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Bald Eagles

Ohio had the first long-term observation of bald eagles nesting in 1959. It was also one of the first states to notice and document the consistent decline of the bald eagle; at that time there were 15 nesting pairs. This number steadily declined over two decades to only four pairs. The Ohio Division of Wildlife set a recovery goal of 20 nesting pairs by 2000. The number reached 29 nests in 1995. The folks at the Division of Wildlife created a four-pronged approach to eagle research and management: public education about the needs of wild eagles; rehabilitation of injured birds; nest site monitoring; and, fostering captive bred birds into the wild. The result, ahead of schedule, is more bald eagles soaring in Ohio 's sky.

The only solutions that are lasting ones involve cooperation. Individuals, organizations, neighbors, states, and even countries will have to step over boundaries to keep what is important. The Cincinnati Zoo and the Ohio Division of Wildlife are good examples of that kind of cooperation. The goal was to increase the number of eagles in the wild. The Zoo has had success at breeding eagles and the state's Division of Wildlife has successfully released eaglets in the wild to try their wings at flying free.

The symbol of the Eagle

Eagles are admired and has been the American national symbol since 1782. But, most importantly, bald eagles are today a symbol of hope for other endangered species. Since bald eagles have made such a strong recovery, they illustrate the hope that they can save endangered species.

In 1940 the U.S. Congress enacted the Bald Eagle Protection Act safe guarding the bald eagle. This made it illegal to kill, harass, possess (without a permit), or sell bald eagles. This was followed and expanded upon beginning in 1973 when the Endangered Species Act was made law which extended the principles of protection in the Bald Eagle Law to other endangered species.

It's an All-American Bird. The bald eagle is the only eagle that is unique to North America . Eaglets remain in the nest for the first 11 to 12 weeks... and for two or more months they frequently return to beg for food from their parents. There is no species in this country that better signifies a hopeful sign for the environment than the bald eagle. The bad news is they have suffered from the deadly combination of habitat loss and the over use of dangerous chemical pesticides throughout most of the second half of this century. The good news is that throughout its range the bald eagle is staging a dramatic comeback. DDT and other dangerous hydrocarbon-based pesticides were heralded as miracle chemicals for insect eradication at the end of the Second World War. They now realize there are no such miracles.

By the 1960s, led by the remarkable efforts of Rachel Carson as chronicled in her book Silent Spring, it was proven that these poisons don't just kill the insects they target, but in fact impact the entire food web. Through a process called biological magnification, these dangerous chemicals build up in the fatty tissue of animals that ingest them. As a result, over time, the concentration of poison increases as it moves up the food chain from aquatic invertebrates eaten by small fish and then to larger fish. This occurs even in the animals that eat the large fish, such as brown pelicans, osprey and bald eagles, all of whose numbers dropped dramatically in the 1950s and 1960s. As DDT built up in their systems, it resulted in the death of adult birds as well as eggshell thinning which reduced the number of eagle eggs that actually hatched.

Fortunately, the use and abuse of these chemicals was stopped in this country, and these predators at the top of the food chain are beginning to thrive once again. The most significant part of the eagle's story has to do with people. Scientists have since shown that DDT is also stored in human fat cells and at high enough concentrations is carcinogenic. So, by cleaning up the environment and making it safe for eagles, they are actually making it safe for themselves.

Through a process called biological magnification these dangerous chemicals build up in the animals that ingest them. Wetlands are magical places where land and water mix. They span the world and support an amazing variety of creatures and complex ecological systems. It is that combination of water and land that makes these areas such rich, interdependent habitats. Wetlands are essential as a food source and for breeding a myriad of species. In a world dependent upon water for all life, wetlands are the intricate launching pads for the wildlife all around us.

With bald eagles wetlands are the whole point. Because the eagle's primary prey source is fish, its territory will always include water as a main component. Just as eagles prefer wetland habitats, they people seem to have the same preference. As a result, the pressure on wetlands across the country has been tremendous. Across the United States less than half of their original wetlands exist today. Ohio has lost 90% of wetland areas. Both agricultural and developmental demands have placed a heavy burden on wild, untouched wetland places...the very places eagles and other species need to thrive.

