MAMMALS OF THE YELLOWSTONE NATIONAL PARK 



ERNEST SETON THOMPSON. 



The rigid preservation of all kinds ot 

 wild life, in the Yellowstone Park, has left 

 it the one spot in the Union, perhaps, 

 where pristine conditions continue and 

 where we can see for ourselves, to-day, 

 what the great West was like, in the past 

 generation. 



This was what was intended when the 

 park was reserved, and it is a magnificent 

 idea, carried out in a worthy manner. But 

 to the naturalist, the absolute prohibition 

 of collecting is somewhat embarrassing 

 and leaves the list of small mammals with 

 numerous gaps and uncertainties. 



Thanks are due to Dr. J. A. Allen, of the 

 American Museum, New York, for assist- 

 ance in identifying the smaller species. And 

 to Capt. George S. Anderson, U. S. A., the 

 retiring Superintendent of the Park, for 

 looking over and annotating my list. His 

 remarks are quoted over his initials. ■ 



Several quotations from Lieut. Elmer 

 Lindsley's Report (Dept. of the Interior, 

 1897), appear over his name. Valuable as- 

 sistance has also been received from Dr. C. 

 Hart Merriam's Biological Reconnaissance 

 of South Central Idaho. (U. S. Dept. of 

 Agriculture, 1891.) 



Bats: Numerous small bats were seen, 

 but no specimens were obtained. " At the 

 Devil's Kitchen, Mammoth Hot Springs, 

 large numbers may be seen." G. S. A. 



Shrews, Moles: No doubt several spe- 

 cies occur in the park: I did not see any. 



1. Rock Chuck or Marmot {Arctomys 

 Haviventer Aud. and Bach). Rockchuck 

 or Marmot very abundant in rocky hill- 

 sides in certain localities. Notably about 

 Yancey's, where its loud shrill alarm 

 whistle is heard all day long. " Numerous 

 all over the park, but especially so near 

 travelled roads and often changes its hab- 

 itat." G. S. A. 



2. Upland Prairie Dog (Cynomys ludovi- 

 cianus Ord.). Abundant on ttu lower Yel- 

 lowstone, but I did not see it in or near the 

 park. Capt. Anderson says: " I have seen 

 a few prairie dogs near the North line of 

 the Park and I think inside the line." 



3. Picket-pin Gopher or Ground Squir- 

 rel (S pernio phihis armatas Kenn). Swarms 

 in certain localities as about Mammoth 

 Hot Springs and on the flat about Yancey's 

 house. The species was identified for me 

 by Prof. D. G. Elliot. " Numerous in all 

 open places." G. S. A. 



4. Striped Gopher (S pernio hhilus lin- 

 eatus pallidus Allen). I feel almost cer- 

 tain that I saw this species on the Gardiner 

 River flat after leaving Mammoth Hot 

 Springs, on the Yancey trail. 



5. Big Golden Chipmunk (Tamias later- 

 alis cinerascens Allen). This is the very 



large chipmunk that is so conspicuous 

 about Golden Gate and thence South along 

 the road to Norris. " Common all over the 

 Park." G. S. A. 



6. Little 4-striped Chipmunk (Tamias 4- 

 vittatus luieiventris Allen). Very abundant. 

 On August 8th while driving with Mr. A. 

 E. Brown from Norris to the Mammoth, 

 we saw on the road, within 20 miles, at 

 least 1,000 chipmunks chiefly of this species; 

 they were as often in groups as singly. In 

 one place we saw 9, another 10, another 8, 

 another 11, another 20, another 28, in one 

 place 30, all within a few feet of one another. 

 They seem to enjoy scampering in the dust, 

 but the prime attractions were the scattered 

 oats and the fact, that all along each side 

 of the road was a continuous pile of long 

 and small trees, left by the road-makers, 

 making the roads very convenient to ex- 

 ceptionally good harbors of refuge. The 

 species was identified for me by Prof. Elliot. 

 " Plentiful; tame; a nuisance at all my sta- 

 tions. Will eat out of your hand in a week's 

 acquaintance." G. S. A. 



7. Richardson's Red Squirrel (Sciurius 

 richardsoni Bachman). Abundant through- 

 out the Park. 



8. Northern Flying Squirrel (Sciuropterus 

 sabrimis Shaw). Said to be common. Not 

 seen by me. " Have seen only 1 or 2. 

 Don't believe them common." G. S. A. 



9. Beaver (Castor canadensis Kuhl). 

 Abundant throughout the Park, and doubt- 

 less increasing. Beaver lake is the most 

 imposing example of beaver work that the 

 Park can show — it is a lake formed by a 

 dam 600 yards in length. In the October 

 number of Recreation I gave a descrip- 

 tion of the Beaver ponds near Yancey's. 

 I now reproduce a chart of the dams and 

 canals. " Everywhere increasing rapidly." 

 G. S. A. 



" The beaver are quite numerous in the 

 park, and inhabit the following localities: 

 Gardiner river, near the Post, Lupine and 

 Blacktail Creek, Elk Creek, the Lamar 

 River, Slough Creek. Cache Creek, Soda 

 Butte Creek, a few in Pelican Creek, the 

 Upper Yellowstone. Thoroughfare Creek, 

 a few in Barlow's Fork of Snake River, some 

 in Falls River meadows, a few about Sho- 

 shone Lake. There is a flourishing colony 

 in Nez Perce Creek, a large one near the 

 mouth of Magpie Creek, and a goodly num- 

 ber in the Gibbon River near Norris. There 

 are some in Cascade Creek and in the lake, 

 and all the creeks that drain into the Gar- 

 diner River above the falls. The lower 

 beaver dam, opposite Obsidian Cliff, has 

 been rebuilt. I think there are more 

 beaver in the Park now than at any time 

 within the last 6 years, and if unmolested 

 they will rapidly increase. Their protec- 



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