The bald and the beautiful

Soap opera of regal eagles' life-or-death struggle nears happy conclusion

Dick Foster, Rocky Mountain News

Published February 24, 2007 at midnight

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Like the robin, another American bird seems to be on the verge of extinction. This is the national symbol, the eagle. It's populations have dwindled alarmingly within the past decade. The facts suggest that something is at work in the eagle's environment which has virtually destroyed its ability to reproduce. What this may be is not yet definitely known, but there is some evidence that insecticides are responsible.

Rachel Carson, Silent Spring

The bald eagle has symbolized the United States of America for 225 years, but only this year has it also come to represent the biggest success story in the modern environmental movement - saving a species that faced extinction in the very land that it symbolizes.

For decades before Rachel Carson's seminal 1962 book, the bald eagles' numbers had been dropping dramatically throughout the United States.

Hunters, sportsmen and American Indians sought the bird as a trophy and for ceremonies, while farmers and ranchers killed them, thinking they were a livestock predator such as the golden eagle.

The bald eagles' survival was not threatened in Alaska and Canada. But its numbers plunged in the lower 48 states from about 100,000 in 1782, when it was declared the national symbol, to 417 nesting pairs in 1962, when Carson's book warned that the pesticide DDT could deliver the eagles' coup de grace.

Congress passed the Bald Eagle Protection Act in 1940 to outlaw shootings and protect nesting areas, but it did not ban DDT until 1972 and did not pass the Endangered Species Act until 1973.

Now, 35 years later, those last few hundred nesting pairs of bald eagles have grown to an estimated 9,700 pairs nationwide, and in June, a federal judge will hold a hearing to consider delisting the eagle as an endangered species, said U.S. Fish and Wildlife Service recovery officer Seth Willey.

"We're very excited about this. We've worked very hard for a long time to recover eagles and to defend the Endangered Species Act, and this is proof positive that the act works," said Stephen Torbit of the National Wildlife Federation.

"We now have eagles where we haven't had them in 30 or 40 years," he said.

Including a growing population in Colorado.

Just passing through

For generations, hundreds of eagles migrated south to Colorado for the winter, but few stayed to nest in the spring.

"The thing that's really thrilling is that we've now got probably 50 to 60 nesting pairs in Colorado," said Jerry Craig, the Colorado Division of Wildlife's raptor specialist for 32 years before he retired in 2004.

"Now we've got an animal we can work with. The Division of Wildlife can take a proactive effort in assuring the birds around here are protected," Craig said.

The Endangered Species Act of 1973 established "critical habitat areas" for the bald eagle across the country and placed restrictions on property development in their habitat.

A federal judge's decision on delisting the bald eagle was originally scheduled for Feb. 16, in response to a 2005 lawsuit by a Minnesota developer and the Pacific Legal Foundation to remove the bird from the list, permitting development in eagle habitat.

The judge delayed his decision until June 29 after the U.S. Fish and Wildlife Service asked for more time to revise language in the Bald and Golden Eagle Protection Act, which will continue to prohibit killing or harassing bald eagles, disturbing nests, or possessing eggs, nests or anatomical parts.

Torbit worries that changing the act's language could soften federal protections for the eagle.

"This is kind of a dark cloud on the horizon," Torbit said. "The anti-wildlife folks want to change the language. There's a whole bunch of folks who don't want eagles to get in the way of any plans that they have, so there are attempts to weaken the 'disturb, harm and harass' components of that act."

State and federal wildlife officers are convinced that the law will remain strongly protective of eagles and their habitats.

"There are very high levels of protection," Willey said.

A shared elation

The decades-long effort to save the bird was widespread, across conservation groups, government agencies and the public at large.

Government wildlife officials shared Torbit's elation as they watched the eagle population recover.

"I would say this is one of the greatest accomplishments of the (Endangered Species) act," Willey said.

Colorado has always been a more peripheral habitat than a major nesting home for the bald eagle.

That's because the bald eagle is primarily a fisherman, plucking its dinner out of large bodies of open water such as lakes, marshes, coastlines and rivers that are more plentiful in other states.

Bird-watchers recorded only three nestings in Colorado from the 1890s into the 1940s, and there were probably a scattered handful of unrecorded ones, Craig said.

"We never had a big nesting population that they had in the Great Lakes and some of the northern states - Idaho, Montana, Seattle and elsewhere," Craig said.

Large numbers of eagles from farther north migrated to Colorado's San Luis Valley wetlands and the South Platte River Valley in the winter months, but returned north every spring to build their nests and raise their young.

"As a wildlife manager, they're kind of out of your hands. About all you can do is protect the habitat and protect the eagles when they're here. There's nothing you can do to enhance the population to increase the number of birds," Craig said.

Population spreads

But the Endangered Species Act was working, and as the eagles multiplied throughout the years, they began to spread.

"We started picking up a few nesting birds in northwest Colorado," Craig said.

New mating pairs were found at Standley Lake in Westminster, Barr Lake in Brighton, at the Rocky Mountain Arsenal, and along the South Platte River in northeastern Colorado, he said.

During the 1980s, some eagles adapted their eating habits to available Colorado cuisine - prairie dogs, rabbits and other land dwellers, along with the occasional trout, Craig said.

"As a result, the food source was there and they began to nest," Craig said.

"What's kind of neat is that, if these patterns continue, I think we're going to see nesting bald eagles here in Colorado for generations to come."

Fast facts on the bald eagle

• Color: Light gray at birth, dark brown when they leave nest after 12 weeks. Distinctive white head, neck and tail feathers don't appear until fourth or fifth year.

• Size: One of the largest birds in North America. Range from 29 inches to 42 inches in length, from 7 to 15 pounds, with a wingspan of 6 to 8 feet. Females larger than males.

• Life span: Up to 40 years in the wild, longer in captivity.

• Habitat: Near large bodies of open water, including lakes, marshes, seacoasts and rivers, where they can find their primary food, fish.

• Food: Mostly fish, but also ducks and small animals such as muskrats, rabbits and, in Colorado, prairie dogs. Occasionally will feed on dead animals.

• Flight: Can soar at 10,000 feet or higher for hours on wind currents. Can fly up to 44 mph, reaching speeds of 75 to 100 miles per hour when they dive to grab prey.

• Power and weight: Long, sharp talons can exert 1,000 pounds of pressure per square inch on prey. Can lift and carry about half its weight.

• Mating and breeding: Monogamous, the pairs mate for life and build large nests called eyries atop tall trees. Female lays one to three eggs each spring, which hatch after about 35 days. Both parents raise the eaglets until they are able to fly at about 12 weeks.Source: American Eagle Foundation

fosterd@RockyMountainNews.com or 719-633-4442

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