Fly Like an Eagle

A wildlife biologist braves the rigors of small-plane flight to document the soaring prospects of Minnesota's eagles.

By Greg Breining

Flying a bald eagle survey requires a cast-iron stomach. Especially on a day like today, when, in the words of pilot Fred Petersen, the conditions are "sporty." The gusty wind whips the tiny Cessna 182 Skylane through the air like a kite. The plane finds stability only in the dizzying turns above the eagle nests. As Petersen, a conservation officer who flies for the Department of Natural Resources, pulls out of a steep bank and returns to level flight, the wind again kicks the plane across the sky.

Joan Galli, a DNR nongame wildlife specialist, has nothing like a cast-iron stomach. She remembers getting carsick in the family sedan on a straight, level road. Yet for nearly 20 years she has gamely climbed aboard a light plane to dipsy-doodle in a variety of weather, winter and summer, to tally Minnesota's eagles at established nests and to look for new nests.

She balances a topographic map and clipboard on her lap. Handwritten dots and codes show the locations of about two dozen nests along the Mississippi River from the Twin Cities to Lake Pepin. The river valley passes 300 feet below. In early April the river bottom is a simple palette of coffee-brown river, dead grass, and gray woods with a breath of lively green in the branches.

The crew's first assignment is RM 1, otherwise known as the Pig's Eye nest, located virtually at the end of a Holman Field runway on the Mississippi River backwater named for one of St. Paul's illustrious founders. "Those eagles must be deaf," Galli says. Petersen punches up the nest's coordinates on the GPS unit on the dash of the plane: 2.18 miles at a bearing of 142 degrees. The plane banks to the proper bearing and levels.

"Left or right?" Petersen asks.

"You need to go left a little bit so I can see. Left a little more."

Down below, the nest spins around as though sucked down the vortex of the whirling river bottoms.

"It looks empty," Galli says, jotting the fact in her notes. "I wonder where they went."

So off they fly to the next nest--DK 7, Dakota County number 7--on a small wooded island a mile below the Interstate 494 bridge.

"That one looks empty too," Galli says. "Definitely empty. That's bad news--two for two."

Were the eagles killed? Possibly. She knows also that if eagles fail to produce young one year, they build a new nest in the same territory, as if they blame the nest for their failure. Indeed, that might be what happened.

Petersen calls up the coordinates for the third nest, and the plane heads down the river. Bald eagles aren't the only large birds to nest in the flood plain. Hawks and waterfowl fly below. Great blue herons and great egrets gather in bottomland colonies. In contrast to the sturdy nests of bald eagles, which resemble overturned beaver lodges, the nests of herons are so flimsy as to be nearly transparent. From the plane they look like wisps of debris left in the branches by a 10,000-year flood.

Near Hastings, they locate DK 2. An eagle appears as two white spots--her head and tail--in a pit of sticks.

"Oh, yes," Galli says. The ominous trend is broken.

As Petersen pulls out of the turn, an immature bald eagle flies by, 100 feet away.

"Watch out for the bird," Galli calls out.

By now, as far as Galli is concerned, the buffeting of the wind is not the least bit sporty. As much as she enjoys the eagles, she has always dreaded these flights. Even the scopolamine patch she stuck behind her ear this morning has not quelled the sickening gyration of the map, river bottoms, and elastic horizon into a whirling montage. She begins to break into a clammy sweat and knows it is time.

"I don't see anything, and I think I'm going to be sick," she tells Petersen, and he sets the plane down at the Red Wing Municipal Airport, where Galli slinks wearily into the lobby and lies in one of the cushy recliners to let the green fade from her complexion.

Her aversion to flying notwithstanding, Galli cuts an eaglish visage, with sharp features and light gray plumage. The Twin Cities metro region nongame wildlife specialist for 19 years, she has been instrumental in the state's efforts to monitor bald eagles as they have rebounded from very low numbers to a population unprecedented in a half century. This statewide survey of nesting eagles--the first since 1995--will provide the best estimate of the number of breeding pairs in Minnesota. Aerial surveys later will determine the rate at which nests are producing chicks.

Surveys are being conducted not only in Minnesota but also in the rest of the Lower 48, where the eagle is now listed as threatened under the federal Endangered Species Act. The bald eagle has recovered so dramatically that the federal government has proposed "delisting" it throughout the United States. If it does, the state surveys will provide critical baseline information to gauge if remaining state and federal laws adequately protect the eagle.

For Galli, the survey and the impending delisting are cause for celebration. In the years following World War II, breeding eagles disappeared from areas where they once were common. In 1963 the National Audubon Society surveyed eagle watchers, interviewed state and federal wildlife managers, and flew surveys over the Missouri and Mississippi rivers in the first comprehensive attempt to estimate the number of nesting eagles. Results were not good. In all the Lower 48, where perhaps as many as 100,000 bald eagles once flew, the census could account for only 417 nesting pairs.

Scientists soon discovered that DDT and related insecticides concentrated in these top-of-the-food-chain predators. The compounds interfered with calcium metabolism, causing the birds' eggs to have paper-thin shells that broke before hatching.

