short (fig. 16a), less than % head and body; pelage long and lax; ear nearly buried in fur. (See fig. 20b.) Head and body 4% to 5% inches (112-138 mm.), tail 1% to 2^^ inches (35-54 mm.), hind foot about % inch (20-22 mm.), ear from crown % to % inch (10-17 mm.); weight 1% to 2% ounces (38.0-74.8 grams). Coloration dark brown above, sometimes with a reddish tinge on back; under surface dark gray. Workings: Pathways or runways 1 to 1^/^ inches wide, cut along surface of turf and connecting \vith small round holes in earth, which are always open. Occurrence. — Common resident chiefly in Canadian and Hudsonian zones on both slopes of Sierra Nevada. Rroorded from Gentrys (on Big Oak Flat Road) and from Mono Mea/, to 1% ounces (38.3-49.2 grams). Mariposac: head and body 5 to 5% inches (128-145 mm.), tail 1% to 2% inches (48-64 mm.), hind foot nearly 1 inch (21-25 mm.), ear from crown about Ms inch (10-14 mm.), weight 2>/j to 2ya ounces (64.0-73.8 grams). MEADOW MICE 127 Occurrence. — Common resident in Lower and Upper Sonoran zones on west slope of Sierra Nevada, Eeeorded from Snelling (subspecies aestuarinus) eastward to El Portal and Cascades (subspecies mariposae) Ao Inhabits grassland. The California Meadow Mouse is an inhabitant of grassy fields and marsh lands near the rivers and streams of the western part of the Yosemite region. Its range here is restricted to those rather scattered portions of the region which are open and fairly level. The species is common in the flat areas along the eastern margin of the San Joaquin Valley, but in the foothill districts it is for the most part found only in the scattered stream- side tracts which man has found to be most suitable for his own purposes. In general appearance and habits the California Meadow Mouse is much like the Yosemite Meadow Mouse which lives in the territory from Yosemite Valley to the crest of the Sierras, It is, however, of somewhat larger size and makes slightly wider runways. As with other meadow mice, the breeding season of this species is long. At Pleasant Valley and near Coulterville, in late May and June of 1915, young were already about in some numbers; and near El Portal in late November and even as late as December 5 (1914), half -grown individuals were trapped. On November 29, an adult female captured at El Portal was found to contain 5 large embryos. This number is probably an average. The food of this mouse consists chiefly of grass, which is freshly cut in lengths of about 1 inch, presumably so that it can be more readily carried along the runways and burrows. This meadow mouse, like others of its tribe, is subject to decided fluctua- tions in population from year to year. If one examines for a number of successive years the ground where the animals occur, one will note decided changes in the extent of their operations. In 1915, the population in the meadows adjacent to Bean Creek east of Coulterville seemed to be at a low ebb, for only by vigorous efforts in trapping could we obtain even a few individuals ; whereas, as a rule, the capture of meadow mice in numbers is a relatively easy matter. Many of the burrows and runways which we examined in this place were in a state indicating disuse. The holes were frequently covered with cobwebs, and small plant growths had sprung up in the runways. Neither of these conditions is to be noted in runs which are in current use by the mice. In 1920, trapping a short distance to the east of this locality, on Smith Creek, produced a number of the animals. At El Portal, on December 4, 1914, an adult meadow mouse was found with its hair firmly entangled on a twig in a brush pile. It had evidently made frantic efforts to escape, going round and round the twig, but this had only served to bind its hair all the tighter and being thus held the mouse perished, either from exposure or starvation. 128 AMMJL IJI'K IS THE TOSEMITE Meadow mice, particularly those species whicli inhabit runways, are given to extensive travel during the daytime. The runways are, in many instances, nearly or completely covered by the adjacent grass, and would seem to afford a more complete protection than is available to many of the other small rodents. Nevertheless, meadow mice, more often than other small rodents, fall victims to hawks; and their activity at dusk likewise results in manv of them being caught bv owls. ^fev: Fig. 17. Plan of the underground burrow system of a Mariposa Meadow Mouse. Excavated on meadows 3V^ miles east of Coulterville, June 8, 191."). Surface scale about 1:25. On a meadow at the head of Bean Creek east of Coulterville a series of runways and burrows of the Mariposa Meadow Mouse was opened up, studied, and mapped by two of our party on June 8, 1915. (See figs. 17, 18.) The meadow was covered with a dense growth of rush, foxtail grass, blue-eyed grass, soaproot, buttercup, wild celery, and other plants. The fine black humus through which the tunnels were dug was damp and the .soil a few inches below the surface of the ground was saturated with water. Some slight depressions in adjacent parts of the meadow still held standing water. The part of the meadow where the tunnels were located was very green; while on nearby higher and rockier parts the grass was already dry and no evidences of meadow mice were to be found. liOth surface runways and iiiKlcrgrouiid liinnels witc t'ouiid in this colony, but only the tunnel system is shown on the accompanying dijigram. Some of the runways led into holes which looked like abandoned goj^her holes, a fact which suggested that the meadow mice had i)ossibly made use of tunnels dug earlier by gophers. MEADOW MICE 129 SECTION AT "A-B" sump An area approximately nine feet square was gone over in detail and the sod lifted off so as to expose the tunnel system. The ground was so soft that for the most part the work could be done with the hands, only a few of the deeper parts requiring the use of a shovel. Some of the tunnels contained evidence of recent occupation by meadow mice in the form of scattered short cuttings of grasses and composites; in a few places there were footprints of the mice in the soft earth on the tunnel floor. A reddish material covered the floor in some of the old galleries, and here the foot- prints showed to good advantage. Scattered along the tunnels were the droppings of the mice. Only about half the tunnels which were opened up gave any evidence that they were in use during the current season. One