On Jan. 5, 1996, at minus 24 degrees, I sat on the ice on the Mississippi River near Monticello, watching and photographing a flock of about 50 trumpeter swans. Some swans floated in a small pool of water; others rested on the ice, their bills tucked tightly under their wing coverts. Steam rose from the frigid water as frosty clouds of fog floated over the river. Crystalline layers of hoarfrost covered tree branches. Sunbeams illuminated the swans as they alternately materialized and vanished in the fog. Every few minutes a swan rose to stretch and flap its wings, creating an angelic form—a vision of swans.

This enchanting natural scene had been missing from Minnesota for more than a hundred years. Even more rewarding for me to realize: Some of those swans were derived from eggs I had collected in Alaska as part of a project to reintroduce trumpeter swans in Minnesota.

Trumpeter swans had disappeared from the American landscape so early in our history that their memory was relegated mainly to museums, place names like Swan Lake, history books, and literature such as E. B. White's The Trumpet of the Swan. It appeared that the trumpeter swan had a past but no future.

Fortunately, the story does not end with this gigantic bird's disappearance from the state. With patience, persistence, and optimism, wildlife biologists and volunteers found a way to bring the world's largest waterfowl species back to Minnesota.

Big Downfall.

The trumpeter swan (Cygnus buccinator) weighs up to 35 pounds and stands up to 4 feet tall with a wingspread approaching 8 feet. Its resonant trumpeting calls can be heard over a half-mile away. The loud call is made possible by a loop of windpipe inside the breastbone. This extra-long trachea is, in effect, a nearly 3-foot-long trumpet, stretching from lungs to bill.

Adults have snow-white plumage with black legs and a black bill. Juveniles have pearly-gray plumage and pinkish bills in their first year. These birds can live for more than 25 years.

Trumpeter swans' large size, conspicuous white plumage, and thick down contributed to their historic demise. Subsistence use of swans as food by Native Americans would have occurred for thousands of years without diminishing the species. But European fur trappers and settlers hunted swans not only for meat, but also for swanskins and swan's-down. The bird's long wing feathers made popular writing quills. Artist John James Audubon preferred trumpeter swan quills for drawing the fine details of songbird feet and claws.

Fur buyers shipped swanskins to Europe to be cut up and sold as ladies' powder puffs. In 1806 the Hudson's Bay Co. first reported swanskins in their sales. From 1853 through 1877, the company purchased 17,671 swanskins, most from trumpeter swans. However, by 1877, swan populations were greatly reduced, and the company reported purchasing only 122 swanskins.

Trumpeter swans were disappearing from wetlands in Canada and the northern United States. Minnesota was a major portion of their U.S. range. The Dakota called a lake near Mankato Manha tanka otamenda, meaning "Lake of the many large birds." On July 13, 1823, Count G. E. Beltrami encountered adult swans and cygnets on those same waters—now called Swan Lake—providing the first nesting record by European explorers. But there were no nest records after 1885. Trumpeter swans had become extirpated in Minnesota, and biologists feared the species would become extinct. By 1932 only 69 trumpeter swans survived in the continental United States, mainly in Montana.

Restoration Plan.

In the 1960s Hennepin Parks began a decades-long effort to reintroduce trumpeter swans to Minnesota. Their goal: Establish a free-flying flock of 100 swans with 15 breeding pairs. The Department of Natural Resources built on the success of Hennepin Parks, now known as Three Rivers Park District. The 2015 survey of trumpeter swans in Minnesota recorded 270 swans in the five-county metro area, including 56 nesting pairs.

The DNR launched its Nongame Wildlife Program in 1977, and at first the state agency lacked funds for a swan restoration project. In 1982 the first donations received from the DNR Nongame Wildlife checkoff became available. As DNR nongame wildlife supervisor, I found my mind swirling with possibilities for helping beleaguered wildlife. University of Minnesota ornithologist Jim Cooper and I wrote a proposal for restoring trumpeter swans. On June 10, 1982, the DNR published the plan.

DNR Wildlife chief Roger Holmes specified that trumpeter swans were being reintroduced to restore an integral part of our state's biological diversity and not for eventual designation as a game species. He also specified that areas occupied by swans would not be closed to waterfowl hunting: It was up to hunters to learn to identify the protected swans. The consequences of shooting a trumpeter swan may include fines up to $3,000 and confiscation of firearms.

There was no playbook for this project because Minnesota was the first state to proceed with a major trumpeter swan restoration. We needed to perfect techniques for collecting, transporting, and hatching swan eggs and caring for the downy cygnets. Steve Kittelson, our ace biologist, worked out the details.

Trumpeter swan eggs require 33 to 34 days of incubation. We needed to collect the eggs when they were between 3 and 4 weeks old, so the developing embryos would be strong enough to endure minor jostling and slight variations in temperature when transported.

North to Alaska.

We would collect eggs in June 1986 on wetlands west of Fairbanks, Alaska. My assistant was Dave Ahlgren, a DNR volunteer and pilot for Northwest Airlines. Ahlgren and Northwest vice president Bill Wren arranged for our air travel to Alaska as well as our return via first class with trumpeter swan eggs.

