Patterns of Activity, Flocking, and Habitat Use in Parrots of the Peruvian Amazon

We explored patterns of flight activity, flocking, and habitat use in a diverse community of parrots in an Amazonian lowland forest. Parrots were most active just after sunrise with a second peak of flight activity following a mid-day lull. Brotogeris spp. were exceptional, being most active in the early afternoon. Among the nine genera studied, we observed marked differences in where the birds flew relative to the canopy. Body size was a poor predictor of flight height, although it was strongly and inversely correlated with flock size. Most parrot species flew in groups of one to four individuals, suggesting that mated pairs are stable and that family groups remain together post-fledging. Flocks were exclusively monospecific except when the birds were foraging in trees or eating soil at clay licks. These forest-dwelling parrots did not show dramatic increases in flock size in the evening, reflecting the lack of communal and multispecies roosting observed in other parrots. Generally, the large- and mid-sized species of parrots were associated with high-ground forest, whereas smaller species favored transitional forest. Because daily ranging patterns for these parrots potentially include all habitats, these patterns of habitat use suggest selection for subtle differences among forest types. As expected, smaller species were less detectable at a distance than large species. Comparisons of size and detectability indicate that macaws can be reliably counted to a distance of 300 m, but 100 m may be more appropriate for the smaller and low-flying genera. In sum, we found that observing parrots from the canopy is a useful method for quantifying parrot activities in a closed-canopy system, and that these forest-dwelling parrots are markedly less social than their counterparts on islands and in more open habitats. Patterns of flight behavior, habitat preferences, and the body size to flock size relationship invite further studies on the roles of predation and resource availability in the structuring of parrot communities.