Avifaunal relationships between the Neotropical and Ethiopian regions

Abstract

Excluding Holarctic migrants, there are 14 species of land and freshwater birds common to the Neotropical and Ethiopian regions, all non-passerines and all but four are species that have invaded these regions from the north. Of the remaining four, the Cattle Egret (Bubulcus ibis) certainly, and the White-faced (Dendrocygna viduata) and Whistling Ducks (D. bicolor) probably, invaded South America from Africa. The evidence in respect to the Pochard (Netta erythrophthalma) is inconclusive. Despite the strong and steady westerly winds in the South Atlantic, only one South American bird, the American Purple Gallinule (Porphyrio martinicus), has been recorded as a stray from Africa. Among seabirds, the Grey-headed Gull (Larus cirrocephalus) probably invaded South America from Africa, but several alternative explanations are possible for the distribution of the Southern Black-backed Gull (Larus dominicanus). The penguin genus Spheniscus is almost certainly of South American origin. There are interesting parallels between the guano-producing seabirds of the west coasts of South America and Africa: in each region, a gannet (Sula sp.) and a cormorant (Phalacrocorax sp.) are the most important species, but they appear to have evolved in situ from different ancestral stocks.