Growth and reproductive output in two temporal scale populations of the endangered dand-dune lizard Liolaemus multimaculatus from Argentina

Abstract

The understanding of the potential impacts of environmental change on population dynamics is essential for the conservation of endangered species such as the endemic sand-dune lizard Liolaemus multimaculatus from Argentina. Employing skeletochronology, we determined the age at sexual maturity, maximum life span, and age-specific body length of two populations in geographic proximity but at different times (one in 1915 and the other in 1993−2006). We also calculated the relative reproductive time (RT) and net reproductive rate (R₀) using reproductive data from the literature. We found that L. multimaculatus showed a fast life-history pattern characterized by small-size, multiple clutches per year, and a short life span. This species displays the shortest maximum life span (6 a) reported in Liolaemus compared to other species studied by skeletochronology. The sand-dune lizard populations show a delay in sexual maturity and a decreased RT, proportion of adult life, and R₀ over the last 80−90 years probably related to the increase in environmental temperatures. If this trend continues could affect the life history traits becoming a serious threat for some populations, in particular those under anthropogenic disturbances.