LETTER OF TRANSMITTAL. 
YALE COLLEGE, NEw HAVEN, Conn., 
June 1, 1876. 
Sir: I beg leave to hand you herewith, as a partial report on the zoology of the region trav- 
ersed by your expedition last summer, a list of the mammals and birds observed on the trip. In 
making out this list, I have taken care to give only such species as I actually saw and identified 
either in life or by their remains. I have added a list of such species as have been noticed in the 
immediate vicinity of the Yellowstone Park, combining the observations made by Mr. Merriam, of 
Hayden’s survey, 1872, with my own during the past summer. 
It may not be out of place here, to call your attention to the terrible destruction of large game, 
for the hides alone, which is constantly going on in those portions of Montana and Wyoming through 
which we passed. Buffalo, elk, mule-deer, and antelope are being slaughtered by thousands each 
year, without regard to age or sex, and at all seasons. Of the vast majority of the animals killed, 
the hide only is taken. Females of all these species are as eagerly pursued in the spring, when 
just about to bring forth their young, as at any other time. 
It is estimated that during the winter of 1874~’75 not less than 3,000 elk were killed for 
their hides alone in the valley of the Yellowstone, between the mouth of Trail Creek and the Hot 
Springs. If this be true, what must have been the number for both the Territories? Buffalo and 
mule-deer suffer even more severely than the elk, and antelope nearly as much. The Territories 
referred to have game laws, but, of course, they are imperfect, and cannot, in the present condition 
of the country, be enforced. Much, however, might be done to prevent the reckless destruction of the 
animals to which I have referred, by the officers stationed on the frontier, and a little exertion in 
this direction would be well repaid by the increase of large game in the vicinity of the posts 
where it was not unnecessarily and wantonly destroyed. At one or two points, notably Camp 
Baker, efforts have been made to drive off the skin hunters, and with such success that the officers 
have very fine hunting within easy reach. The general feeling of the better class of frontiersmen, 
guides, hunters, and settlers, is strongly against those who are engaged in this work of butchery, 
and all, I think, would be glad to have this wholesale and short-sighted slaughter put a stop to. 
But it is needless to enlarge upon this abuse. The facts concerning it are well known to most 
Army officers and to all inhabitants of the Territory. It is certain that, unless in some way the 
destruction of these animals can be checked, the large game still so abundant in some localities 
will ere long be exterminated. 
I am, sir, very respectfully, your obedient servant, 
GEO. BIRD GRINNELL. 
Col. Wu. LUDLOW, 
Chief Engineer Department Dakota, St. Paul, Minnesota. 
