REPRODUCTIVE CYCLE OF THE SIDEWINDER, CROTALUS CERASTES (SERPENTES: VIPERIDAE), FROM CALIFORNIA

摘要

Reproductive tissue was examined from 159 museum specimens of Crotalus cerastes from California. Males follow a seasonal testicular cycle with sperm produced June-October; regressed testes were present March-June and October. Timing of this cycle is similar to that of other North American rattlesnakes. Sperm were present in the vasa deferentia March-October. Mean litter size for 26 C. cerastes was 7.96 +- 2.9 SD, range = 3-14. The number of females that were gravid (enlarged follicles > 8 mm or oviductal eggs) during the April to August period of female reproductive activity was 28/53 (53%). The presence of females with early yolk deposition in April and May when other females were gravid suggests more than one reproductive season is needed to complete yolk deposition.