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C.K. Dodd

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

At least 37 records · Page 2Linked to original sources
USGS2003

Estimation of Flattened Musk Turtle (Sternotherus depressus) survival, recapture, and recovery rate during and after a disease outbreak

We estimated survivorship, recapture probabilities and recovery rates in a threatened population of Flattened Musk Turtles (Sternotherus depressus) through a disease outbreak in Alabama in 1985. We evaluated a set of models for the demographic effects of disease by analyzing recaptures and recoveries simultaneously. Multiple-model inference suggested survival was temporally dynamic, whereas recapture probability was sex- and age-specifc. Biweekly survivorship declined from 98-99% before to 82-88% during the outbreak. Live recapture was twice as likely for male turtles relative to juveniles or females, whereas dead recoveries varied only slightly by sex and age. Our results suggest modest reduction in survival over a relatively short time period may severely affect population status.

Journal of Herpetology↗
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↗