Perch restriction and seasonal effects on aggression in the iguanid lizard anolis carolinensis

Available perching space and season interact to influence aggression levels in male Anolis carolinensis. Ninety four pairs of adult males were tested over a six-month period (June-November) 1985 in a large enclosure containing either a long or short perch. Aggression levels were recorded for each individual over a three hour period.

Results indicate that both perch availability and season affect aggression levels in males of this species. Animals on the small perch during the months of June, July, and August demonstrated significantly higher levels of aggression than all other lizards. Also, perch sharing was common and often occurred rapidly after an agonistic interaction suggesting this may not be an uncommon event in nature. The data lead me to address the issue of territoriality as it pertains to male Anolis carolinensis and lizards in general. Although most of the lizards in the genus Anolis are described as territorial, I present a theoretical framework in which the "territoriality" of lizards may be regarded as a highly flexible behavioral tactic adaptive only in specific contexts. The broad characterization of a genus or even a species as territorial is misleading.