Bald EagleWinter presents a host of changes and challenges for the bald eagle. (Photo David A. Murray)

It was a typical winter day in the northern hemisphere. Snow covered the ground and single digit temperatures maintained a hold on everything in its path. Plants and wildlife alike have no place to escape the season that challenges survival. Not for days but for months, the unrelenting weather separates the strong from the weak. Those that face the challenge and win, earn the right to survive and face the challenge again next winter.

Surrounding us, leafless trees creak in the cold wind and many animals seem to disappear as they hunker down to avoid the harsh weather. Our avian friends dart quickly from cover to the backyard feeders to grab a sunflower seed to restore lost protein.

However, what about one of the largest bird species, the bald eagle. How does a bird that survives almost exclusively on fish survive now that fresh water ponds, lakes, and streams are frozen?

The bald eagle is best known for its distinguishing position as our nation's symbol of freedom. This honor was bestowed on the bird when it was officially recognized and adopted as a national emblem of the United States on June 20, 1782.

Populations of bald eagles are scattered throughout North America, with the largest populations established in Canada and along the eastern and western United States coastlines and Alaska. Their range also extends into the interior states but in smaller populations.

As previously mentioned, the bald eagle's preferred food source is fish. Eagles are designed to catch fish using their very large, strong, feet and extremely sharp talons. Unlike other fish eaters, like their close relatives the osprey, bald eagles do not submerse themselves in the water, but instead grab their prey from the surface using their keen eyesight and deadly talons. Although their large, yellow, hooked bill is capable of snatching a meal, it is used solely for tearing apart the flesh of its prey.

Winter presents a host of changes and challenges for the bald eagle. As ice seals fresh water food sources, eagles seek out alternatives for survival. The problem is compounded in that along with fewer food sources is the need to expend precious energy flying around to locate new sources. Some eagles travel as much as twelve miles from their home territories to find food and, although they are a large bird, they are unable to carry more than three or four pounds of food in flight.

Many bald eagles will temporarily congregate in small colonies to roost at night. This then becomes a communal effort to locate food and eagles will follow one another from the night roost to a food source discovered by one of its colony members.

Fish are obviously hard to come by during winter, and bald eagles will often gather along the coastlines or sections of rapidly moving rivers that offer open water.

Carrion is also plentiful during winter, as the sick and weak succumb to the winter survival challenge. Dead critters such as moose, deer, elk, and caribou all provide large supplies of meat, although, competition is fierce during the winter and carrion does not last long. Predators such as wolves, bears, fox, bobcats, mountain lions, coyotes, lynx, and many others rely on this same winter food source. The bald eagle has a difficult time competing against many of these formidable predators and very often must wait for the scraps that remain after the large predators have had their fill.

Bald eagles are protected as an endangered species by the Federal Endangered Species Act and deserve a heightened awareness during winter. An increased viewing or photographing distance should accompany a heightened awareness.

When viewing bald eagles during winter, especially at a food source, you should use adequate binoculars to keep a safe distance. If your goal is to photograph eagles at a food source, winter is not the time for point-and-shoot equipment. A 500mm lens is the minimum focal length for maintaining a non-intrusive distance. Also, using a lens any shorter is not going to be effective, because the bird will fly away before you get close enough for a worthwhile picture. This creates unnecessary stress on the birds, and no picture is worth jeopardizing the welfare of eagles or, for that matter, any wildlife.

Many of the possible food source locations during winter, both along the coastlines and other large waterways, now pose new problems and threats as development and urban sprawl rapidly diminish the areas these shy and reclusive birds can fish. If you become aware of bald eagles in any of these types of locations that have adapted to fishing, it is imperative that they be allowed to fish undisturbed. If disturbed or feeling threatened, they often will not return to that food source location. The same holds true for carrion locations, view the eagles from a safe distance.

Remember, some of those bald eagles may have flown over ten miles and expended a huge amount of energy to eat, and that one meal may make the difference between winter survival and death.

Good shooting!

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