Avian Extinctions in an Isolated Tropical Wet-Forest Preserve, Ecuador

Resumen

Abstract The avifauna of a small forest island in lowland Ecuador was surveyed to detect recent extinctions. The 87-ha national forest, at Rio Palenque, has had serious declines in bird species numbers, even within the relatively short period of 1973-78. Among the 170 species of forest-dwelling birds, I found no recent records for 19 species, 25 had been last noted in 1975, and 15 presently have precariously low populations. Attributes of the species that had local extinctions included, in order of importance, large body size (predatory habits), general rarity (specialization), or declining populations throughout their range. Illegal hunting was related to the loss of two species at the preserve. The importance of large refuges is reaffirmed by this study.