R3 PM Application of Spatially Explicit Techniques in Ecological Risk Assessment
Thursday, 17 November 2005: 1:50 PM - 5:30 PM in Ballroom 3

(COL-1115-318045) Landscape Scale Assessment of Contaminant Effects on Cavity-nesting Birds.

Colestock, K¹, Gervais, J¹, Fair, J², Ryti, R³, Gonzales, G^{1, 2}, ¹ Utah State University, Logan, UT, USA² Los Alamos National Laboratory, Los Alamos, NM, USA³ Neptune and Company, Inc., Los Alamos, NM, 87544

ABSTRACT- We studied the effects of contaminants on reproductive parameters of a western bluebird (Sialia mexicana) population nesting across a contaminant gradient at Los Alamos National Laboratory, New Mexico. Bluebirds are regional migrants, so we restricted our investigation to juveniles to explore local contaminant uptake. We evaluated reproductive success in relation to soil contamination levels in the individual home range. Home range size was determined using foraging observations, and the observed home ranges were correlated to measured and interpolated soil contaminant data. Eggs were analyzed for PCBs, heavy metals, and radionuclides and prey remains were collected from study nests to determine the potential contaminant uptake from the home range. We also measured nesting success, fledging success, and fluctuating asymmetry of nestlings. These results are compared to contaminant concentrations and to predicted hazard quotients from a spatial exposure model. This provides a comparison of measured and modeled exposure information and also provides a validation of the modeled effects information with field data.

Key words: contaminants, western bluebird, home range, spatial model