Reverse Migration, Overshoots, and the Concentrating Effect of Oceanic Islands on Migrating Birds
Oceanic islands are well known for the occurrence of extralimital vagrants, and Bermuda may get more than most, as it is located between the two American continents. More vagrants occur during fall migration because cold fronts coming off North America help push migrating birds southeast toward Bermuda. Fewer occur in the spring, both because the winds most favorable to northward migration are southeasterly (off the Bermuda High) and tend to push birds onto the continent, and because migration patterns/pathways are different between spring and fall. Lying almost equidistant (>800 km) from Nova Scotia (to the north), Cape Hatteras (to the west), and the West Indies (to the south), Bermuda is an ideal place to study bird migration both to and over small oceanic islands. The migrants that land on Bermuda can be separated into four basic categories, which are here subsequently defined and illustrated with examples.
David Wingate was born in Bermuda in 1935 and received a bachelor’s degree from Cornell University in 1957. As Government Conservation Officer, he managed the successful Cahow (Bermuda Petrel) conservation program 1958–2000. David moved to Nonsuch Island in 1962 and has since worked to restore it as a “living museum” of precolonial Bermuda.
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