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In fact, millions drown at sea during migration.īirds will group during their migration, even when they are normally solitary during other times. If the birds happen to be flying over a body of water, like the Gulf of Mexico, this will drown many. It breeds in the northern most regions of Asia, Europe, and North America, then for winter, will head to the Antarctic ice pack 11,000 miles away.ĭuring flight, sudden changes in weather that cause fog, heavy rains or winds will often stop migrating birds in their path. But perhaps most impressive is the Arctic Tern ( Sterna paradisaea). The American Golden-Plover ( Pluvialis dominica) will assemble in southeastern Canada, then begins its nonstop flight over the Atlantic Ocean to Brazil, traveling about 2400 miles at the incredible speed of 60 MPH. For some examples, the Ruby-throated ( Archilochus colubris) Hummingbird flies about 600 miles across the Gulf of Mexico nonstop. There are also the marathon lengths some birds must go. Migration can be particularly dangerous for birds, as it involves challenging journeys that can be negatively affected by weather, predators, and human interference. There are several primary routes birds typically use, and one is right over Texas: the Central Flyway. Some birds make long distances, sometimes crossing oceans, while others may go down a mountain just a few miles. Migratory birds follow specific routes defined by geography, altitude, and they can alter their course depending on weather conditions they meet during their journeys.

They also weigh less and have longer and more pointed wings.įrom " Migration and the Migratory Birds of Texas: Who They Are and Where They Are Going" Texas Parks and Wildlife

They can build fat stores as energy sources. Migratory birds have some adaptations that make them different from birds that do not migrate. For example, many nesting species migrate from Canada to the Gulf Coast States for winter.Īs with many things about bird migration, the mechanisms that trigger it are not completely understood, but include temperature changes, alteration in food supply and day length, as well as genetic predisposition. Areas with more severe climate see a larger percentage of bird migration. Spring migration is shorter, about four weeks from mid-April to mid-May.

Fall migration spans a longer time range, late August into mid-November. Milder regions provide more food options, but also more daylight hours to find the food they and their nestlings need. In the Northern Hemisphere when the weather changes, birds move north in the spring and south for the winter. Birds need abundant food supplies because of their high metabolic rate. The reasons why and where they go are largely about nesting resources and food. Why do birds migrate? First, not all birds do. Through the course of the season, millions of birds will pass through the Lone Star State on their way to warmer southern climates, or some will stay here for a while. Of Texas’ 615 documented species of birds, about half will migrate. It’s also a time of migration for some birds. The weather is cooling and the days are getting shorter.