Common Field-mouse (Microtus pennsylvannicus modestus)
Recorded by Vernon Bailey from Lower Geyser Basin in the Park.
Long-tailed Vole (Microtus mordax)
Vernon Bailey records this from various surrounding localities, also from Tower Falls. Doubtless it is generally distributed. This is the bobtailed, short-eared, dark gray mouse that is found making runs in the thick grass, especially in low places.
Big-footed Vole (Microtus richardsoni macropus)
Not yet taken in the Park, but found in surrounding mountains, therefore probable.
Muskrat (Fiber zibethicus osoyoosensis)
Common and of general distribution.
Mole-gopher or Gray Gopher (Thomomys talpoides)
A Gopher of some kind abounds in the Park. I assume it to be this.
Rocky Mt. Jumping Mouse (Zapus princeps)
Found in all the surrounding country, and recorded by E. A. Preble from near Yellowstone Lake.
Yellow-haired Porcupine (Erethizon epixanthus)
Somewhat common in the pine woods on the Continental Divide.
Coney, Rock Rabbit, Pika, or Calling Hare (Ochotona princeps)
Abundant in all slide rock.
Rocky Mt. Cottontail (Sylvilagus nuttalli grangeri)
Plentiful about Gardiner and in some of the lower regions of the Park, but not general.
Snowshoe Rabbit (Lepus bairdi)
Common and generally distributed.
White-tailed Jack Rabbit (Lepus campestris)
Common and generally distributed.
Mountain Lion, Cougar or Puma (Felis hippolestes)
In 1897 it was considered extremely rare; probably not more than a dozen were then living in the Park; since then it seems to have increased greatly and is now somewhat common in the mountainous parts. Their numbers are given officially at 100 in 1912.
Canada Lynx (Lynx canadensis)
Common.
Bobcat or Mountain-cat (Lynx uinta)
Somewhat common.
The Big-tailed Fox (Vulpes macrourus)
Common.
Timber Wolf (Canis occidentalis)
Very rare, noticed only at Hell Roaring Creek and Slough Creek. On August 25, 1912, Lieut. M. Murray saw two in a meadow two miles southeast of Snow Shoe Cabin on Slough Creek. They were plainly seen in broad daylight; and were nearly white.
Coyote (Canis latrans)
Abundant everywhere, although officially reckoned they numbered only 400 in 1912.
Otter (Lutra canadensis)
Common, particularly around the Lake and the Canyon.
Mink (Lutreola vison energumenos)
Common.
Long-tailed Weasel (Putorius longicauda)
Said to be found. I did not see any.
Short-tailed Weasel (Putorius cicognanii)
Included because its range includes the Park.
Marten (Mustela caurina)
Found throughout the Park, but not common.
Pekan or Fisher (Mustela pennanti)
Rare. Gen. G. S. Anderson tells me that in the early '90's he took the skin of one from a poacher.
Wolverine (Gulo luscus)
Of general distribution, but not common.
Northern Skunk (Mephitis hudsonica)
Rare, but found at Mammoth Hot Springs and Yancey's.
Badger (Taxidea taxus)
Common.
Raccoon or Coon (Procyon lotor)
Said to occur. Fifteen years ago at Gardiner I was shown one that was said to have been taken in the Park, but it was not certain.
Grizzly Bear (Ursus horribilis)
Common. The official count gives 50 in 1912.
Blackbear (Ursus americanus)
Abundant and increasing. The official count gives 100 in 1912.
Common or Masked Shrew (Sorex personatus)
Never taken, but included because its known range surrounds the Park.
Marsh Shrew or Water Shrew (Neosorex palustris)
Probably occurs there, since its known range surrounds the Park.
Long-eared Bat (Corynorhinus macrotis pallescens)
A few were seen in the Devil's Kitchen, Mammoth Hot Springs, and one sent to the Biological Survey for identification. This is the only Bat taken, but the following are likely to be found, as their known range surrounds the Park:
Little Brown Bat (Myotis lucifugus)
Silver-haired Bat (Lasionycteris noctivagans)
Big Brown Bat (Eptesicus fuscus)
Great Hoary Bat (Nycteris cinereus)