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Geology topics

C.K. Dodd

Publications and source records attributed to C.K. Dodd.

At least 55 records · Page 3Linked to original sources
USGS1997

Population structure and the evolution of sexual size dimorphism and sex ratios in an insular population of Florida box turtles ( Terrapene carolina bauri )

Hypotheses in the chelonian literature suggest that in species with sexual size dimorphism, the smaller sex will mature at a smaller size and a younger age than the larger sex, sex ratios should be biased in favor of the earlier maturing sex, and deviations from a 1:1 sex ratio result from maturation of the smaller sex at a younger age. I tested these hypotheses using data collected from 1991 to 1995 on an insular (Egmont Key) population of Florida box turtles, Terrapene carolina bauri. Contrary to predictions, the earlier maturing sex (males) grew to larger sizes than the late maturing sex. Males were significantly larger than females in mean carapace length but not mean body mass. Sex ratios were not balanced, favoring the earlier maturing sex (1.6 males:1 female), but the sex-ratio imbalance did not result from faster maturation of the smaller sex. The imbalance in the sex ratio in Egmont Key's box turtles is not the result of sampling biases; it may result from nest placement. Size-class structure and sex ratios can provide valuable insights into the status and trends of populations of long-lived turtles.

Canadian Journal of Zoology↗
USGS1995

Disarticulation of turtle shells in north-central Florida: How long does a shell remain in the woods?

From 1985 through 1991, I examined and categorized the sequential shell disarticulation patterns of 80 turtle specimens, representing six species and three families, in N-central Florida. Shells were allowed to disarticulate on land under natural environmental conditions. Turtle shells were observed from 5-54 mo. Based on examinations of photos, nine stages of disarticulation were identified. Although it is relatively easy to classify turtle shells into disarticulation stages, the amount of time between death and shell discovery cannot be determined precisely due to individual and species-specific variation in disarticulation rates. Shells do not necessarily pass sequentially through well-defined disarticulation stages. In general, shells of the most commonly observed species, Gopherus polyphemus, Pseudemys nelsoni and P. floridana, routinely remained intact from 12-30 mo, depending on species. Shells usually disarticulated completely by 40 mo or longer.

American Midland Naturalist↗