recently built nest of dry grass, and part of an old one, were found in side pockets off two main tunnels. The newer nest cavity had two entrances, serviceable also as avenues of escape in time of danger, and there was also a short accessory loop leading around the nest. In various places there were 'sump' holes (fig. 18) which were dug to a lower level than the tunnels off from which they branched. These undoubtedly served to keep the tunnels drained, as each sump had more or less mud in its bottom. At other places there were slight side pockets or 'turn abouts' just large enough to hold a mouse. Only one hole connecting the surface runwaj^s and tunnel systems was found in the area studied. This is an unusual condition as compared with other 3Iicrotus runways which we have examined. Only one Microtus, quite a young individual, was obtained at this system of runways, though trapping was continued there for several nights. Sierra Cantankerous Meadow Mouse Microtus mordax sierrae Kellogg Field characters. — Body size more than twice that of House Mouse; tail slightly more than % head and body; pelage soft and dense. (See figs. 166, 20a.) Head and body 41/4 to 5 inches (108-128 mm.), tail 2 to 2% inches (50-66 mm.), hind foot about % inch (20-23 mm.), ear from crown % to % inch (13-17 mm.); weight about 1 to 1% ounces (30.3-48.0 grams). Coloration above dark brown with a grayish cast; sides of body conspicuously grayish; under surface grayish white; tail distinctly darker above than below. Occurrence. — Common resident, chiefly in Canadian and Hudsonian zones, on both slopes of Sierra Nevada. Eecorded commonly from Merced Grove Big Trees and Chin- Pig. 18. Enlarged section through part of burrow system shown in figure 17 in region indicated at "A-B." 130 ANIMAL LIFE IN THE YOSEMITE quapin eastward to Warren Fork of Leevining Creek and Walker Lake; present on floor of Yosemite Valley in some numbers and taken once at El Portal. Lives chiefly along banks of swift-flowing mountain streams and in marshes but also on dry hillsides at some distance from water. Largely nocturnal. Besides the path-cutting meadow mice (californicus and montanus) there is present in the Yosemite region a free-ranging species, the Can- tankerous Meadow Mouse. It occurs in greatest numbers on the ground beneath the bushes which line the banks of mountain streams, but strangely enough is also found in some numbers on dry hillsides well away from water. iC.O M.m. siei-rae /\ ^■ m.sierrae m^psenilte c M.m.yosemite : y \JTvf _ ■^^. ^ »^s^ 9000 1 "^^ LIFE ZONeS 7000 j 1 _,_— ^"'^0^^^^''''^ 1 1 ABCTIC ALPItJE ; ^..^rt^^^!!^^'^^^^^^^^^^^'''^^ @ muOSOnian '°'"' M.c.man>osae ; y^^^ i 1 CANADIAN OH TRANSITION ^^^^ 1 ^^ M. c.aestua^inus^„-?ared with most other rodents, probably enjoy an 'expectation' of long life. MOUNTAIN BEAVEE 155 Sierra Mountain Beaver. Aplodontia rufa calif ornica (Peters) Field characters. — Size of small Marmot, T\"ith general appearance of Meadow Mouse; tail so short as to appear to be wanting, shorter than hind foot; head blunt, eyes and ears small (pi. 31a). Head and body 11 to 14 inches (280-354 mm.), tail % to 1% inches (19-40 mm.), hind foot 2% to 2% inches (55-63 mm.), ear from crown % to % inch (13-21 mm.); weight 30 to 48 ounces (852-1375 grams). General coloration every- where plain blackish brown. Workings: Underground burrows or tunnels about 6 to 7 inches in diameter with numerous openings to surface; located usually along brush- covered banks of swift -flowing streams. Occurrence. — Resident locally in small numbers in Canadian and Hudsonian zones on west slope of Sierra Nevada. Eecorded at Aspen Valley, Gentrys, Chinquapin, near Ostrander Eocks, in both forks of Indian Canon (above Yosemite Valley), near Porcupine Flat, and in head of Lyell Canon. Altitudinal range, 5800 to 10,000 feet. Lives along swift -flowing streams bordered by willow and creek dogwood. Colonial; nocturnal. One of the most interesting and at the same time reclusive members of the Yosemite fauna is the Mountain Beaver or Aplodontia. This animal, like the redwood tree and the wren-tit, is peculiar to the west coast of North America, where it occurs scatteringly in the Sierras and northern coast ranges. Although called Mountain Beaver it is in nowise related by structure or mode of life to the true beaver save that both are rodents. The present species has, indeed, no close living relatives anywhere so far as known. Locally we found that some of the workmen on road gangs who knew of the animals called them 'mush-rats' because of their general resemblance to the muskrat. The latter animal does not, to the be.st of our knowledge, occur anywhere in the Yosemite region. The Sierra Mountain Beaver is of the size of a small marmot. If one can imagine a meadow mouse grown to fifteen or twenty times its ordinary size, and practically without any tail, one will have a good idea of the mountain beaver. (See pi. 31a..) The animal is of stout build, has a short blunt head, small eyes, small nearly naked ears, no obvious neck, a thick body, normal legs and feet, and a mere stub of a tail. The tail is less than the hind foot in length, and in this character the animal is unlike all local small mammals except the rabbits and the cony. The body is covered evenly with a uniform blackish brown pelage of considerable length and of soft texture. Aplodontia is a timid, retiring animal, practically never seen except when trapped. Its activity is confined to the night-time, and it spends the day in underground retreats. When in captivity the least injury seems sufficient to cause its death; its general resistance seems extremely low. When kept as a captive it may be tamed rapidly, and even at the first its only indication of displeasure is a rapid chattering or grinding with its teeth. 