THE RELATIONSHIP BETWEEN WHITE-WINGED DOVE CALL-COUNT SURVEYS AND NEST DENSITIES IN AN URBAN-ENVIRONMENT

Call-count surveys have been used for determining white-winged dove (Z enaida asiatica) distribution and abundance in the southwestern United States and Mexico. However, few studies have investigated survey vali dity. We compared call-count survey results to actual nests found in u rban habitats in San Antonio, Texas in 1991-1992. Thirty-five and 40 i ndividual call-count listening points were randomly chosen from 23 8-k m transect lines in 1991 and 1992, respectively, and 0.2-ha nest-searc h plots were established on each point. Number of calls heard during t he peak week of calling in each year were compared to number of nests found on each plot in the preceding survey week using simple linear re gression. Call-counts heard appeared to have predictive ability to num ber of nests in 1991 (R-2 = 0.73, P < 0.001), but not in 1992 (R-2 = 0 .146, P = 0.009). When 1 high nest-density point was eliminated from 1 991 data, results were poor (R-2 = 0.0, P < 0.7). Call-count surveys w ere poorly related to number of nests found in urban environments and may not be an appropriate breeding population indicator, except where white-winged dove nest density is high (>50 nests/ha). We suggest usin g nest plots to evaluate population trends in white-winged doves.