Life history of the Marbled Whiptail Lizard <em>Aspidoscelis marmorata</em> from the central Chihuahuan Desert, Mexico

Abstract

The life history of a population of marbled whiptail lizard, Aspidoscelis marmorata, was examined from 1989 to 1994 in the sand dunes of the Biosphere Reserve of Mapimí, in Northern México. Lizards were studied using mark-recapture techniques. Reproduction in females occurred between May and August, with birth hatchlings matching the wet season in August. Reproductive activity was highest in the early wet season (July). Males and females reached adult size class at an average age of 1.7 years and 1.8 years, respectively. Body size of males attained an asymptote around 90 mm snout-vent length and females around 82 mm snout-vent length, at an age of approximately 3.6 years and 3.0 years, respectively. The density varied from 7 to 85 individuals / 1.0 ha. The Mexican population had late maturity, relatively long life expectancy, and fewer offspring. Overall, the observed data for A. marmorata and the expectations of life history theory for a late maturing species (K-rate selection) are in agreement.