156 ANIMAL LIFE IN THE YO SEMITE Only once, in our rather extended and intensive work in the habitat of Aplodontia, did any of our party happen to see one of the animals abroad. On the evening of June 23, 1915, at 7 :05 p.m., one was seen run- ning along the bank of the creek in Indian Caiion (northeast of Yosemite Falls). It moved very rapidly, at perhaps 5 feet a second, and its gait w^as like the lumbering gallop of a bear. At our Lyell Canon camp a month later a specimen of Aplodontia was trapped alive and kept for a while in camp (pi. 31a). The manner of life of the mountain beaver is, like its general appear- ance, suggestive of that of the meadow mouse. It frequents, almost without exception, the near vicinity of streams. When the naturalist goes in search of Aplodontia he seeks creek banks bordered by good growths of willow, creek dogwood, and other riparian shrubs and herbs. On the stems of these, marks of gnawings will be in evidence if the animals are present. Also burrows or tunnels in the ground will be found often within but a yard or so of water. These tunnels, like those of meadow mice, are, in general, parallel with the surface of the ground, and have rather frequent openings to the surface. (See fig. 31Z>.) Within these burrows the animals make their nests, in which they remain during the daytime and within which their young are reared. At Chinquapin a series of Aplodontia workings was laid open and mapped by one of our party on June 21, 1915. The tunnels ran partly through rocky ground and partly through humous soil. Close by was the north fork of Indian Creek in which the stream of water was about 2 feet wide and 3 to 6 inches deep. Water was also running through one of the tunnels. The tunnel system, for the most part, was in the bank, about 3 feet above the level of the stream. The tunnels averaged between 6 and 7 inches (160 mm.) in diameter, the entrances being slightly larger. No nest was found in the series of tunnels opened, but examination of tunnel systems elsewhere has shown the presence of underground nests, so it may be presumed that the animals which made this particular excavation had their nest in some other burrow. The floor of the tunnel system is usually well packed as a result of constant use and is kept clear of debris of every sort so long as the place is occupied by the animals. The set of tunnels at Chinquapin yielded 2 animals, a male and a female, in the several days of trapping prior to the time wlion Ihc system Mas dnjj: oul. Another colony was noted along the East Fork of Indian Canon (above Yosemite Valley). Here the workings occupied, in 1915, practically all available locations from the crossing of the trail to North Dome northward to the headwaters of the creek. In one place, even during Jnne, the creek practically disappeared from view so great was the ajnount of water running through the tnnnels. Other colonies wore found on creeks near MOUNTAIN BE AVER 157 Porcupine Flat; and finally a colony of Aplodontia was discovered at an altitude of 10,000 feet on the slope of Kuna Crest in the head of Lyell Cafion, (See fig. 21.) The lowest record, altitudinally, was made at Gentrys, 5800 feet, Avhere, in the fall of 1915, tunnels were found in fair numbers though none of the animals was obtained. The 'colonies,' or at least the series of workings so called, are in many cases of considerable extent. In one place an area estimated at 50 by 100 yards was occupied; other colonies were of somewhat less extent. The number of holes in a colony is large, 20 to 30 being noted in one locality on Snow Creek. The population in any one limited series of burrows consists usually of not more than two adults, comprising a pair. If these are trapped out, several days intervene before animals from neighboring burrows move in, to occupy the deserted ones. The colonies are in most cases fairly well sheltered from view by the vegetational cover of the stream banks. But in early spring, just after the snow has melted off and before the willows and dog^vood are leaved out, the burrow openings may be readily seen. Aplodontia seems to be active, even at the higher levels, throughout the year. There are no data to indicate that the animals hibernate, while much circumstantial evidence points toward regular active life throughout the winter season. In many places we saw willow branches and small conifer- ous trees which showed signs of beaver activity as high as 5 feet above the ground. This animal is not known to climb to any extent, so the conclusion seems justified that it comes up through the snow, even out on the surfa.ce of the snow, and nibbles at the twigs then within easy reach. Along the west fork of Indian Canon (above Yosemite Falls) a quantity of 'hay' was observed, consisting of a narrow-leaved lupine (Lupinus longipes) which had been cut green and piled and cured on dry masses of drift material. This 'hay' when seen on October 30, 1915, was nearly dry. In each pile the butt ends of the stems usually lay in one direction, toward the entrance of the adjacent burrow. Whether this material was for winter food, as with the cony, or for a dry and warm winter nest below-ground, was not ascertainable. Aplodontia feeds upon most of the plants growing in the vicinity of its burrows. At Chinquapin the following plants gave evidence of being used by the animals: Azalea (Rhododendron occidentale), the commonest plant and used very much ; hazel, common but little used ; Sierran currant (Ribes nevadense), common, and many cuttings seen; creek dogwood (Cornus pubescens), common, many cuttings; wild cherry, fairly common, a few cut twigs seen; snow-bush (CeanotJius cordidatus) , abundant at edges of thickets and occasionally used; chinquapin, abundant at edges of inhabited thickets and much used in places; incense cedar, few young 158 AXIMAL LIFE IN THE YOSEMITE trees much used ; white fir, many young trees, but rarely used ; sugar pine, young trees common but only occasionally used; brake fern (Pteris nqvi- Jma), fairly common, used slightly. From the azalea, snow-bush, hazel, and cherry, sticks 14 inch in diameter and 6 to 8 inches long were cut; the pines and cedars had the smaller twigs pruned off. One azalea stem IY2 inches in diameter had been cut through but had not been carried away. Chinquapin stems which were taken had the leaves still in place. Elsewhere in the region still other plants showed signs of having been used as food. In one place young aspens had been eaten ; and Labrador tea {Ledum gJandidosum) and another currant {Ribes viscosissimum) had been cut by the animals. In one instance a 'whole bush' of creek dogwood had been cut off at about 18 inches above the ground. Although living in a damp environment, in some places where it must of necessity enter the water at times, there is no evidence that Aplodontia does so by preference. It is not nearly so aquatic in habits as the musk- rat or the true beaver. When the fur of Aplodontia is touched by water it wets about as readily as that of other less aquatic animals. The breeding season of Aplodontia seems to