Now as they realize that they are running out of space for these magnificent raptors, they are beginning to understand the importance of balancing the needs of people and wildlife. It is the increased concern and understanding about the needs of wild creatures combined with strong and balanced legislation that will keep some wild places, their natural savings account, around for future generations. This takes understanding and planning and a thought toward the future, but what Rachel Carson started with such clarity and inspiration they can surely complete and insure.

Today the bald eagle may be the most protected bird in the world, but that has not always been the case. Specific laws, including the Bald Eagle Protection Act (1940) and the Endangered Species Act (1973), have combined to insure that the bald eagle does not go the way of the passenger pigeon.

Now the bald eagle is a true American success story. Its population in the lower 48 states increased sufficiently from 450 nesting pairs in 1960 to 4,000 in 1995; this once endangered bird has now been upgraded to a threatened status over most of its range. In Ohio , as everywhere, the comeback of the bald eagle can be attributed to habitat preservation, a reduction in the use of pesticides such as DDT, public education about the needs of eagles in their state, nest site monitoring, and the release of captive bred birds back into the wild. The Cincinnati Zoo has played a role in this plan by releasing young eaglets to fly free in cooperation with the US Fish and Wildlife Service and the Ohio Division of Wildlife. One of the results of this partnership is that Ohio 's eagles have steadily grown from a low of four nests in 1975 to over 30 nests in 1997.

The bald eagle's recovery has been impressive; however, as with all environmental issues, there are no final chapters, only future challenges. Their current challenge is this: Can they keep this species in its strengthening state...or do they backslide? The future of the bald eagle depends on how one species - Homo sapiens - which means "wise man" in Latin - treats the rest of life on Earth. How will they balance all these needs? What will their priorities be?

The problem is that the more wild places develop, the less there is for even the small birds. Can we really run out of "space" for creatures that are so small? Can we leave room? It takes planning, understanding , and valuing to keep the necessary parts of a healthy wild system to support birds and all that they need to live.

What is a bald eagle?

Bald eagles are large, beautiful birds of prey, with wingspans of up to 7 1/2 feet across. Despite their name, bald eagles are not really bald. It is the snowy-white feathers on their heads that give them that appearance. This white plumage does not develop until the bird's fifth year. It is a sign of a fully mature bird and may help to attract mates. During their first few years, young eagles or sub-adults are brown all over with a mottling of white feathers under their wings. At this age they resemble the other eagle species in this country, the golden eagle.

The hooked beak and sharp talons, as on all raptors, are used for catching, killing and eating prey. Bald eagles are opportunistic, which means they adapt their feeding habits to the available food supply. But they feed mostly on fish, which they scoop from the surface of the water and carry off to eat on land or while perched in a tree. They will also catch small mammals, birds, and reptiles or feed on carrion.

Together a male and female eagle build a nest high in a tree near open water, generally 50 to 100 feet off the ground. The eagles' stick nests are the biggest in the world, and some are used for many years. Nests 12 feet high, nine feet across, and weighing more than one ton have been found.

Adult eagles can weigh between 8 and 12 pounds. Like most birds of prey, the females are larger than the males, outweighing them by as much as 30 percent. Scientists don't know for sure why there is such a difference in the size of males and females, but they believe that birds of prey, like eagles, are a double-income family, allowing the stronger female to catch larger prey, while the smaller male can catch quicker prey. In addition, the female bares the responsibility of laying the eggs.

All over the world people have long revered eagles. They are magnificent flyers and strong, powerful birds. Throughout time, from the ancient Greeks and Native American cultures to current flags and national symbols all over the world, eagles have been used as representations of strength and freedom.

In total there are 64 species of eagles. All are diurnal predators which means they hunt during the day. But eagles come in many different sizes. The biggest is the female Steller's sea eagle that can weigh over 19 pounds and has an eight-foot wingspan. The little eagle of Australia has been given this name because it is the smallest of all eagles. It weighs a little more than one pound and is just three feet from wingtip to wingtip.

In many parts of the world eagles are the ultimate symbol of wilderness. This is not just in the poetic sense of strength and freedom, but also in terms of the ecology of a wild area. A good example is the harpy eagle. Field biologists who work in South American forests have found this eagle to be the very best indicator for truly wild places. Being at the top of the food chain, harpy eagles require large tracts of undisturbed habitat with few people nearby.