For carrying the eggs, Kittelson adapted the suitcase design used by the U.S. Fish and Wildlife Service to transport whooping crane eggs. Each suitcase contained foam liners with hand-carved cavities for 12 eggs. Small channels between cavities allowed air circulation from a battery-powered fan in the end of the suitcase. Four old-fashioned hot-water bottles would be laid over the eggs to maintain their temperature at about 100 degrees. We would replace the water every two hours with hot water from the plane's coffeemaker.

For egg collecting, U.S. Fish and Wildlife Service pilot Rodney King selected Minto Flats, a vast wetland complex with more than 1,000 swans at that time. King had mapped nest locations and selected lakes that would allow access with his Cessna 185 floatplane. He'd calculated the stage of incubation so we could collect eggs that were within 10 to 15 days of hatching.

With great anticipation, Ahlgren and I flew to Anchorage on June 7. We traveled to Fairbanks where we joined King. For the final leg of the trip, he flew us to a log cabin 40 miles west of Fairbanks in Minto Flats. On June 10 we took off to collect the eggs. The aerial view of this wilderness wetland was awesome. We saw bald eagles, black bears, moose cows with calves feeding in shallow water, and then our first swan nest. A pair of snow-white swans glowed like pearls against deep blue waters. One swan was incubating on the nest mound while the mate swam nearby.

24-Hour Egg Marathon.

King, Ahlgren, and I landed on the small lake and taxied to the swan nest. We collected eggs and got ready for takeoff. But the wind had died, and the water was glassy smooth. That was bad. A floatplane needs some chop on the water to break the surface tension that bonds the floats to the water.

King taxied to the nearby shore, got out, and turned the plane around. Then he began takeoff. Two-thirds of the way across the lake, the floats had not broken free of the water. He shut down the motor, and we thunked into the opposite shore. King got out and repeated the maneuver. Again, we failed to lift off.

King turned to us and said, "One of you will have to go." We decided that Ahlgren would return to the cabin so he could boil water to keep the eggs warm. As the plane taxied away from my new island home, King threw me a sleeping bag. He smiled and said he thought he could find his way back.

About an hour later, King returned and we flew to other lakes with nesting swans. At each one, King landed artfully and taxied near the nest. With chest waders, I entered shallow water and stepped onto the bog mat to approach the nest. Several times I went through the bog mat and really cold water poured over the top of my waders.

At the nest, King and I labeled each egg and candled it to ensure it was fertile. We selected two live eggs to leave in the nest and took the balance of the clutch—usually three to five eggs. Each time we filled our egg suitcase, we flew back to the log cabin where Ahlgren was filling hot-water bottles to keep the eggs warm.

In the light of that long Alaskan day, we visited 16 nests and collected 50 eggs. At 7:45 p.m. we returned to Fairbanks. Ahlgren and I caught flights to Anchorage and then Minneapolis. We tucked the egg suitcases into the first-class overhead bins. Every two hours, as curious passengers peered over our shoulders, we took down the suitcases and replenished the hot-water bottles.

At 10 a.m. on June 11, we arrived at Carlos Avery Wildlife Management Area and placed the eggs in incubators.

Cygnet Psychology.

Once the eggs arrived, Kittelson took over the hatching and rearing process. Using pheasant-egg incubators, he kept the eggs at 100 degrees, misted them to maintain 60 percent relative humidity, and turned them regularly, as parent swans would do in the wild. Kittelson weighed each egg daily to ensure that it showed steady weight loss as the yolk and white transformed into a cygnet.

As cygnets neared hatching, Kittelson kept the eggs in close proximity so they would imprint on each other's peeping—and not accidentally on voices of people. After the cygnets hatched, they spent one more day in the incubator to "fluff out" and bond with each other. Then Kittelson moved the cygnets to indoor brooders. For their first several weeks, he fed them a well-balanced diet of waterfowl starter feed. If their feed contained too much protein, their wrist joints would become twisted and they would never be able to fly.

Next, the cygnets were moved outdoors to a pen in a shallow pond. The pen was covered above and on the sides with wire-mesh fencing to protect the cygnets from owls, eagles, raccoons, mink, and other predators. At the end of their first summer, as they approached the size of adult Canada geese, the swans had their wing feathers clipped, and they were placed in two separate fenced pens, each with an aerated pond. Why two pens? When restoring Canada geese in the 1960s, waterfowl biologists learned that geese raised together in one pen would not mate with each other.

Released at Last.

An important question in restoration: What age to release swans? Because natural mortality is typically high in a trumpeter's first year, we decided to hold them in captivity until 23 months of age. Because trumpeter swans normally select a mate in their third year and begin nesting in their fourth year, this release age would give the swans a year to become familiar with their release area before they reached breeding age.

In 1987, after five years of planning, egg collection, and cygnet rearing, we began the most important part of our project—releasing swans in their new "homes." We had gathered swans for our first major swan release with 21 juveniles from the Minnesota Zoo, the Brookfield Zoo in Chicago, and Three Rivers Parks. The swans had their wings clipped so they could not fly away when released in spring. New flight feathers would grow back in late summer. Trumpeter swans imprint on the first place that they fly from, so to them Minnesota would be home.