occupy the summer months. Females containing embryos are very seldom taken, "We did not secure a single one in the Yosemite region. A quarter-grown youngster weighing about 6 ounces (182 grams) was trapped in Lycll Canon, July 20, lOlf). Other animals frequent Aplodontia burrows to some extent. Several Sierra Chickarees were caught in traps set in Aplodontia burrows and well out of view from above. One Mountain Weasel Avas taken in a similar setting. The contrast in vitality between these animals and Aplodontia is marked. Aplodontia even when held lightly by the trap was usually dead when found. The squirrels and weasels had survived, doubtless for several hours. Southern Sierra Marmot. Marmota flaviventer sierrae llowi'll Field characters. — Body size about that of small badjjor; body stout; legs and tail short. Head and body 14 Va to 18 14 inches (370-464 mm.), tail 5% to 8 inches (130- 200 mm.), hind foot 2% to 3% inches (70-84 mm.), ear from crown % to 1 inch (l.'>-24 mm.); weight 4% to 7 pounds (1.94 to 3.2 kilograms). General coloration yellowish brown grizzled or 'ticked' above with white; chest an' distinctly. In the spring, when the new growth is just appearing, the trails are still conspicuous, as the vegetation is slower in starting there than in the adjacent unbeaten tracts. Soon, how^ever, the trails are entirely obliterated, save as the animals renew them by further use. It seems likely that ground squirrels can, if necessity demands, go without water for long periods of time, if not indefinitely. Many of the plains-dwelling individuals of this species are so situated that it is im- possible for them to get any water except such as may accumulate in small surface depressions or in parts of their burrows for brief periods during the rainy season. As a substitute for bathing in water these animals take dust baths in the soft earth of fields and country roads. We have frequently come upon places where tracks and marks in the dust showed that squirrels had been 'dusting' themselves. This habit may afford partial relief from the many fleas and mites with which they are often afiflicted. Ground squirrels, like chipmunks, are provided with inner cheek pouches which are used while gathering and IrarLsporting food. Often when the animals are scared out of bushes or trees, or away from some supply of roots or bulbs which they have discovered, their cheeks are seen to be bulging with the contents of these pouches. They are able to use their teeth even when these pouches are widely distended. Ground squirrels are chiefly terrestrial in their forage habits, taking whatever may offer in the way of seeds, grasses, fruits, low-growing annual plants, roots, and especially bulbs like those of the common brodiaea. The GBOUND SQUIBEELS 167 animals do leave the ground, however, and ascend shrubs and low trees for especially desirable provender. In Yosemite Valley, Mrs. Joseph Grinnell reports that ground squirrels were gathering the green fruits from the top of a 4-foot manzanita bush. At Pleasant Valley we occasion- ally saw them in low oaks, evidently after acorns; and at El Portal one squirrel was found with three of the large acorns of the Golden Oak, two in one cheek pouch and one in the other. At Snelling, in January, they were eating the coarse fruits of the osage orange, which abounds there as a hedgerow plant ; torn remnants of these fruits were scattered about the entrances of the burrows. But the ground squirrel is not entirely restricted to a vegetable diet, as is shown by the fact that it is regularly captured in meat-baited traps set for skunks and other carnivorous animals. Mr. E. W. Baker, formerly resident in Yosemite Valley, has told us that the ground squirrels about Yosemite Village would, in the fall, come and fill their cheek pouches with acorns and then go off and store them in some safe place for the winter or spring when food would be scarce. He says that the present species, like the gray squirrel, is not averse to stealing young birds. He has seen a California Ground Squirrel carry off a young "Western Robin, and he has received report of their capturing young chickens in yards on the floor of the Valley, Numerous visitors to the Valley during the summer months establish feeding tables to attract the birds about their camps, and many of these persons find that ground squirrels give more or less trouble. At first exceedingly shy, the squirrels soon become bold and eventually have to be driven away in order that the birds may have the benefit of the proffered food. In the lowlands the majority of the young ground squirrels are born in April and May, and by the middle of May some are beginning to appear with their mothers, playing about the mouths of the burrows; but in the higher altitudes the young are born later. Two half-grown young were seen on May 17, 1919, in Yosemite Valley, but in other years some of the females in the Transition Zone and lower part of the Canadian Zone had not yet given birth to their young by the first week in June. 'Spring' in the lowlands comes in April and early May, while the 'spring' of the higher altitudes does not occur until late June or July. Hence the young do appear at the same season, considering the differences in temperature conditions at the different elevations. The annual molt takes place in mid-summer. With the advent of the new pelage, the white areas on the sides of the head and neck become more conspicuous and the pepper-and-salt effect resulting from the banded coloration of the individual hairs is more in evidence. As time goes on the freshness of the coat is lost by wear against the sides of the burrow and in other ways. The brown overwash which the new pelage possesses 168 ANIMAL LIFE IN THE YOSEMITE loses its reddish cast, and the hair becomes yellowish or grayish brown in appearance. There is thus some variation in the tones of coloration shown by squirrels of this species at different times of the year, irrespective of molt. Belding Ground Squirrel. Citellus beldingi (Merriam) Field characters. — Body size about that of Ilouee Eat; tail sparsely haired at sides, and short, decidedly less than half length of head and body; ears small and round, not pointed or tufted. (See pi. 2.) Head and body 7 to S'/o inches (180-215 mm.), tail 2% to 3 inches (60-74 mm.), hind foot about 1% inches (41-45 mm.), oar from crown % to V2 inch (8-13 mm.); weight 71^ to lO^i ounces (207-294 grams). General