Can Arizona’s desert-nesting bald eagle survive removal from the Endangered Species List?

During the winter of 1989, somewhere over the Verde River near Beasley Flats, a male bald eagle collided in mid-flight with a peregrine falcon. The collision caused a blood clot in the eagle's brain and killed him, leaving his partner and two five-week-old babies to fend for themselves. Without their father to bring food to the nest, the eaglets probably would have starved to death, except that James Driscoll, then a young intern with the Arizona Game and Fish Department’s Nestwatch program, had witnessed the freak accident.

“We’d get up at the break of dawn and throw fish out for the mother and then I’d go up and watch,” said Driscoll, who is now the AZG&F Raptor Management Coordinator. “It allowed her to stay near the nest. She didn’t have to go far to forage, and it helped fledge the two babies.”

Desert bald eagles, like all bald eagles in the United States, were then listed as “endangered” under the Endangered Species Act (ESA). Thanks to the Act and the funding it provided for programs like Nestwatch, biologist counted 43 breeding pairs of bald eagles in Arizona in 2006, the highest recorded since 1978. Good news like that for the bald eagle nationwide has conservationists across the country celebrating one of the greatest success stories since Congress established the ESA in 1973. In 1995 the US Fish & Wildlife Service downgraded the bald eagle from “endangered” to “threatened,” and now USF&WS wants to remove it from the list all together.

Colliding biologists

But in Arizona, that move is causing a collision of sorts between the federal government and the Center for Biological Diversity (CBD) in conjunction with the Maricopa Audubon Society (MAS). Both latter groups say that the desert-nesting bald eagle population is still far too fragile to be taken off the Endangered Species list. In 2004 the two organizations filed a petition to reclassify the desert-nesting bald eagle as an endangered Distinct Population Segment and designate critical habitat for it under the Endangered Species Act. In order to achieve Distinct Population status the population must prove to be discrete from other populations of the species, significant to the species as a whole and at risk of extinction.

USF&WS must respond to petitions within 90 days, and when they failed to do so, CBD and MAS filed a lawsuit in March of 2006. The following August, USF&WS found against of the petition; CBD and MAS subsequently filed a letter of intent to sue in November, declaring in the letter that they “will not allow the US Fish and Wildlife Service…to shove the Desert Eagle over the brink of extinction.”

“[The petition] did not meet our policy for finding that something is a Distinct Population Segment,” said Jeff Humphrey of the USF&WS. “It’s a three part test and we found that yes: the bird is discrete, but significant: no, and threatened with endangerment: no.”

USF&WS agreed with the petition that the desert-nesting population is discrete due to its unique geographical location, early breeding season, and isolation from other species. But the service did not agree that the population is biologically significant because, as Humphrey explained, even if the population in Arizona was lost, it wouldn’t significantly affect bald eagle populations as a whole. As for the petition’s evidence that the bird is at risk of extinction, USF&WS found that the increasing number of birds over the last 20 years is a sufficient indication that the population is not threatened with endangerment.

“We’re looking at whether, biologically and scientifically, the population is significant,” said Humphrey. “As a native and current resident of Arizona it is significant to me, as it is to many Arizonans. But under the federal Endangered Species Act it asks us to look at the biological significance, not the local and emotional or aesthetic significance.”

CBD and MAS, however, believe that without active management and habitat protection the current population of the desert-nesting eagle is threatened with endangerment.

“No other law defines habitat like the Endangered Species Act,” said Bob Witzeman of the Maricopa Audubon Society. “Once the bird is de-listed its habitat will no longer be protected.” The two organizations are highlighting Prescott’s proposed diversion of water from the Big Chino Aquifer, which feeds the Verde River, as an example of a future threat. The center believes that the diversion will harm at least six nests along the Verde River—in Perkinsville, Towers, Oak Creek, Beaver, Ladders, and Coldwater.

'Non-mandatory' protection

USF&WS, however, points to other federal bald eagle protections beyond the ESA, including the Bald and Golden Eagle Protection Act and the Migratory Bird Act, as sufficient, though neither of the Acts provides actual habitat protection. To make up for the lack of protection USF&WS is developing non-mandatory guidelines for recreation and development near bald eagle habitat. In Arizona, the service also plans to put more responsibility on the state Game and Fish Department.

“For years they’ve demonstrated that they’re energized and capable of fulfilling this role,” Humphrey said.

“Basically what it means is that we’re going to continue the same amount of management for the species post de-listing as we do right now,” Driscoll said of AZG&F. That management, according to Driscoll, will continue to include a comprehensive demography study, seasonal closures and the Nestwatch Program.

“With de-listing comes some loss of habitat measures, but it doesn’t mean that everybody can just go in and bulldoze around a bald eagle nest and put up houses,” he said.

Witzeman, however, remains skeptical. “It’s because of the Endangered Species Act that programs like Nestwatch get funding,” he said. “When species are taken off the list funds gradually dry up.”

Nestwatch still watching

But for now the Nestwatch program in Arizona is still working as diligently as it was in 1989. The male fledgling that survived the nest at Beasley Flats 15 years ago has moved up the Verde River to the Towers breeding area, where the Nestwatch program is still looking out for him. His nest, like that of his parents, is another example of their struggle for survival. First, the high level of contaminants in the female caused her eggs to fail two years in a row. The following year her eggs hatched, but then the nest really started to have trouble.

“We realized their nest was infested with Mexican chicken bugs,” Driscoll said. “They’re like bed bugs, and basically they suck blood out of the babies until they succumb to the heat and dehydration. We’ve lost six babies out of the nest over the past six years.”

Once again Nestwatch came to the rescue, this time spreading diatomaceous earth (microscopic dust made of seashell particles) all over the nest and the cliff. The dust killed the Mexican chicken bugs at first, and Nestwatch brought the babies up to about 10 weeks old before the bugs came back. They killed one baby. The one that survived has Nestwatch to thank.

(Chase is a freelance journalist living in Prescott.)

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