Birds with long, pointed wings such as falcons disperse the farthest when searching for food or migrating. However, the distance travelled also depends on body size; large condors migrate further than small finches or hummingbirds.

In a study reported in 2010, Orchan and his colleagues measured the wing dimensions of more than 300 European bird species across 53 families and analysed a database on movements during winter. They recorded whether birds were non-migrant, partial migrants or migrants, as well as how far the species migrated based on bird-ringing recoveries (see p8-9). The analyses reveal strong associations between flight performances and wing lengths and aspect ratios for long-distance avian migrant species.