20 JACK RABBITS OF THE UNITED STATES. 



frequently so light in color as to closely resemble tlie white-bellied 

 Texan Eabbit. 



The Black-tailed Jack Eabbit is found in the Great Basin from the 

 Rocky Mountains west to the Cascade Eange in Oregon and to the 

 Sierra Nevada in California, and from central Idaho and southeastern 

 Washington south to Mexico. Its range extends eastward into west- 

 ern Texas and some distance down the Eio Grande. West of the 

 Sierra it has a most remarkable distribution in a narrow strip along the 

 bottom of the San Joaquin Valley from the Tejon Mountains nearly as 

 far north as latitude 38'\ It gains access to the valley from the Mohave 

 Desert by way of Walker Pass (altitude 5,300 feet) and probably also 

 by the Canada de las Uvas (altitude 4,300 feet). It is distinctly an 

 animal of the deserts and plains and nowhere ascends to very high 

 altitudes. 



In southern Arizona and on the Colorado Desert in California the 

 Texan Jack Eabbit is usually seen singly or in groups of only two 

 or three individuals, while in Kansas, eastern Colorado, and some 

 portions of the (ireat Basin large numbers are often found together. 

 Its abundance or scarcity is usually governed by local conditions — an 

 unusually cold winter, an epidemic or a dry year in which food is 

 8car(.'e, may so reduce its numbers as to make the species appear rare 

 where ordinarily it is abundant. When food supply or other conditions 

 favor its increase it is gregarious to a high degree, and occurs iu 

 immense numbers. 



Forty years ago Dr. George Suckley found these rabbits very abun- 

 dant south of the Boise Eiver, on his tri}) through southwestern 

 Idaho, in September, 1854.' He says: " They are so numerous that our 

 command of «iO men subsisted on them for nearly a week. In a short 

 ride of an hour's duration to see 30 near the trail was nothing remark- 

 able. * • ♦ This hare breeds in great numbers on the vast sage 

 plains at the Soutli Boise EiNer, between it and the Snak«^ Eiver.'' 



More recently, in 1878, MaJ. Chas. Bendire found them in immense 

 numbers in the Payette Valley, in southwestern Idaho, where fully 150 

 were seen together one morning near Payette Eiver Ferry. At this 

 point there was a small grass-covered island to which the rabbits could 

 cr<»ss from the river bank by a bridge. When startled they merely 

 loped away for a few yards and then stopped to ascertain the cause of 

 the disturbance. A writer in 'Forest and Stream'^ states that iu the 

 vicinity of Austin, Nev., .jack rabbits are exceedingly abundant, and 

 that 487 had l)een killed in eight hours by a party of 12 hunters. 



But the Texan Jack Eabbit is most abundant in the southern part of 

 the San Joaquin ^'alley from latitude 37^ southward, where the condi- 

 tions for its existence are so favorable that it is still able to hold 

 its ground in spite of the great numbers annually slauglitered by drives. 



'Pacific Railroad Reports, XII, Book 2, 1*<60, Chap. II, p. U)5. 

 « Vol. XVIII, Apr. 20, 1882, p. 229. 



