Age, growth and survival rate in two populations of Darevskia derjugini (Nikolsky, 1898) from different altitudes (Squamata: Sauria: Lacertidae)

Abstract

We investigated age structure, age at sexual maturity, lifespan, growth and survival rate and adult life expectancy (as demographic life-history traits) as well as body size of two Darevskia derjugini (Artvin lizard) populations from different altitudes, using skeletochronology. Our findings indicated that age upon attaining sexual maturity was two or three years in the low-altitude population (Fındıklı) while it was three years in the high-altitude population (Murgul) for both sexes. The maximum longevity was seven years in the high-elevation site while it was six years in the low-elevation site. As reported for many lizards, we found a significant positive relationship between age and body size within each sex of Artvin lizard at both altitudes. High- and low-altitude populations did not differ in age structure, survival rates, adult life expectancy and body size. Rather than the effect of altitude, which is hard to compare without replication of other low and high altitude populations, the fact that these two populations have similar growth rates and the similarity of local conditions (food availability and predator density) may indicate similarity between the two regions.