The Reproductive Biology of Female Sternotherus odoratus in an Alabama Population

Examination of female Sternotherus odoratus in central Alabama revealed that follicular enlargement begins soon after oviposition of the last clutch in July. Yolking of the ovarian follicles continued from August-December, until reaching a size not significantly different from spring preovulatory follicles. Ovulation of the first clutch occurred during late April, and eggs were found in the oviducts from May-July. Central Alabama females have at least 2 clutches per reproductive season, with many laying 3. Mean clutch size was 2.6 (range 1-6). Clutch size was positively correlated to body size, but there was no significant trend for larger females to produce larger oviducal eggs. Females first reached sexual maturity while in the 65-75 mm CL range. Estimated average annual reproductive potential of females laying a maximum of 3 clutches was 7.8 eggs per year.