The Western Slimy Salamander (Plethodon albagula) in central Texas is known from both surface and cave environments. Threshold species, such as P. albagula, may be excellent candidates to study potential differences in life-history traits during the evolutionary transition from surface into subterranean habitats. We conducted a 29-mo mark-recapture study of a surface and a cave population in Bell County, Texas, USA, to determine whether these populations differed in body size, growth rate, age at sexual maturity, and life span. We employed a growth model to estimate growth rate, age at sexual maturity, and life span, and an open population model to estimate population size, density, catchability, and survival rates. Salamanders were smaller on average and reached a smaller maximum size in the surface population compared to the cave population, which was skewed toward larger, older individuals. Growth trajectories were similar between populations, but the cave population reached sexual maturity faster (0.9–1.4 y) than the surface population (1.5–2.2 y). Survival rates were similar between populations. Although population size estimates were 10 times higher for the surface compared to the cave population, densities were similar between sites suggesting that habitat availability alone could explain population size differences. Plethodon albagula exhibits plasticity in growth, body size, and development, which may be adaptive and a function of extreme variation in surface environmental conditions. Subterranean habitats may be important for the long-term persistence of local populations, which may persist for years in subterranean habitats.
|Original language||English (US)|
|Journal||Herpetological Conservation and Biology|
|State||Published - 2015|