Neotropical migrants are birds which breed in British Columbia during the summer months, and when winter arrives, they fly down to Central and South America, Mexico or the Caribbean Islands. Migratory birds are important to British Columbia, as they maintain a healthy biorhythm throughout the province, as well as the entire continent. There are about 200 species of neotropical migrants, the majority being songbirds. They also include shorebirds, some raptors, and waterfowl. The driving force behind migration is food availability. Birds need to utilize food sources when they are abundant, and when food becomes limited, their genetic instincts take over which drives them to migrate.

Birds have an internal clock that tells them when to migrate; environmental factors such as the slant of the sun, temperature and rainfall keep this clock in sync, kind of like how your clock at home uses batteries to keep in sync. Biologists have also found special glands in migrating birds that release hormones that make the birds grow restless; this is called migratory restlessness. Neotropical birds which migrate long distances, have their location they migrate to, hardwired into their brains; however, short distance migrants are shown the location they migrate to by older more experienced birds. Both short and long distance migrants essentially build mind maps as they migrate for future reference. Birds can determine which direction (north or south) they need to go by combining cues from landmarks on the earth’s surface, patterns of stars and position of the sun in the sky.

Related Link

• Smithsonian National Zoological Park