It seems that just as we're beginning to enjoy the colors of autumn, those warm hues are replaced by the dismal browns of leaves carpeting our yards. As temperatures drop, mammals begin to hunker down in warm dens and many birds have left the Chesapeake to spend the season basking in the southern climates of Caribbean, Mexico and Central and South America.

Many birds, though, do not fly south for the winter. Remaining in neighborhoods all across the Chesapeake Bay watershed, these hardy residents bring a splash of color and hours of entertainment to backyards everywhere.

How do they do it? Birds, like mammals, are warm-blooded animals and must maintain a constant body temperature as the temperature around them changes. To do this, they spend much of their time feeding so they can generate enough heat. It's a vicious cycle though; they must eat to keep warm so they can gather more food.

During the warmer months, insects and other invertebrates provide much of the needed nutrition. Birds that can switch from an insect diet to a seed diet can stay put throughout the winter.

For birds, finding food and water during the coldest months of the year can be a formidable task. Feeding birds and bird watching are popular hobbies. It's easy to do and one can start at any time.

A feeding area should provide birds with easy access to food while also providing protective cover from predators. Set up feeding stations near shrubs, trees, brush piles or fences. Evergreen trees and shrubs, like pines, hollies and cedars, provide excellent cover and protection, as well as a natural source of food.

Different styles of bird feeders and different seed mixtures, one can attract specific bird species to a yard. Mixed birdseed on a simple tray or a platform feeder mounted above the ground attracts sparrows, dark-eyed juncos, blue jays, starlings and grackles.

A tube feeder filled with sunflower seed is sure to delight some of the smaller birds like the American goldfinch, black-capped chickadee, Carolina chickadee and tufted titmouse. Thistle seed in a tube feeder is a favorite of goldfinches, purple finches, house finches, chickadees and a variety of sparrows.

Cage-style suet feeders hold square cakes of rendered suet, which is processed to kill bacteria. Suet attracts chickadees, nuthatches, brown creepers, woodpeckers, wrens and cardinals. Suet should be hung high enough so that dogs, cats and other animals cannot reach it.

Often, squirrels visit bird feeders and, in many cases, can become a nuisance by consuming the majority of the seed. Squirrels may also damage feeders by chewing through plastic and wooden parts. One way to curtail this problem is to erect squirrel guards, metal cones placed above hanging feeders and below feeders mounted on poles. Squirrels simply slip off the guards before they can reach the seed.

Many people solve their squirrel problem by creating a squirrel feeding station away from bird feeding areas. Uncooked corn on the cob is a favorite of squirrels and can be used to lure squirrels away from a bird feeder.

Even without commercial feeders, one can lure birds into a yard. Mixed seed and sunflower seed spread on the ground will bring sparrows, cardinals, mourning doves and common flickers.

Peanut butter on pine cones and sweetgum balls rolled in a birdseed mixture and hung from trees will be popular with birds that hang while eating, including woodpeckers, nuthatches and chickadees. Dried fruit can also be hung and is a favorite of some of the larger bird species such as mockingbirds, woodpeckers, starlings, cedar waxwings, cardinals and blue jays.

Fall fruiting plants are great food sources for both migratory and resident birds. Dogwood trees, mountain ash and winterberries are some fall-fruiting plants. Of course, nut-

producing trees provide meals for a variety of birds like blue jays, woodpeckers and titmice that feed on broken nuts. These trees include oak, hickory, chestnut, butternut, walnut and hazel trees.

Winter-fruiting plants have fruits that remain long after they ripen in the fall. Many are not palatable until they freeze and thaw a few times. Examples of these include Virginia creeper, sumacs and American bittersweet.

We often forget that birds also require water. Cold temperatures may freeze available water sources, making them completely inaccessible to birds. Birdbaths or even a shallow pan or bowl filled with water will satisfy a bird's water requirements. Water sources must be kept ice-free for the birds to benefit. Like feeders, water sources should be placed off the ground and positioned near trees or bushes.

Once birds have become accustomed to feeding stations, they will continue to return for more food. Do not suddenly cut off the supply of food, especially during periods of severe weather.

Feeding birds is obviously beneficial to them, but people get a lot of enjoyment too. In fact, the 2006 National Survey of Fishing, Hunting and Wildlife Associated Recreation, conducted by the U.S. Fish and Wildlife Service, found that 55.5 million people reported feeding wild birds, making it the most popular wildlife-watching activity.

Attracting and feeding birds awakens a lifeless yard, porch or patio. The brief, gray days of autumn and winter brighten with the addition of song, color and activity. By providing for the needs of these active and delicate visitors, we bring the natural world a little closer to home.

For information, visit www.fws.gov/migratorybirds/pam phlet/pamplets.html.