Spring Hawk Migration in Eastern Mexico
Abstract
Hawk migration was witnessed along the eastern coast of Mexico for 23 days from 6 April to 6 May 1978 north of Veracruz. More than 262,000 hawks of 17 species were recorded, mainly Buteo platypterus (77%), Buteo swainsoni (6.4%), Cathartes aura (9.8%), and Ictinia misisippiensis (4.7%). A large proportion of the migrants may have passed in March and early April and a few after 6 May. Daily numbers of most species quickly decreased after 27 April. The importance of this flyway was evident from the 13,600 Pelecanus erythrorhinchos counted and from the several million other migrant birds seen.
Some behavioral features of migrants are described. The need for further survey work is emphasized.