Trumpeter swans trending well in Minnesota

When Carrol Henderson interviewed in 1977 for a new job in state government — to head the Nongame Wildlife Program with the Minnesota Department of Natural Resources (DNR) — he asked about the prospects of reintroducing the trumpeter swan to Minnesota.

"Let's just say the response I got wasn't too encouraging because they had been written off as 'extirpated' since the 1880s, and early efforts to reintroduce trumpeter swans in the 1960s, while very important, had not been very successful," said Henderson.

Henderson got the job and pursued his dream to reintroduce the iconic species, though pushback continued. One DNR regional manager questioned if Minnesota had enough "adequate habitat" to support the bird, arguing, too, that he didn't want to invest "in a species that couldn't be hunted."

"I'm a stubborn, optimistic Norwegian by nature, so I stayed patient and waited for him to retire, and the rest is history," said Henderson, laughing.

Today, the estimated trumpeter swan population in Minnesota has grown to roughly 17,000. That is a quantum leap from the six to eight pairs that existed when Henderson, collaborating with officials from the University of Minnesota, the Trumpeter Swan Society, Hennepin County Parks (now Three Rivers Park District) and the U. S. Fish and Wildlife Service, drafted a restoration plan in 1982. The effort, whose original goal was to establish 30 swan breeding pairs, has been hailed as a model of collaborative conservation, rivaling successful species recovery efforts like the wild turkey and the bald eagle.

"Minnesota is a model of bringing together the right partners, the best technical expertise, and the dedication and passion of individuals, agencies, and organizations to bring back a species that had been gone for nearly a century," said Margaret Smith, executive director of the Trumpeter Swan Society, which helps pay for the state's aerial surveys. "When Minnesotans see trumpeter swans today, they are really seeing inspiration and hope that a species can be restored."

Native to Minnesota and the largest North American waterfowl species, trumpeter swans originally inhabited wetlands from Illinois northwest to Alaska. Throughout the 1800s, they were hunted for their meat, skin and feathers. During this period, swan habitat diminished as settlers moved across North America, including Minnesota, where swans eventually disappeared. By the 1930s, an estimated 69 trumpeters remained in the lower 48 states, living in the remote Red Rock Lakes area in southeastern Montana.

Attempts to restore the trumpeter swan population in Minnesota first began in the 1960s. That's when Hennepin County Parks released young trumpeters brought in from Red Rock Lakes National Wildlife Refuge in Montana. However, those swans suffered high mortality from lead poisoning, hitting power lines and illegal shooting.

Two decades later, Henderson hatched his state restoration project. The ambitious plan included collecting 50 swan eggs per year (from 1986-88) from Alaska, which had a healthy trumpeter population. The eggs were transported in special suitcases which were placed in the overhead bins during a first-class Northwest Airlines flight. The eggs were later hatched and reared at the Carlos Avery State Wildlife Management Area near Forest Lake. At age two, the swans were released in the vast wetland complexes near the Tamarac National Wildlife Refuge in northwest Minnesota. Over the years, the population has been supplemented with cygnets raised by several U.S. zoos, including the Minnesota Zoo.

"The population has continued to grow throughout the years and is now self-sustaining, which is very gratifying to see," said Henderson. "The great thing about the program's success is that it's been funded voluntarily by donations to the Nongame Wildlife Check-off line in your state taxes, which was passed into law in 1980. We couldn't have done this work without that revenue."

Over the program's 25-plus years, restoration costs have totaled roughly $515,000. Major swan releases ended in 2001. Today, trumpeter swans breed throughout the state, with highest concentrations in north and north-central Minnesota. Henderson said roughly 90 percent of swans winter-over in Minnesota, including on the Mississippi River in Monticello and the Otter Tail River near Fergus Falls.

"One of the biggest surprises of this restoration is that I expected the trumpeters, like other waterfowl species, to spread into prairie pothole country," said Henderson. "But they didn't. Instead, they dispersed northward into the northern boreal forest lakes country characterized by spruce and tamarack forests and remote lakes surrounded by bog mats."

Christine Herwig, DNR regional nongame specialist in Bemidji, said the agency will continue to closely monitor state swan populations. For the first time in state history this spring, Herwig and a pilot biologist flew census flights over four days exclusively for trumpeter swans in northeast Minnesota.

"Minnesota's population is growing and is the largest in the continental U.S., but there are still concerns we need to monitor," said Herwig. "We know trumpeters can be exposed to lead sinkers while foraging."

The DNR aerial survey is part of a larger federal assessment called the North American Trumpeter Swan Survey. It's conducted every five years by the U.S. Fish and Wildlife Service. The next survey is scheduled for 2020.

As for Henderson, he's beyond pleased by the restoration effort. "It's a fulfillment of a dream," he said. "If I never did anything else during my career but this trumpeter swan work, I'd be more than happy."

Tori J. McCormick is a freelance writer from Prior Lake. Reach him at torimccormick33@gmail.com