NO. OF ANIMALS EST. AGE (MONTHS) 
Reproduction in the Brown Water Snake 
107 
Fig. 2. Size-class structure for spring (April-May) Nerodia taxispilota 
population: (A) Histogram of SVLs: males (solid bars) and juveniles (open bars) 
above the line and females (solid bars) below the line. (B) Probable age-class 
assignments for the same population, redrawn from a cumulative percent plot 
on probability graph paper: juveniles = triangles, males = squares, and females = 
open circles. 
cm SVL) were either dissected or palpated in the field, and none 
contained enlarged follicles or embryos. The larger size at maturity for 
Georgia females may be the result of differences in growth rate or in the 
age at maturity. 
Macroscopic changes in the ovaries of N. taxispilota from central 
Georgia are similar to those described by Betz (1963) for N. rhombifera, 
by Bauman and Metter (1977) and Aldridge (1982) for N. sipedon, and 
by White et al. (1982) for other populations of N. taxispilota. Ovarian 
follicles gradually enlarge with increasing SVL in immature snakes. 
Females in the second full season of activity had ovarian follicles less 
than 3.0 mm in length. The following year follicles had increased to 
between 5 and 9 mm in length. Females are sexually mature at the 
beginning of their fourth full season of activity (approximately 43 
months old). Vitellogenesis occurs rapidly, with follicle lengths often 
exceeding 20 mm prior to ovulation. Ovulation apparently occurs from 
