Foraging mode of the reticulate collared lizard, Crotaphytus reticulatus

摘要

The reticulate collared lizard (Crotapkytus reticulalus) is a large, crotaphytid lizard restricted to the lower Rio Grande Valley of southern Texas and northern Mexico. Our objectives were to determine the foraging mode of this species and test predictions made by other investigators about foraging behavior. We conducted focal observations on 10 male and 10 female lizards in Falcon State Park, Starr County, Texas, to quantify the number of movements per minute (MPM), the proportion of time spent moving (PTM), and the proportion of attacks made on prey items while moving (PAM). We removed foraging movements followed by social displays from the data and recalculated and reanalyzed foraging activity values. With "display" movements removed, there was a significant difference between MPM values and PTM values for males and for the sexes combined, but there was no significant difference in MPM values or PTM values for females. The foraging measures calculated for C. reticalatus, with and without "display" movements removed from the calculations, suggest that it is a "sit-and-wait" ambush forager like its congener C. collaris.