News of the eagle's decline came at a time of social unrest generally and environmental activism in particular. Rachel Carson's elegiac Silent Spring appeared in 1962 with the warning that a "chemical barrage has been hurled against the fabric of life." The eagle was classified a federal endangered species in 1967. Canada banned DDT in 1970, and the United States followed suit two years later. The first Earth Day was celebrated in 1970.

During the bald eagle's darkest days, Galli was growing up in New Jersey, a city kid with few direct connections to wildlife--much less to bald eagles, which were virtually extirpated along the Eastern Seaboard. The high profile of environmental issues steered her interest in biology toward the natural world. As a master's student at Rutgers University, she studied the homing behavior of killifish in salt marshes. Later, as a nongame specialist in New Jersey, she monitored, inventoried, and protected nesting sites of terns and other colonial waterbirds, often by fencing them off from intrusive beachcombers.

Galli came to Minnesota in 1981 to work on its fledgling nongame wildlife program, funded by a checkoff on state income-tax forms. It was her first opportunity to work with bald eagles.

The largest concentration of breeding birds in Minnesota was found in the Chippewa National Forest. But the banning of DDT had had an immediate effect, and as Galli began conducting flyover surveys of the Mississippi River valley in southeastern Minnesota, the eagle was recovering. Nests had begun appearing along chains of lakes in central and eastern Minnesota, the bluffs of the St. Croix River, and the bottomland forests of the Mississippi. Wintering eagles appeared in increasing numbers in areas such as Reads Landing, where swift currents kept the Mississippi open and steep ravines provided protected roosting sites.

Initially, Galli tackled nongame projects for both southeastern Minnesota and the metro region. Several years ago, when a southeastern specialist was hired and Galli confined her work to the Twin Cities area, she regretted that she would lose contact with eagles. Instead, they seemed to follow her to town. During the last decade, nests, reported by an army of volunteer wildlife watchers, have appeared along the Mississippi to within a couple of miles of downtown St. Paul. Eagles have spread up the Minnesota River, where years ago they were never seen. Often, her phone would ring and Galli would talk to an excited caller who had seen an eagle from the window of a downtown office building.

"I think it's great," Galli says. "I think Minnesotans are excited about it too."

The bald eagle often serves as a poster child of conservation, its recovery cited as proof that the Endangered Species Act in fact works. In reality, the bald eagle's principal problem, DDT contamination, was relatively easy to solve. Created by technology, it was a problem tailor-made for science to fix. DDT poisoning was detected and diagnosed without much delay. Substitutes were found. The pesticide was banned. The eagle recovered while humankind blundered happily on. If only all endangered species could be such good patients.

Unfortunately, the bald eagle isn't out of the woods yet. "The work still goes on," Galli says. "The problems aren't all solved."

Some populations of eagles continue to have high levels of persistent contaminants. Heavy metals such as lead and mercury may poison the birds. Other pollutants may affect reproduction and development. Bald eagles on the shores of the Great Lakes produce fewer young than inland birds do, for reasons not well understood.

"We're still cracking out new chemicals, some of which we don't even know the consequences of," Galli says. "Our arrogance gets us in trouble, it seems to me. Some of the lingering problems are harder to solve."

Perhaps the most intractable problem of all is how humans share space with wildlife. Back up in the air, Galli and Petersen survey the remainder of the nests near Red Wing and then return upriver toward the Twin Cities. Throughout the southern suburbs, roads and houses carve the hills and bluffs into two or three lawns to the acre, each home surrounded by its 100 yards of heaven. By default, much of the region's wildlife seeks the river bottoms. This greenway between the Cities and the forested hills of the southeast is the area's last uninterrupted wildland. Development sprawls out from the Twin Cities and forces wildlife, Galli says, into "islands of habitat." The fix is not as straightforward as waving a wand, outlawing a chemical. To protect large tracts of wildland requires a change in lifestyle. And even if we were willing to make the change, it is not clear how we would accomplish it.

Galli and Petersen swing by the last of the nests. The number of vacancies disappoints her. On the plus side, they have found four new nests along the river. As they fly over each new nest, Petersen punches the GPS to lock the coordinates into the computer. Back at the office, Galli will download the coordinates into a computer program, which will spit out a map showing the precise location of each nest. Then Galli will try to discern if the nests replace nests in old territories, or if they belong to newly arrived eagles establishing new territories among established birds.

In the weeks ahead, nongame specialists in other regions will fly their own surveys. So will federal wildlife managers in the Chippewa and Superior national forests, Voyageurs National Park, and the state's national wildlife refuges. In the metro area, Galli or her colleague Steve Kittelson will fly additional surveys over the chain of lakes centered around southern Chisago County, and over the fairly new nests in the Minnesota River valley. Galli predicts that the surveys will reveal at least 700 active nests, placing Minnesota behind only Alaska, Florida, and Wisconsin.

After they land, Petersen asks when they'll fly again, weather willing.

Next week, Galli says.

"Will that be with you?" Petersen asks, "Or will that be with Steve?" He smiles, as if anticipating the answer.

"I think I'll let Steve do it," Galli says.

Greg Breining is Managing Editor of the Volunteer and author of Return of the Eagle: How America Saved Its National Symbol.