366 ANNUAf. RKPORTS OF DKPAKTMKNT OF AGRICULTURE. 



Service for piiI)lic'atioiK and a ]ar<;e mamiscrijit niaj) showing the life 

 zones of the "Yellowstone National ]*ark and the re<;ion adjoininfj: it 

 on the soutii was prepared for the use of the National Park Service. 

 Lists of a few characteristic; l)irds and mammals of Mount IJainier 

 National Park have alread}' been i)iihlished by the National Park 

 Service in its circidai- of information, and, as already stated, a detailed 

 report on the re<2:ion is well advanced in preparation. 



i RELATION OF RODENTS TO FOREST PRODUCTION. 



Progress was made in experiments being conducted to secure in- 

 formation concerning damage to crops and forage by injurious ro- 

 dents, instituted in the spring of 1918 in several western States, 

 notably xVrizona and Colorado. By means of quadrats established 

 on grazing areas, some of these plats being fenced and others un- 

 fenced, the damage inflicted by the rodents which abound there is 

 measured. A preliminary report on the results of these investiga- 

 tions is in preparation. A department circular (No. 59) entitled 

 " Field Studies of Mammalian Life Histories.'" which outlines the pro- 

 cedure to be followed in studying the habits of these important ani- 

 mals in order to obtain the best results, was issued in October. 



BIG-GAME AND BIRD RESERVATIONS. 



Federal big-game and bird reservations in charge of the Biological 

 Survey are now 75 in number. Four are big-game preserves, 70 are 

 bird reservations, and 1, the Niobrara, created as a bird reservation, 

 is used for both birds and big game. Included in the number is a 

 small bird reservation near Fort Myers, Fla., of two islands contain- 

 ing rookeries and breeding grounds of several species of herons, 

 established by Executive order of July 1, 1920. and known as the 

 Caloosahatchee bird reservation, in the river of the same name. On 

 June 30, 1920, the big-game reservations contained a total of 427 

 buffalo, 384 elk. 60 antelope, and 27 deer, an increase in each species 

 OA'er last year. The total number of buffalo now in the Government's 

 various herds exceeds a thousand head, of which about half are under 

 the charge of this department. 



The boundaries of the Niobrara Reservation were modified during 

 the year by the inclusion of a narrow strip of bottom land on the 

 west boundary along the Niobrara River.- A bill affecting the 

 boundaries pi tlie Klamath Bird Reservation, approved on May 27. 

 1920, among other things authorizes the Secretary of the Interior 

 to determine which lands are chiefly valuable for a bird preserve 

 and which are cliiefly valuable for agriculture, and to eliminate and 

 open to settlement the agricultural areas. The measure is likely to 

 result in the modification of the southern boundaries of the reserva- 

 tion and in tiie elimination of swamp lands, which, however, have not 

 been utilized by the birds for several years. 



During the summer an investigation was made by a representative 

 of the bureau, in cooperation with the secretary of the American 

 Bison Society, for the purpose of selecting a tract in eastern Oregon 

 suitable for a refuge for sage grouse and antelope, and as a result 

 one was selected east of Warner Lake and extending from Lake 

 County, Oreg.. to Washoe Count3% Nev.- Some opposition to the 



