Effects of Human Land Use on Prey Availability and Body Condition in the Green Anole Lizard, Anolis Carolinensis

Abstract

—Lizards frequently occur in disturbed habitats, yet the impacts of human activity on lizard biology remain understudied. Here, we examined the effects of land use on the body condition of Green Anole lizards (Anolis carolinensis) and the availability of their arthropod prey. Because human activity generally alters abiotic and biotic habitat features, we predicted that areas modified by humans would differ from areas with natural, intact vegetation in arthropod abundance and biomass. In addition, because biological communities in high use areas are often relatively homogenized, we predicted that higher human land use would result in lower prey diversity. Regardless of land use, we also predicted that areas with greater prey availability and diversity would support lizards with higher body condition. We studied anoles in six plots with varying levels of human modification in Palmetto State Park in Gonzales County, Texas. We quantified arthropod abundance, biomass, and diversity in each plot via transects and insect traps. We also determined lizard body condition using mass:length ratios and residuals, fat pad mass, and liver lipid content. We found that, although arthropod abundance did not differ across plots, arthropod biomass was higher in natural than in disturbed plots. Diversity indices showed that the plots varied in their arthropod community diversity, but not in relation to disturbance. Female (but not male) lizard body condition differed across plots, with body condition higher in natural plots than disturbed plots. Together, these results suggest that land use is associated with lizard body condition, but not through a direct relationship with prey availability.