Migration

Migratory animals travel along the same general routes each year. Several common "flyways" are used by North American birds on their southward journey. The most commonly used path includes a 496-682 mi (800-1,100 m) flight across the Gulf of Mexico. In order to survive this arduous journey, birds must store extra energy in the form of fat. All along the migration route, but particularly before crossing a large expanse of water, birds will rest and eat, sometimes for days at a time. The recommencement of the journey will begin only when a certain amount of body fat is reached.

The requirement of stopover sites in addition to breeding and wintering sites makes migratory animals particularly susceptible to habitat loss, and thus many migrants are among our most endangered species.

Although most migrants travel at night, a few birds prefer daytime migrations. The pathways used by these birds tend to be less direct and slower than those of night migrants, primarily because of differences in feeding strategies. Night migrants can spend the day in one area, foraging for food and building up energy reserves for the night's non-stop flight. Daytime migrants must combine travel with foraging, and thus tend to keep to the shorelines, which are rich in insect life, capturing food during a slow but ever-southward journey.