Onset of Breeding and Breeding Synchrony by Georgia Cottontails

Abstract

Gonception dates were recorded from adult female cottontail rabbits (Syluilagus floridanus) collected from the Piedmont and Coastal Plain physiographic regions of Georgia. The onset of breeding was correlated with late winter temperatures. Some scattered early breeding occurred among rabbits of the Coastal Plain region. However, ie general onset of breeding was similar for both regions. The timing of second periods of first conceptions was also apparently related to late winter temperatures. The onset of breeding and breeding synchrony were statewide in magnitude, thus, emphasizing the possible role of late winter temperatures ( qualitative or quantitative, or both ) as an influence on eastern cottontail population dynamics. Breeding synchrony was not apparent throughout the total breeding season. 544 Journal of Wildlife Mariagement, Vol. 36, No. 2, April 1979 U. S. DEPARTMENT OF COMMERCE. 19&8. C1imatological data: Montana 71(3 8):4S187. . 1969. Climatological data: Montana 72( S8) :41-183. WARBACH, O. 1958. Bird poplllat;ons in relation to changes in lan{l use. J. W;ldl. Mant. 2at 1 ) 2>28. WILLIAMS, A. B. 1936. The composition and dynamies of a beech-maple climax coqnmunity. Ecotl. Monegraphs 6(3):3178. Received for publication July 13,1970. American cardinals, grosbeais, bunffngs, towhees, finches, sparrows, and allies. U. S. Natl. Museum Bull. 237 (pt. 2):&)>1248. Ross, H. H. 1965. A textbook of entomology. 3rd ed. John Wiley & Sons, Inc., New York and London. S39pp. Scorr, O. K., H. H. Scorr, AND G. C. ScoTr. 1966. Sagebrush foothills. Audubon Field Notes 20( 6 ) :657-658. SELBY, S. M. (ed.) 1965. Standard mathematical table!s. 14th ed. lEe Chemical Rubber Co., Cleveland, Ohio. 632pp. Although certain aspects of cottontail reproduction have been studied in past years by numerous authors ( Trippensee 1933, Hamilton 1940, Beule and Studholme 1942, Hosley 1942, Haugen 1942), few studies have been based on animals collected throughout the breeding season. Few data are available in the South concerning the breeding biology of this animal. Heard (1965)) Hill (1966), and Pelton ( 1969a, b, 1970), have reported on various aspects of eastern cottontail reproduction in lThis study was supported by a research grant from the Federal Aid Division of the Georgia Game and Fish Commission. Certain equipment, supplies, and oier funds were also made available from McIntire-Stennis Project No. 11 of the College Experiment Station, Athens, in cooperation with the Georgia Forest Research Council. 2 Present address: Department of Forestry, University of Tennessee, Knoxville. Mississippi, Alabama, and Georgia, respectively. Only in lWissouri has a thorough examination of cottontail reproduction been undertaken ( Schwartz 1942, Wight and Conaway 1961, Conaway and Wight 1962, Wight and Conaway 1962, Conaway et al. 1963, Marsden and Conaway 1963, Evans