Distribution and Relative Abundance Patterns of Columbids in Puerto Rico

Abstract

From July 1986 to January 1989 standardized call and sight counts were conducted to examine the distribution and relative abundance patterns of Plain Pigeons (Columba inornata), White-crowned Pigeons (C. leucocephala), Scaly-naped Pigeons (C. squamosa), Zenaida Doves (Zenaida aurita), White-winged Doves (Z. asiatica), Mourning Doves (Z. macroura), Common Ground-Doves (Columbina passerina), Ruddy Quail-Doves (Geotrygon montana), Key West Quail-Doves (G. chrysia), and Bridled Quail-Doves (G. mystacea) during the different seasons of the year in the dry, moist and wet zones of Puerto Rico. The relative abundance of all columbids peaked during the spring-summer period (March-August) in the life zones. The relative abundance of Zenaida Doves and Common Ground-Doves peaked during the spring-summer, but a second noticeable peak occurred during the fall (September-November) in the dry zone. The seasonal patterns of relative abundance were detectable at local as well as at regional scales of sampling, regardless of the observer involved and the counting technique applied. The detected patterns are not considered to be either the result of sampling error or of statistical artifacts. The seasonal patterns of relative abundance in the three major life zones probably represent the most general and repeatable aspect of the population dynamics of columbids in the island. Two components of the environment of columbids are considered of principal importance in determining their seasonal relative abundance in the life zones: (1) rainfall in the dry zone, and (2) fruiting phenology of key tree species in the moist and wet zones.