Meeting Abstract

P1.66  Thursday, Jan. 3  Behavioral ecology of a northern population of side-blotched lizards (Uta stansburiana): home range and habitat use ZANI, P.A.*; FINAN, E.S.; Lafayette College; Hamilton College zanip@lafayette.edu

We studied the behavioral ecology of a population of side-blotched lizards (Uta stansburiana) in eastern Oregon. Our goals were to determine 1) the degree to which males and females exhibit home-range overlap during the breeding season, and 2) the habitat characteristics that are favored (or avoided) in this population. We marked 70 lizards (31 males, 39 females) in an area 230 m x 70 m (~1.6 ha). From mid-May to late June 2007 we conducted daily systematic censuses to identify active lizards. In addition, we conducted 79 focal observations (up to 30 minutes each) on 44 resident lizards. Our efforts resulted in 1120 observations during the breeding season. To analyze home ranges we included data from 20 males and 20 females for which we had six or more (up to 54; median = 23.5) observations. All animals overlapped with one or more lizard of each sex. Males overlapped equally with other males (4.2 � 2.15, 1-9; mean � 1S.D., range) and females (4.2 � 2.13, 1-10). However, females overlapped more frequently with males (4.0 � 2.05, 1-8) than females (2.8 � 1.52, 1-6). While males did interact aggressively if they encountered other males, it did not appear that males strongly defended an area within their home range. Furthermore, we saw no evidence that females engaged in social interactions with other females. In addition to collecting coordinate data, for each observation we characterized the substrate, brush cover, and distance to the nearest cliff. Our data indicate that lizards clearly favor rocky areas and areas near the tops of cliffs as centers of activity. Lizard activity does not correlate to areas of loose soil or dense brush cover. Overall, the home-range ecology and habitat use of northern Uta appears to be similar to that of more southern populations.