ABSTRACT

Many aspects of salamanders’ biology and ecology have been examined; however, few studies have examined trade-offs in life history traits. One common trade-off in other animals, for example frogs and mammals, is the relationship between fecundity and parental investment (number of eggs/offspring, clutch size, mature ova, and size of eggs/offspring). Whether these trade-offs are held in salamanders is poorly known.

The purpose of this study was to compile data sets on salamander reproductive traits from various credible sources (Petranka, Mitchell and Gibbs, Dodds Jr.) to understand the variation/trade-offs among salamander species. Histograms, linear regression analyses, and Mann Whitney U tests were conducted to determine overall variation in life-history traits, to assess whether life-history traits varied significantly across common Southeastern genera, and to observe correlation among the reproductive life-history traits for salamanders. The histograms displayed a large variation for each trait. The box plots illustrated significant differences among the traits for Plethedons, Desmognathus, Eurycea, and Ambyostoma. Moreover, through the linear regression lines, relationships were established with clutch size-egg size and mature ova-egg size being statistically significant, and eggs per nest-egg size being statistically insignificant potentially because eggs per nest is not an effective measure of individual female reproductive output.