AUSTRAL BIRD MIGRANTS IN PARAGUAY

In the temperate latitudes of South America, populations of many speci es of austral bird migrants move northward from their breeding grounds to warmer latitudes during the austral winter. We identify 35 species of birds that presumably nest in Paraguay but are absent or rare duri ng the winter (northern austral migrants), and 45 species with populat ions that winter in Paraguay but breed in areas farther south (souther n austral migrants). We summarize the status of each species and justi fy its recognition as a long-distance migrant by providing extreme dat es of occurrence or other pertinent observations. New distributional r ecords and extreme migration dates are reported for many species. The austral migrant fauna is dominated by flycatchers (Tyrannidae), which account for 40% of the species. Most species of austral migrants are i nsectivorous.