color- ation light yellowish brown, paler on under surface of body; a broad area of bright reddish brown down middle of back. Voice: General warning call of 5 to 8 shrill short whistles, seek, in quick succession; females with young utter a single note, e-chert', at intervals. Workings: Burrows in ground, surface openings about 2 inches in diameter. Occurrence. — Common resident in higher and more easterly portions of Yosemite region, chiefly but not entirely in Hudsonian Zone. Eecorded from near Porcupine Flat and from near Merced Lake eastward to Mono Lake Post Office and to Farrington ranch near Williams Butte. Eanges upward to 11,500 feet as on Parsons Peak, and higher yet on Conness Mountain. Inhabits chiefly grassland, occasionally rocky places, or floor of open forest. Diurnal. The Belding Ground Squirrel is a hardy, ground-dwelling member of the squirrel family inhabiting the meadows and other grass-producing areas in the higher and more ea.sterly portions of the Yosemite section. This species is often called * picket-pin' because of the erect, stake-like posture which it assumes when on the lookout for danger (pi. 2). Some persons have referred to it as "spermophile" (seed eater). Both of these names have a measure of appropriateness not alw^ays to be found in vernacular names. This squirrel is named for Lyman Belding, the naturalist formerly resident in Stockton who collected the specimen from which the species was first scientifically described. The range of the Belding Ground Squirrel begins on the west slope of the Sierras at about the lower margin of the Hudsonian Zone. The western- most report of its occurrence is from the upper Yosemite Creek in a loca- tion west of Porcupine Flat and due north of the Yosemite village. The first specimens actually obtained by our party were collected about two miles east of Porcupine Flat. Merced Lake is the westernmost point of record for the southern part of the section, in the drainage of the upper Merced River. The maximum abundance of the species is to be found on the larger high mountain meadows, such as Tuolumne Meadows, in the heart of the Hudsonian Zone. (See pi. 18?).) While one of us was travers- ing the meadows in Tioga Pass on July 13, 1915, hilly 100 of these scpiirrels were observed; and an equal number was counted about two weeks l;itt>r while we were going along the floor of TjvcII CaMon. The range of the GROUND SQUIERELS 169 species extends upward on the Sierran crest to well above timber line, for example, on Conness Mountain, Parsons Peak, and Parker Pass. On the east slope this squirrel is found down through the Canadian Zone (Jeffrey pines) even to the Farrin^on ranch near Williams Butte and to near Mono Lake Post Office, close to the shore of Mono Lake. Meadows constitute the preferred habitat of this species, and by far the greater percentage of the animals are to be found in the grassland. But this environment is not absolutely essential to their welfare; for some of them live in rather rocky places and some in areas which bear a moderate stand of trees. In the latter two situations there is usually bunch grass in the neighborhood of the places inhabited by the squirrels. The limited patches of grass about many of the small glacial lakes often support small populations of the Belding Ground Squirrel. This species is as strictly terrestrial as any ground squirrel of which we know. We have never seen one climb a tree or even a bush. Once one was seen on the top of a boulder about 3 feet in height. The Belding Squirrel is less given to clambering over rocks than the 'copperhead' or any of the chipmunks. Yet the present species, despite its habit of remain- ing on the ground surface, spies out its enemies, real or supposed, at fairly long distances and communicates at once with others of its kind in a way that puts all the individuals in the neighborhood on their guard. When the traveler approaches a meadow and is still a hundred yards or more from the nearest Belding Squirrel, his ear is assailed by the alarm call of the animal, a series of shrill piping whistles, loud enough to be heard by any living creature within a quarter-mile radius. Usually there are 5 to 8 (rarely even 12) notes in rapid sequence. Other squirrels take up and repeat this calling so that on some occasions the rocky walls enclos- ing a meadow resound with their notes. This warning call is responded to according to the circumstances wherein the various individuals find them- selves when the call is heard. Those out in the meadows usually at once run toward their burrows ; others closer by, within a few yards of their homes, rise straight up on their haunches, with forelimbs pressed against the body. When an individual squirrel has assumed this position, it, too, utters the shrill whistled call. If its curiosity remains unsatisfied, as when its view of the approaching person is imperfect, the squirrel rises still farther until it is standing bolt upright on the soles of its hind feet. The call given then is apt to be of an even more penetrating quality than at first. If the person continues to approach, the squirrel drops to all fours and runs to the entrance of its burrow where sometimes it again assumes the 'picket-pin' position; but it more often remains hunched up on all fours, with its hind feet well under its body, ready to dart down the hole at an instant's further warning. Even when in the upright position at 170 AS'IMAL LIFE IS THE YOSEMITE the mouth of the burrow the rapidity with which a sfiuirrd can drop into its retreat is surprising. Once scared into the ground it stays only a short time, then pokes its head out again, to just below the level of its eyes. When sitting erect and observing its surroundings a squirrel can often be seen to twitch its nose as if sniffing and drawing in the air. Probably it uses the sense of smell to aid its powers of sight and hearing. On fiat open land where gra.ss is at best very short, the usual mode of progression for this .squirrel is a heavy run, with little up and down move- ment of the body, and with the tail down. In high gra.ss, instead of parting the stalks and running between them, the squirrel progresses by a series of jumps; each hop carries the animal up so that it can look about for some distance and be able to spj' an approaching enemy. Once a Belding Squirrel was come upon in a rocky place; the animal ran over some rocks and jumped over a creek which was fully 2 