The Relationship of Precipitation and Black‐Tailed Jack Rabbit Populations in Kansas

Abstract

Populations of black-tailed jack rabbits (Lepus californictis ssp.) have increased to near plague proportions at various times in many western states. The limited records show that western Kansas has experienced two population increases of such proportions and that both have occurred during droughts (Wooster 1935, Carter 1939, Bronson 1957). The subspecies present in this region is L. c. vmelanotis. The economy of western Kansas is principally agricultural and, when large numbers of these animals are present, excessive crop damage may result. Reports of crop damage in 1954-'55 and 1955-'56 reached proportions unheard of since the drought of the mid-1930's. Rabbit (Irives, common methods of destruction in the 1930's, were held again in many western counties. Unconfirmed reports stated that as many as a thousand or more jack rabbits were killed on some of these drives. A study of the ecology of this hare, its population fluctuations, reproduction, habits and economic effects was begun in July of 1956 and is continuing. This paper presents data on the changes in the number of jack rabbits on a study area in relation to the termination of a five-year drought (19521956). The possible relation between the data collected on the study area and the long-term population fluctuations of this species in Kansas is explored. Thorough studies of the ecology of L. californzicuts ssp. have been made in Arizona by Vorhies and Taylor ( 1933) and in California by Lechleitner (1956). Woodbury (1955) charted anl annual cycle of these animals in Utah.