This is the first in a series of articles I will be writing in this newspaper about various nature-related topics that I hope will be of interest to that little bit in all of us that is curious about the "wild side" of our natural surroundings in East Central Illinois. We are now enjoying beautiful autumn leaves–a phenomenon that occurs in the fall which never ceases to fascinate me.
Bird Migration: What is it?
An amazingly diverse group of animals, birds have evolved to adapt to a great variety of habitats and modes of life. They occupy forests, deserts, fields, shorelines, and nearly every habitat in between. Species select environments according to their need for food, water, space and nesting locations and materials. Generally, they match or "fit" into a particular environment based on those needs. While they are adapted to a particular habitat, they must also be able to tolerate the same changes that the environment endures – the change of seasons, long-term changes, and sudden erratic occurrences. More than any other group of animals, birds deal with seasonal changes in the environment by an evolutionary adaptation known as migration. This extraordinary feat is a yearly flight cycle that is closely timed to the patterns of seasonal changes that occur in a region. While it is a familiar annual occurrence to those of us who observe our natural surroundings, it remains a puzzling mystery to many.
Why do birds migrate?
The purpose of migration is to escape unfavorable conditions such as lack of food or cold winter weather and take advantage of beneficial conditions in other climates. Many birds will breed and raise young in northern areas during spring and summer, then fly south to warmer climates for fall and winter. How far they travel is a relative thing. In autumn, birds will migrate as far south as needed to find food and a secure habitat for the winter. For the Ruby-throated Hummingbird, that may mean it must fly from Southern Canada in the summer all the way to South America for the winter months, then back again in Spring. For some bird species that nest in Alaska and the Northwest areas of Canada, migrating only as far south as Minnesota may be enough to secure needed food and shelter.
What is a "flyway"?
Some migratory birds follow familiar territories and flyways (migratory "highways"). Illinois has the advantage of being situated in the middle of the Mississippi Flyway, a route used by many species of ducks and geese, as well as smaller species such as our summer resident songbirds as they travel south to the Gulf areas, Mexico and South America.
For some birds, migration can be a long and wearying undertaking. It remains, however, a wonderful and fascinating survival strategy that many species need simply to ensure the success of their offspring and thus the preservation of their species. The many refuges along the Mississippi River provide important feeding and resting areas for migrant birds. People find in these places great opportunities for watching or photographing both resident and migratory species. One need not travel so far, however, to observe this seasonal marvel – a step outside on a crisp autumn day may reward your eyes and ears with the distinct vision of a flying "V" formation overhead and the raucous honking of a flock of Canada geese as they slowly fade into the distance. To truly appreciate this annual jewel of nature, just look to the southern sky.