The bald eagle is more often encountered by Americans on dollar bills and postage stamps than in its natural habitat. But several Eastern states are taking steps to keep eagles from becoming mere patriotic symbols.
New York State is in the vanguard of attempts to bring back the bald eagle, having imported more eagles in efforts to reestablish breeding populations than all other states combined. But a top state wildlife official there has warned that New York is still too polluted to sustain a significant number of the predators.
Later this summer, Peter Nye, director of New York's endangered species program, will travel to the forests of Southeast Alaska to collect 22 recently-hatched bald eagles.
This will be the sixth straight summer Mr. Nye has come for the baby birds. He has taken 130 wild Alaskan eagles home, where the birds have been reared in captivity and released when they were believed to have a chance to survive on their own.
Nye and other New York wildlife officials hope to reestablish breeding populations of bald eagles in portions of the eagles' former range that had been rendered uninhabitable, largely because of chemical pollution.
Conditions have improved in recent years, but state wildlife pathologist Ward Stone has warned that New York's environment is still too polluted to sustain a significant number of the predators.
``The New York environment is a mess'' says Mr. Stone. Acid rain, lingering concentrations of DDT, and a host of toxic chemicals associated with agricultural and industrial development threaten to kill eagles outright, interfere with their reproduction, and diminish their food sources, he explains.
Continued losses of suitable forest habitats and illegal shooting by hunters pose additional threats, Stone said. ``Official statements that the future looks bright for people to again enjoy the splendor of bald eagles as they soar against the powder blue New York sky are based on simplistic interpretations of the scientific data,'' he contends.
New York has imported 150 bald eagles in the past decade, including the 130 from Alaska. Officials in both states predict the eagle restoration program will permit millions of Americans to observe the majestic birds. Once found throughout North America, the bald eagle today is classified as an endangered species in 43 states. Only in Alaska is the bird not threatened by extinction.
Last month three eaglets were hatched by parents that were the first eagles to breed in the wild after being reared in captivity. ``We expect that our eagle population will continue its slow but steady upward climb,'' New York Environmental Conservation Commissioner Henry G. Williams said.
The first of the Alaskan eagles that were relocated to New York begin reaching sexual maturity this year. The extent of their breeding success, say the wildlife specialists, should indicate the readiness of the state's environment to support a substantial bald eagle population.
Bald eagles, which feed on fish and smaller birds, became scarce in much of North America for several reasons, the main one being the use of pesticides. After it was found that DDT was linked to the thinning of the eggshells of predatory birds, New York banned the pesticide in 1970. Two years later DDT was banned nationwide. DDT becomes concentrated in animals at the top of the food chain.
None of the other toxins in New York's environment are causing reproductive failures, Nye points out. Nevertheless, he and others in the state's environmental conservation department have dramatically lowered (from 40 down to 10) their estimate of the number of breeding pairs of eagles that can be established in New York by the early 1990s.
Department officials also state they have ``reevaluated [their] objectives'' and decided to ask permission to continue to take eagles from Alaska for at least two or three more years.
Nye had intended to quit rearing Alaska eagles last year, and Stone says continuation of the program is a sign that the birds may not be taking to their new environment as had been hoped. He says that only 6.4 percent of the eagles to reach sexual maturity in New York after being relocated from elsewhere have attempted breeding.
``I'm not opposed to trying to reintroduce eagles. I am opposed to the simplistic statements that somehow the environment has gotten better,'' he said.
Alaska officials expect only about 20 percent of the eagles relocated to New York will survive to breeding age, usually the fifth year of a bird's life, said Michael Jacobson, eagle specialist for the US Fish and Wildlife Service in Juneau.
Mortality among young eagles is always high, especially in their first year, said Mr. Jacobson. As many as 50 percent in the wild normally die of starvation or because of harsh weather.
Alaska has some 20,000 breeding-age bald eagles, about half of which live in the southeastern part of the state, according to Jacobson. He says the state ``can afford to give away another 30 birds this year without an apparent impact on the state's eagle population.''
After Nye collects 22 eagles for New York this summer, that leaves eight. Tennessee wildlife officials recently inquired about obtaining them.