Macaw abundance in relation to human population density in the western amazon basin

Abstract

We assess whether macaw population size varies with human population density in the western Amazon basin. Several factors, including collecting baby macaws for the pet trade, increase dramatically in areas with higher human population densities in the Amazon basin. We use a ‘quasi-experimental’ design to determine population size variation of four Ara macaw species in two regions of the Peruvian and Colombian Amazon, each having a low human population density site (~7–12 villages, 100–150 people per village) and high human population density site (30–50 villages each) for comparison. In region one, the abundances of all four species of Ara macaws were negatively related to human density. However, this trend held for only two of the four Ara species in region two. We discuss the relative importance of various factors (seasonal fruit abundance, overharvest of macaws for protein or the pet trade, and palm tree harvest) to the patterns observed, as well as the policy and management implications of these patterns.