feet wide, in its effort to escape. Another, on Mount Hoffmann, ran along the face of a pinnacle of rock, clinging to small cracks in the surface. The Belding Ground Squirrel subsists chiefly upon gra.ss and gra.ss seeds, and depends less upon the larger seeds, nuts, and roots such as are eaten by the California Ground Squirrel and the chipmunks. When feed- ing, the animal sits in a hunched-up position, the hind legs in entire support of the body. The forefeet, when grass is being eaten, are used to draw the grass stalks or heads toward the mouth where they can be cut off. Larger items are held in the forepaws, while small pieces are nibbled off Avith the front (incisor) teeth and rapidly ground up by the cheek teeth (molars). In a few instances Belding Squirrels were captured in meat-baited traps set for carnivores. Certain other members of the squirrel family seek flesh bait when available, but the present species seems to be more restricted in its food preferences to vegetable material. At the mule corral on Tuolumne Meadows in 1915 the 'picket-pins' were foraging around barley sacks, gleaning scattered grain like rats. Several Belding Squirrels were caught in steel traps set in the entrances to Marmot burrows, and one wtis captured in a Macabee gopher trap which had been set in a gopher burrow. Each 'picket-pin' evidently restricts itself closely to use of its own par- ticular burrow and does not, in time of danger, dart into what<'vor retreat happens to be nearest at hand. On liyell Meadows one was repeatedly .seen to run from the meadowland, where there were luimerous holes, to a i>ar- ticular burrow in the granite gravel above the trail. Near the same place, one of our party suddenly came upon one of tbcsc squirrels, posted at 'observation,' within one foot of an open burrow. The s(piirrel, instead of darting into this nearest hole, ran to one fully 30 feet farther away. The burrows are usually constructed right in the meadows which furnish the animals llicir food; less fr('(|U('iitly they aiT dug in tin* rocky soil at GROUND SQUIBB ELS 171 the margins of the meadows. Those squirrels which live in the bunch-grass areas at or above timber line make their burrows, of necessity, in the granite soil, A typical meadowland burrow at Snow Flat was opened and studied by the authors on June 28, 1915. This burrow was close to the bank of a small creek, which meandered through the meadow, and 'was near a large granite boulder. The ground was heavily matted with grass roots to a depth of 1% inches (45 mm.) and all the tunnels had been excavated below this mat. The whole tunnel system was remarkably level, unlike those of the California Ground Squirrel in the lowlands; but this may have been conditioned by the nearness of the creek and of the water table. Two short, deeper tunnels which were found may have been prospects toward a deeper system which would have been excavated later in the season. There was melting snow about the meadow and the ground was quite Avet on the date of our study, especially below the level of the tunnels laid open. The presence of this extreme amount of moisture may have acted to deter the squirrel from going any deeper. The total length of all the tunnels in this system was 53.3 feet (16,25 meters) and the average tunnel diameter 2 inches (52 mm,). The total amount of earth excavated was therefore 2010 cubic inches — 8.7 gallons of earth, or nearly enough to fill two 5-gallon oil cans. Yet there were no mounds of earth at the entrances to the burrow. The soil had either been pushed into the creek or else washed away by the summer rains and melting snow water. This burrow system contained no well constructed nest; but in one place there was some grassy material, either the remains of an old nest or, more likely, the beginning of a new one. The inhabitant of this burrow was a female which would have given birth to young, within two weeks probably. One burrow of this species was noted at the base of a lodgepole pine. In this case there was a mound of earth at the entrance. The young of the Belding Ground Squirrel are born about the first of July, there being, so far as all ovir evidence shows, but one brood per year. Yet a pair was seen in what looked like a mating pursuit as late as July 13. The number of young was ascertained definitely in only one case, that of the female containing 5 embryos, at Snow Flat, June 28. A female obtained July 2 east of Porcupine Flat had evidently just given birth to 6 young. In females taken on July 8 and 21, 1915, the mammary glands were functional. The young, when they first appear above ground, are scarcely more than one-third grown. The first young were noted in 1915 on July 25. But near Williams Butte three young only a third grown were seen on June 28 (1916). At the end of July (27-31) in 1915, in Lyell Caiion and on Tuolumne Meadows, young were out at the mouths of 172 ANIMAL LIFE IN THE YOSEMITE burrows in numbers, usually in groups of five and six. At Tenaya Lake on July 29 the young animals seen were larger than those at the higher stations. It is therefore probable that the young are born earlier at the lower altitudes than at the higher levels. The record at Williams Butte goes to substantiate this belief. Full size is not attained for some weeks ; young weighing scarcely more than half as much as adults were taken at Merced Lake August 31 and in Tioga Pass September 25, 1915. As early as July 26 small new burrows with mounds of earth at the entrances were beginning to appear on Tuolumne Meadows. These were evidently made by young which had been turned out of the parental burrows to shift for themselves. When the young first go above ground they frisk about the entrance to the burrow under the watchful eye of the female parent. In Lyell Caiion on July 25, 1915, one of us came upon a single young animal running in and about some rock crevices adjacent to the burrow at the side of the meadow. The mother was standing guard, uttering her note, e-chert', every few seconds. The observer 'squeaked,' whereupon the parent squirrel at once rose upon her hind feet in the picket-pin position and uttered the shrill piping warning call of the species ; the youngster promptly ran into the burrow. The adult remained standing on her hind feet for 48 seconds, then sank down on her haunches. A day or two later, another family group consisting of a female and 2 half -grown young, on Tuolumne Meadows, was studied at