Clutch Parameters of Storeria dekayi 75 



Mean clutch size (8.5) was similar to that found in Everglades 

 National Park by Dalrymple et al. (1992), and the samples from both 

 regions had a female - biased sex ratio. Female S. dekayi from Iverson's 

 (1978) northern Florida sample had smaller SVL than females from my 

 study (t = 3.681; df = 10; P < 0.004), but the two samples did not 

 differ significantly in clutch size. Although both mean female SVL 

 (27.3 mm) and clutch size (14.0) from S. dekayi near Lake Erie (King 

 1993) were significantly larger than those of my study (t = 2.12 P = 

 0.05; and / = 7.53 P < 0.00, respectively; df = 38), the difference in 

 SVL was marginal. Mean clutch sizes, 14.9 in Louisiana (Kofron 1979) 

 and 14 in New York (Clausen 1936), are also substantially larger than 

 those for Florida, which supports Fitch's (1985) prediction of smaller 

 clutch sizes in southern latitudes. 



A review of relative clutch mass in snakes indicates that there is 

 a reduction in relative clutch mass among viviparous forms that may 

 reduce the risk of mortality in gravid females (Seigel and Fitch 1984). 

 The cost of lowering relative clutch mass is a reduction of clutch size, 

 offspring size, or both. Resources could limit production of more than 

 one clutch (Bull and Shine 1979), but a large clutch could compensate 

 for a single brood (Seigel and Fitch 1984). Mean relative clutch mass 

 in .V. dekayi from southern Florida was high (0.367) and similar to that 

 (0.372) recorded for S. dekayi from Maryland (Jones 1976). A high 

 relative clutch mass in southern Florida .V. dekayi may compensate for 

 a single small clutch produced each season. 



In northern Florida, females with fully developed conceptuses 

 were recorded from July to September (Iverson 1978). In southern 

 Florida, the earliest date was May (Iverson 1978, my study), and in 

 Everglades National Park captive females gave birth from June to September 

 (Dalrymple et al. 1992). Collectively, the breeding season of Florida 

 populations of S. dekayi (Iverson 1978, Dalrymple et al. 1992, my 

 study) falls within the range of other populations (Fitch 1970, Kofron 

 1979). Further, my results did not indicate a reduction of relative clutch 

 mass, which could facilitate multiple clutch production, in southern 

 Florida S. dekayi. 



CONCLUSIONS 



Clutch frequency of this species in southern Florida has not been 

 determined to date, and multiple clutch production, even if infrequent, 

 has not been excluded. An annual sample of specimens or mark-recapture 

 will best answer this question. Results of my study do not support 

 Fitch's (1970) prediction of multiple clutch production by S. dekayi in 

 the southern part of the range. 



