BABCOCK, Wis. — With a wingspan of more than 7 feet, the trumpeter swan is North America’s largest waterfowl.

But even an immense white bird can do a pretty good job of hiding in a Wisconsin wetland.

“Try behind those bulrushes,” said Randy Jurewicz, pointing from his canoe to a notch in the reedy shore of the cranberry reservoir.

Meg Ziegler cranked out a few hard strokes, and her kayak glided into the shallows.

Seconds later, a 26-pound adult and a 17-pound juvenile popped into view.

At least one of the trumpeter swans had been snorkeling under the tea-colored water to avoid detection.

Soon more “swan rustlers” converged in boats and helped surround the birds, which are making a strong comeback here.

The workers were with the state Department of Natural Resources — Jurewicz is a retired endangered resources manager and Ziegler is a wildlife technician — or volunteers.

Hands were placed on the backs of the birds to restrain them and, in a well-practiced maneuver, slipped around both sides to grasp leathery black legs.

The feathery bundles were then hoisted into canoes and kayaks for a trip to a shoreline processing station.

Once captured, the birds sat stoically as their long, straight necks periscoped between the knees of the paddlers.

“It’s a privilege to get this close to such magnificent birds,” said volunteer Anne Lacey, who also works at the International Crane Foundation in Baraboo.

A wiped-out species

Just 25 years ago, it would have been rare to see — and unthinkable to capture — a trumpeter swan here.

Hunting and habitat loss wiped the birds out of the state in the late 1800s.

The swan’s resonant, sonorous call — the source of its name — was absent from Wisconsin for more than 100 years when the DNR began its Trumpeter Swan Recovery Program in 1987, according to state wildlife officials.

Thanks to the innovative program, the birds have come back from zero in 1987 to between 1,000 and 1,500 in Wisconsin this year.

The trumpeter was removed from the state’s endangered and threatened species list in 2009.

Over the course of just one hour on one Wood County wetland, boats returned from all corners of the reservoir with precious, live cargo: Six trumpeters — the adult and five cygnets — were captured.

The goal was to band the birds for population studies and take measurements and blood samples.

The roundups are done in late summer, just before the cygnets begin flying. An occasional adult is caught, too, during its flightless molting period.

The DNR conducted the banding outings each year since 1997. But thanks to the success of the trumpeter recovery program, state wildlife managers recently announced that the 2012 swan capture was the last.

“It’s the end of an era,” said Sumner Matteson, a DNR ecologist who co-wrote the trumpeter swan recovery plan in 1986. “But it’s a happy ending.”

Like most species of wildlife in North America, the trumpeter declined through the 19th and early 20th centuries. The trumpeter was killed for its flesh, its skin and its feathers. The birds’ skins were fashioned into powder puffs. Famed naturalist John James Audubon favored trumpeter swan quills for his drawing pens. The feathers also were used to adorn hats.

By the mid-1900s, only a small population of trumpeter swans existed in Montana and a larger group in Alaska.

To help restore regional populations of the species, the Trumpeter Swan Society formed in 1968.

Restoration efforts

The first Midwestern trumpeter recovery effort began in Minnesota in the late 1960s with the transfer of adult birds from Montana.

The Wisconsin trumpeter reintroduction project got its start in 1987. Initial efforts to use mute swans to hatch and raise trumpeter young were largely unsuccessful.

Starting in 1989, the DNR implemented a decoy- rearing technique. The eggs were obtained from Alaska by Jurewicz, Matteson and Terry and Mary Kohler of Windway Capital Corp. in Sheboygan, Wis.

The Kohlers flew the aircraft and donated their time.

With approval from the U.S. Fish and Wildlife Service and Alaska officials, the Wisconsin crew was allowed to take eggs from trumpeter nests, always leaving at least two eggs for the pair to raise.

Eight trips followed, each yielding up to 50 trumpeter eggs. Pat Manthey, a DNR avian ecologist, also traveled with the egg-collection group for several years.

The trumpeter eggs were hatched at the Milwaukee County Zoo.

And in a captive-rearing phase of the project, cygnets were raised on ponds at GE Medical Systems in Pewaukee, Wis.

The ponds were closely monitored and, because they had been dug recently to serve as a source of water in case of fire at the complex, had no lead shot and were ideal for young swans. Lead shot is a source of poisoning in water birds and now is banned for waterfowl hunting.

As the trumpeters matured and dispersed around Wisconsin, they began nesting and raising their own young. The state’s recovery project had an initial goal of 20 breeding and migratory pairs of trumpeters; 44 were recorded in 2000.

6 percent annual growth

Since then, through entirely natural reproduction of wild birds, the Wisconsin trumpeter population has grown about 6 percent annually, according to DNR records.

Unlike the non-native mute swan and the most ubiquitous Wisconsin waterfowl, the mallard and Canada goose, trumpeter swans don’t prefer to nest in suburban or urban settings.

The big birds require more space and remote areas away from human activity.

Trumpeters generally need at least 8 to 15 acres of open water for security and at least 5 acres of shallow wetlands for feeding, according to a habitat study produced by the Wyoming Department of Fish and Game.

The wetlands should produce “extensive, luxuriant and diverse stands of submerged aquatic vegetation,” according to the study. Preferred food items include sago pondweed, arrowhead and wild rice.

Strong comeback

The banding project is ending as the trumpeters have reached new heights in the recovery program.

In 2012, biologists found 214 nesting pairs of trumpeters in Wisconsin, according to a DNR report. The mated pairs produced at least 373 cygnets.

Both figures are records for the trumpeter comeback in Wisconsin.

The banding project has helped researchers identify key trumpeter habitat and learn about the birds’ habits and longevity.

Once lakes freeze in Wisconsin, most trumpeters from the state migrate to wintering areas in Illinois, Indiana, Iowa and Missouri. Some will overwinter in open water on the St. Croix and Wisconsin rivers.

The farthest a Wisconsin trumpeter has traveled is to northern Texas.

In late November, the Wisconsin population of trumpeter swans is scattered in western, southern and central Wisconsin, Matteson said. Eighty-six trumpeters were recently sighted on a pond in Polk County.

The mild fall weather has allowed the birds to remain in Wisconsin.

Further monitoring

Although the banding project has ended, the DNR plans to monitor the trumpeter population every five years.

Aircraft will be used to count the birds, Matteson said.

“The trumpeter swan program has been the most challenging and the most rewarding initiative that I have been involved with in my career,” said Matteson, a DNR employee for 30 years.

In “A Sand County Almanac,” Aldo Leopold said conservationists should measure success not only by the number of fish and game taken, but also ask: “How can management restore the threatened rarities, like trumpeter swan and whooping crane?”

“Hundreds of Wisconsinites answered that question and contributed to this project,” Matteson said. “The dividends will be visible for generations to come.”