POPULATION METRICS FOR THE PERCEIVED COMMON AND ABUNDANT PENINSULA COOTER AND FLORIDA RED-BELLIED COOTER IN A FLORIDA, USA, SPRING ECOSYSTEM

The Peninsula Cooter (Pseudemys peninsularis) and the Florida Red-bellied Cooter (P. nelsoni) are considered common throughout much of their respective ranges. Both species occur in numerous habitats in Florida, USA, including rivers, lakes, ponds, freshwater springs, and spring runs. We sampled Peninsula Cooter and Florida Red-bellied Cooter populations from 1999 through 2015 as a component of a long-term freshwater turtle assemblage monitoring study in a protected central Florida spring-run complex that experiences high levels of human recreation. For each species, we: (1) generated relative abundance and population estimates; (2) quantified survivorship and recruitment; and (3) calculated sex ratios, density, and biomass. Population estimates were similar for both species, and sex ratios were approximately 1:1 for both species, whereas density and biomass estimates were higher than previous studies. Recapture rates were moderate for each sex of both species. Apparent survivorship was higher in males than females for both species but lower than from comparable studies. Sensitivities for both species suggest adult female mortality followed by the percentage of females breeding had the greatest influence on population growth. Stable populations of common species are important in maintaining overall community integrity. Therefore, it is prudent to promote the conservation of common species to protect ecosystem structures and services.