Estimating Survival of Song Bird Carcasses In Crops and Woodlots

George M. Linz, National Wildlife Research Center
David L. Bergman, U. S. Department of Agriculture
William J. Bleier, North Dakota State University

Document Type Article

Published in The Prairie Naturalist 29(1): March 1997.

Abstract

Estimates of non-target animal mortality due to the effects of agricultural pesticides may be biased by the removal of carcasses by scavengers. We placed intact songbird carcasses in ripening sunflower fields in late-summer, and in harvested corn fields and woodlots in early spring to assess carcass removal by scavengers. Removal curves differed among the three habitats (P < 0.001). One day after placement, 58% of carcasses persisted in the sunflower fields, whereas 82% and 90% remained in the corn fields and woodlots, respectively. Our results suggest that survival times for carcasses are variable and dependent on habitat and, perhaps seasonal factors. In most cases, searches for carcasses should be conducted within one day of the pesticide application.