Patterns of temporal variation in growth rate from a mainland population of Anolis nebulosus (Squamata: Dactyloidae), in the Mexican Pacific Coast

In this study we used three nonlinear regression models: Von Bertalanffy, logistic-by-length, and logistic-by-weight to describe the pattern of growth of hatchling, juvenile, and adult of the lizard Anolis nebulosus in a tropical dry forest near of the Mexican Pacific coast during a period of 1989 and 1990. Von Bertalanffy and logistic-by-length models showed the best fit to the growth data for males and females of three age classes from marked and recaptured lizards in these years. The characteristic parameter of growth (r) and asymptotic growth (A₁) extracted from these models indicated that males grow faster than females, but the latter reach a slightly larger size than males. The growth curves revealed that males reach minimum size at sexual maturity at 35 mm in snout-vent length (SVL), at an age of seven months, while females reach sexual maturity at 37 mm of SVL at nine months. Comparisons of growth rate between wet and dry seasons and years revealed that hatchlings and juveniles of both sexes had higher growth during the wet season for both years. Although there was no significant variation between measured environmental variables or in the food availability, the weight of evidence suggests that environmental variation has an influence on the growth of A. nebulosus of this population. Results indicate that variation on growth patterns observed may result from a combination of environmental factors, such as food availability, predation pressure and some reproductive characteristics as size at sexual maturity and size of hatchlings at birth.