Insects in birds’ nests from Argentina. Caracara plancus (Miller, 1777) and Milvago chimango (Vieillot, 1816) [Aves: Falconidae]

It is generally believed that nests of raptor birds (Accipitridae, Falconidae, Strigidae) are inhabited by a peculiar fauna of insects, mostly associated to prey remains. This faunal assemblage was studied in the Northern Hemisphere (Canada, Hungary, Korea, Japan, Norway, South Slovakia and United States). In the Southern Hemisphere, isolated mentions of hematophagous bugs from Venezuela, Colombia, Brazil (Reduviidae: Triatominae) and Argentina (Cimicidae), and one mention of fly larvae in Argentina (Santa Cruz) were made. For to known the insect fauna of raptor nests from Argentina, a total of 16 nests were sampled: 4 of Caracara plancus (Buenos Aires; Entre Ríos) and 12 of Milvago chimango (Salta; La Pampa; Buenos Aires). A total of 6274 insects were recovered from the nests of C. plancus, and only 984 from the nests of M. chimango. Except by only one species of Trogidae (Coleoptera) in one nest of C. plancus, all other insects are shared with nests of non raptor birds (Furnariidae, Mimidae, Psittacidae) in the same localities. Probably this was because all nests were inactive at the sampling data (except one of M. chimango with an incubating bird), and the prey remains present in the nests were old. Therefore, sampling of nests inmediately after the fledging period are needed.