close range for some time." At first the youngsters did not venture very far out of the hole; and when they did they remained on the far side of their mother. Later, they gained courage and came more into view, one being more ven- turesome than the other. The mother stood much of the time in the picket- pin position giving the e-chert' call. At each utterance her body was shrugged up, the head and shoulders thrown forward and the tail given an upward flip ; much effort seemed to be put into the production of this note. In cases where families of 5 or 6 young were seen, they all sat close about the entrance of the burrow and when frightened all attempted to crowd into the hole at the same instant. One youngster, bewildered by some horses, ran directly at one of our party and then escaped into a shallow hole some distance from its home burrow. The Belding Ground Scjuirrel escapes the rigors of the Sicrran Avinter — when the temperature falls low and all the grasslands are blanketed in 14 This was done by the method of direct approach. The observer parbod in dull brown-colored outinfj clothes, started about 100 fcot away and advanced slowly in a direct lino toward the sqnirrcls. As he came closer his movements were made slower and glower so as not to startle the animals. Sidcwise movement was avoided in every possible way. The squirrel, usinfj monocular vision, wius thus less able to appreciate his approach. This method is very useful in getting close to birds or mammals in order to study or photograph them. GROUND SQVIEEELS 373 snow — by hibernating. The exact duration of the hibernation period is not known. At the Farrington ranch, near Williams Butte, one of these squirrels was obtained on April 29, 1916. In many localities individuals are out before all the snow has disappeared, and in places they have been seen to run over snow banks. At the end of September many of the animals were still abroad in Tioga Pass and on Tuolumne Meadows, even after a slight snowfall. Our latest record is of an individual out at Ten Lakes on October 6, 1915. The only direct evidence of enemies is a note that at Tuolumne Meadows a Mountain Weasel was seen killing one of these squirrels. The weasel had the squirrel bj'' the back of the neck. The larger high-mountain carnivores probably also levy toll on the Belding Ground Squirrel whenever oppor- tunity offers. Stephens Soft-haired Ground Squirrel Citellus mollis Stephens! (Merriam) Field characters. — Size near that of House Eat; ears small; tail short; pelage silky textured. Head and body 6% inches (162 mm.), tail 2 inches (50 mm.), hind foot l^^i inches (32 mm.), ear % inch (4 mm.) [measurements from extralimital specimens]. General coloration buffy gray above, silvery white on under surface; feet dull -white; tail drab on upper surface, buffy below. Workings : Burrows in ground beneath bushes. Occtirrence. — Eesident at extreme southeastern corner of Yosemite section, near Mono Mills. Lives on sandy ground beneath sagebrush. The Stephens Soft-haired Ground Squirrel is a Great Basin type of rodent which reaches the extreme eastern margin of our Yosemite section in the dry sagebrush-covered, sandy area southeast of Mono Lake. Its presence there is established by two specimens which were captured on June 10 and 11, 1916. These two individuals are not quite full grown. Others were present in the same place, but not obtained. The field notes state that the squirrels slid along on the ground like big lizards and like them stopped and scrutinized the observer from the shelter of the first bush that they reached. Sierra Nevada Golden-mantled Ground Squirrel Callospermophilus chrysodeirns chrysodeirus (Merriam) Field characters. — Size of body about two-thirds that of House Eat; tail about half length of head and body. Head and body 5% to 7% inches (147-195 mm.), tail 2% to 4 inches (67-102 mm.), hind foot IY2 to 1% inches (38-43 mm.), ear from crown % to ^ inch (11-20 mm.); weight 4% to 8i^ ounces (135-239 grams). Whole head and neck yellowish or coppery red (pi. 2) ; on each side of back a broad white stripe bordered above and below by broad black stripes; middle of back grizzled brown; sides and under surface of body pale gray or whitish; tail black centrally, buffy at margin, cinnamon on under surface. JVorlings: Holes in ground 2 to 2^2 inches in diameter, usually close to rocks or logs. 174 AXIMAL LIFE IN THE TOSEMITE Occurrence. — Common resident in Canadian and Hudsonian zones on both slopes of Sierra Nevada. Recorded from Aspen Valley, Merced Big Trees, and near Chinquapin, eastward to Warren Fork of Lcevining Creek and to Walker Lake. Lives on ground in open forest and also in rocky situations. Diurnal. The Golden-mantled Ground Squirrel is one of the most conspicuous members of the high mountain fauna, for it is the most brilliantly marked of all the local squirrel tribe. People living in the mountains usually term this species the "copperhead" or yellow-headed chipmunk, both of which names are appropriate as applying to the coloring on the head and shoulders (pi. 2). In general ecology this squirrel is the high-mountain counterpart of the well-known California Ground Squirrel of the lowland vallej'S and foothills. In size the copperhead is our smallest ground squirrel. It is about three-fourths the size of the Belding Ground Squirrel and only one-third or one-fourth the size of the California Ground Squirrel. It is larger, however, than any of the chipmunks. Its general appearance, with stout body and short tail, readily classifies it as a terrestrial squirrel rather than as a climber. The range of the copperhead practically coincides with that of the lodgepole pine; yet the squirrel is in no way dependent upon this tree directly. The lowest station of record for the * ' callo, ' ' as members of our party got in the habit of calling the animal for short, is at Merced Grove Big Trees, altitude 5500 feet, a place which also marks the western limit of its range. Across the Sierras the whole of the Canadian and Hudsonian zones is inhabited, eastward to Walker Lake; sparingly to INIono Craters. On the high peaks this species does not seem to go much above timber line. Thus, on Mount Florence, the last individual was seen at 10,700 feet, which was just above the highest stunted white-bark pines. On one occasion, at Gaspipe Spring, east of Mono Mills, one of these .squirrels was come upon on the ground in the sagebrush, "miles from