Home-Range Size and Overlap in Sceloporus undulatus erythrocheilus (Reptilia: Iguanidae)

Abstract

A population of the rock-inhabiting lizard, Sceloporus undulatus erythrocheilus, was studied over two activity seasons in the eastern Colorado foothills. The convex polygon method was used to determine home range and figures were adjusted to eliminate sample size bias. Ninety-seven lizards (53 8 and 44 9) were captured. On the basis of ten or more observations, resident adults (= 50 mm snout-vent length) had an average home-range size of 826 m2 for 12 males and 363 m2 for 9 females. Male home-range size decreased significantly after the breeding season. The large degree of male home-range overlap (52%) suggests that home range is not equal to territory in this population. A promiscuous mating system is implied from the overlap of male and female home ranges and from behavioral notes.