Peggy Hines Peters, DNR wildlife technician, had selected some outstanding wetlands around Tamarac National Wildlife Refuge near Detroit Lakes for release of the swans. But how would the flightless swans get there? Transporting the swans in large dog kennels in a truck would have risked injuring their legs during the bumpy ride. So we needed another option. Thanks to my military background, I decided to call the Army Reserve at Fort Snelling and ask if they could organize a transport training flight to deliver 21 swans to northwestern Minnesota. They must have thought I was nuts and would have nothing to do with it. Then I called the Minnesota Air National Guard and posed my idea of a training flight with a cargo of swans. They loved the idea.

Recalling my graduate school lessons in working with the media, I realized this event would be newsworthy as the First, Biggest, and Most. So I contacted ABC, NBC, and CBS news in New York and pitched the swan release as the first and largest in U.S. history. Three members of the CBS news team came to cover the first release of 21 swans.

On April 22, 1987, as we opened their kennels, each pair of swans walked into the water, swam out a few feet, rose up, and flapped their wings. It was an incredible feeling to see the swans begin their new life in Minnesota.

On April 13, 1988, DNR Nongame Wildlife released five trumpeter swans at Swan Lake, Manha tanka otamenda, in Nicollet County. On April 20, 1988, we repeated the release scenario with 40 swans in northwestern Minnesota. ABC news sent out a crew with reporter Roger Caras. At a lake on the White Earth Reservation, local children released the swans. The story aired on ABC on May 10, 1988. Caras estimated about 40 million people watched. As the broadcast showed the final pair of swans swimming off, Caras commented: "The magnificent trumpeter swan, gone from the lakes of Minnesota for over a century, has been summoned home. … They are being brought back by the citizens of Minnesota with funding from a checkoff system on their state tax forms. … The swans are gifts that Minnesotans have given themselves."

Cygnets from Alaskan eggs were released in 1988, 1989, and 1990. Juvenile swans rescued in Alaska in 1992 were also released in spring of 1994. From 1987 through 1994, we released 217 swans. In 1995 we began an extended effort to release trumpeter swans in southern Minnesota, and we released another 139 swans in the Heron Lake area between 1995 and 2012.

Counting Swans.

Our initial restoration goal was 30 pairs of breeding swans in the state. We reached that goal in 1991. The swan population continued to grow in northwestern Minnesota. However, we had little information on nesting ecology, nesting success, and habitat preferences.

DNR nongame wildlife biologist Katie Haws collaborated with Kris Spaeth, a graduate student at Bemidji State University, to study nesting swans. Researchers found 18 nests in 2007 and another 27 in 2008. Among the 39 successful nests, 197 cygnets hatched from 225 eggs—a very impressive total.

Swans nested in 29 lakes and 16 smaller wetlands. They preferred water bodies of less than 60 acres with shallow cattail edges and forests surrounding at least three-quarters of the shoreline. Cattail tubers provided abundant food. Such smaller bodies of water had less disruptive wave action, shoreline development, and boating traffic.

Nest predation of trumpeter swans was almost nonexistent. Only 1 percent of the eggs were taken by a predator—possibly an otter. Trumpeter swans are extremely aggressive and effective in driving predators, even Alaskan brown bears, from their nests.

I had originally expected the swans released near Detroit Lakes to expand their range southward into the prairie pothole country of Otter Tail County. Instead, to my surprise, the swans ventured north and east, where they nested on lakes with bog mats amid forests of black spruce and tamarack—the kind of habitat where I had collected the eggs in Alaska.

In 2008 Minnesota had an estimated 3,600 trumpeter swans. In 2015 DNR nongame wildlife biologist Christine Herwig led a survey that tallied 17,021 swans. This suggests that 1,700 nesting pairs produce about 5,000 cygnets in a year. Wow!

Old Friends.

On Jan. 10, 1997, I returned to the Mississippi River near Monticello to observe trumpeter swans at their favorite wintering site by the home of Jim and Sheila Lawrence. I sat on the rocks at water's edge with my camera in hand. In the middle of the river, one swan parted from the flock and swam toward me. I photographed the swan as it drew closer—within 50 feet, then 40 feet, then 20 feet. Finally, it swam so close I had to turn my camera sideways to get the whole swan in the viewfinder. Then the swan stepped from the water, and I could see a leg band. I focused on the band and took a photo. It was swan number 619-71888.

As the swan stood silently looking at me, I began to talk to the swan in a calm, low voice. I carried on small talk for about five minutes. Finally, the swan turned away, entered the water, and rejoined the flock.

Back at my office, I looked up the swan's band number and discovered I had collected this swan as an egg in Minto Flats on June 10, 1988. We had reared that cygnet and released it on North Chippewa Lake in Tamarac NWR on May 23, 1990.

I can surmise only that the swan on the river had stopped by to say, "Hi, Dad. And thanks."

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