Meeting Abstract

P2.20  Wednesday, Jan. 5  Site fidelity and geographic variation in home-range ecology of side-blotched lizards, Uta stansburiana SCOULAR, K.M.; ZANI, P.A.**; Lafayette College; Whitman College zanipa@whitman.edu

We studied the spatial ecology of side-blotched lizards in eastern Oregon to test for site fidelity of individuals. Over three years we collected 3675 coordinates from 51 males and 60 females during the breeding season. We detected significant variation in individual home-range sizes and home-range overlap between years suggesting that spatial relationships are variable. However, we also found strong year-to-year site fidelity in location of lizard home ranges regardless of sex, which may be a consequence of relatively high inter-annual survival in this population. Thus, lizards appear to settle in one location as they mature and move very little as adults. By combining these data with data from eight other previously studied Uta populations, we tested for the effects of latitude, lizard sex, and population density on home-range size. We found significant geographic variation in home-range size of Uta. Latitude has the most consistent (and positive) effects, but population density also plays a role (negatively) in determining home-range size, which is especially apparent at sites for which long-term data are available (i.e., west Texas, central California). We conclude that fluctuations in ecosystem productivity are likely important determinants of population density and spatial ecology of lizards.