any timber." The main habitat or niche of this squirrel is the open rock-strewn floor of the sparse lodgepole pine forest. It keeps closely to this sort of environ- ment, while the Belding Squirrel inhabits the open meadows. At the margins of the meadows, however, the two are often seen in association. The "callo" is strictly a ground dwelling animal. When it wants to look about, it may go to the top of a low boulder or of a log. Only once did we catch sight of one in a tree, and that individual when frightened ran down to the ground and quickly sought its burrow. The "callo" when first met with is rather shy and usually scampers to the vicinity of its burrow, where it sits hunched uji, like a California Ground Squirrel, ready to dart into its underground retreat at an instant's further warning. But its confidence can be Avon ; about camps it may be GBOUND SQUIEBELS 175 studied at close range. The gait when running is heavy, with little or none of the bounding or skipping movements of chipmunks. On rare occasions a ' ' callo ' ' will assume the upright picket-pin posture so character- istic of the Belding Ground Squirrel. The "callo," quite in contrast with the other local squirrels, is seldom heard to utter notes of any sort. On one occasion, near Lake Tenaya, one of these animals was heard to give a high-pitched squeak, repeated three times. In mating chases, when a male pursues a female, low grunting and squeaking notes are uttered ; but these are inaudible beyond a few feet. The Golden-mantled Ground Squirrel spends the winter months, when snow covers the high mountains, in hibernation. Exact data on time of emergence and disappearance are lacking. When we reached Peregoy Meadow on May 20, 1919, the animals were already abroad. At Aspen Valley they were out as late as October 18 (1915), Probably they stay out until the first big storm of the season, which snows them in for the winter. The summer season is occupied by these squirrels in rearing their broods and in obtaining forage for themselves, not only for their daily needs, but also enough to permit of their acquiring the fat necessary for warmth and sustenance during the long winter sleep. Of one animal collected at Ten Lakes on October 9, 1915, the collector notes that "at least a handful of fat" was removed from the inside of the skin. Not all the individuals, however, acquire fat in equal amounts. Thus, of two males taken on October 3 and 9, respectively, one weighed about 5 ounces (138.5 grams), the other 7% ounces (218 grams). And of two females taken at Aspen Valley on October 16, 1915, the respective weights were 5I/2 ounces (156,5 grams) and 8^ ounces (239 grams). Once a "callo" was seen to take a dust bath. At Crane Flat, on June 16, 1915, one of our party was resting in a sandy place where large boulders were scattered about. At his approach all the squirrels had disappeared ; but after a time one — a Golden-mantled — came forth, frisked about, and repeatedh^ "dived through" the little heaps of sand; but it did not roll in the sand. Ground squirrels, generally, are afflicted with fleas, and this and other species have been seen to take this method of ridding themselves of these parasites. About camping and lunching places where summer tourists drop food scraps, copperheads often take advantage of the opportunities afforded to make the getting of food an easy matter. On the summit of Clouds Rest, on August 25, 1915, a "callo" was seen which would come to within three feet or less of a person and take tidbits thrown on the ground. When one of our party offered more material than the squirrel could consume at the moment, it carried the food (in this case dried fruit) in its mouth 176 ANIMAL LIFE IN THE YOSEMITE some distance off, dug a hole in the ground, using the forefeet, thrust the object into the little excavation, then covered the place with earth again, after which it poked small loose stones over the site so as to further disguise it. Probably, as in the case of the California Jay, these caches are temporary affairs, the food being dug up again after a short time and eaten. At Merced Lake four of these squirrels were noted on one occasion gleaning grain scattered on the ground where horses had been fed. The nest of this species is placed in the ground. At Merced Grove one individual had its burrow in open ground close to .several tents. At Crane Flat several of the animals were seen to disappear into burrows surrounded by low brush plants. In the higher altitudes many had their burrows on the open floor of the lodgopole pine forest, sometimes, but not always, beneath rocks. Unfortunately we did not dig out any burrows of this species and no one else seenLS to have done so in the region, so we know nothing as to the arrangement of the burrow system. Presumably it does not differ greatly from those of the California and Belding ground squir- rels; if anything, it might be expected to be simpler in plan. The animal which had its burrow at Merced Grove was seen to choose as nest material some brown wrapping paper which had been left nearby. This was torn into small pieces by use of both the teeth and forepaws and stuffed into the cheek pouches. Then the squirrel disappeared into its burrow, doubtless to add the paper to the lining of the nest chamber. Like the other local squirrels the Golden-mantled Ground Squirrel has only one brood a year ; this brood is produced in the early part of the summer season. Females containing embryos were taken in 1915 on June 12 (two on this date), 14, 26, and 28, the numbers of embryos in these instances being 2, 5, 6, 6, and 5, respectivel)\ The young stay below ground until about one-third to one-half grown. Mr. Dixon saw numbers of young of this species on the east slope of the Sierras above Mono Lake Post Office between altitudes of 7000 and 7800 feet on July 5, 1916. Only one bit of information regarding the enemies of the "callo" was obtained. The droppings of a Mountain Coyote on Colby Mountain were found to contain hair of this species. Taiioe Chipmunk. Eutamias speciosus f rater (Allen) Field characters. — Size mcdiumis for a chipmunk (head and body 4^/^ to 5 inches, tail 31/1 to 3% inches long). (Sec pi. 3c.) Tail bushy, flat-appearing, the long hairs on each side bright brown at bases, then black, with buffy white at tips. Back with nine alternating light and dark stripes, the outermost light stripe on ettch side being con- spicuously pure white; si