Aerial Dispersal of Insects Between and to Islands in the Galápagos Archipelago, Ecuador

Resumen

Active or passive movement of insects through the air is probably their most common means of dispersal to oceanic islands. Use of aerial nets suspended on boats documents the presence of insects in the air between the islands of the Galápagos Archipelago during the 1991–1992 El Niño climatic event. At least 50 species of terrestrial arthropods in nine orders were captured. The most abundant families were Aphididae, Aleyrodidae and Psyllidae (Homoptera), Encyrtidae and Formicidae (Hymenoptera), and Sciaridae and Ceratopogonidae (Diptera). The moist conditions and winds during a strong El Niño probably create the most favorable circumstances for aerial movement of insects between islands of the Galápagos and for movement from the tropical American mainland to the Archipelago.