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Proposal would remove trumpeter swans, ospreys from state endangered and threatened species list

Weekly News Article Published: September 30, 2008 by the Central Office

MADISON – Populations of trumpeter swans, currently listed as a state endangered species, and ospreys, currently listed as a state threatened species, have recovered to the point that both species would be removed from the state endangered and threatened species list, under a proposal that will be the topic of an upcoming public hearing.

“The statewide populations of these two species have increased to the point where we are now confident that they no longer qualify as endangered or threatened under state statutes,” says Sumner Matteson, an avian ecologist with the Wisconsin Department of Natural Resources who oversaw the recovery programs for both species.

A proposed rule that would delete trumpeter swan from the Wisconsin endangered species list and the osprey from the Wisconsin threatened species list will be the topic of a public hearing October 20 at 4 p.m. in Room G09, Natural Resources State Office Building (GEF 2), 101 S. Webster St., Madison.

Both species will continue to receive protection under the federal Migratory Bird Treaty Act, Matteson says.

“The successful reintroduction of trumpeter swans and the successful recover of ospreys in Wisconsin is really a testament to the conservation partnerships between private organizations, businesses, scores of dedicated individuals, and state, federal, and tribal governments that have helped restore populations of these birds and ensure they will remain an integral part of Wisconsin’s biological diversity,” Matteson says.

In 1986, the DNR Bureau of Endangered Resources developed a recovery plan for the trumpeter swan that established a recovery goal of at least 20 breeding and migratory pairs by the year 2000. A reintroduction effort was very successful and the Wisconsin population has increased from zero in 1986 to 126 breeding pairs occurring in 20 Wisconsin counties in 2008.

Osprey were one of the raptor species whose populations were decimated by the insecticide DDT in the 1950s and 1960s. In the early 1970s the state’s nesting population numbered fewer than 100 pairs. Wisconsin listed osprey as a threatened species in 1972 and developed a management plan with a goal to increase the number of breeding pairs in the state to 300. That goal was achieved in 1990. The statewide population increased to just under 400 pairs from 1993 to 2002 and has been above 400 pairs since 2003.

Trumpeter swan

Trumpeter swans -- named for their resonant, trumpet-like call -- are the largest waterfowl species in North America. They were present in Wisconsin until the 1880s. But they disappeared from Wisconsin due to market hunting and feather collecting.

Under the 1987 trumpeter swan recovery plan, Wisconsin biologists flew to Alaska for nine consecutive years beginning in 1989 to collect surplus trumpeter swan eggs that were then hatched in incubators at the Milwaukee County Zoo. After the eggs hatched, the young swans were either placed in a captive-rearing program or decoy-rearing program until they were released to the wild.

Among the organizations that have provided support for the swan program were the Natural Resources Foundation of Wisconsin, the Milwaukee County Zoo, the U.S. Fish and Wildlife Service, General Electric Medical Systems, Windway Capital Corp., the Foundation of Faith, the Zoological Society of Milwaukee County, the Society for Tympanuchus Cupido Pinnatus, the federal Pittman-Robertson Federal-Aid-in-Wildlife Restoration Act, and the Endangered Resources tax check-off. The trumpeter swan Adopt-A-Swan program also provided additional funds.

Osprey

Ospreys are large birds, black-brown on top and white below. The osprey’s white head has a broad, black cheek patch and its tail is barred with brown. The osprey’s long, narrow wings are angled back at the wrist when it flies, and a black wrist patch contrasts with white underwings.

The osprey is the only bird of prey that plunges into the water to capture fish. In Wisconsin they feed primarily on panfish. They search for fish while flying 30 to 100 feet above the water. If they spot prey, they hover, then plummet down, plunging into the water feet first. Strong, curved talons and specialized spines on the bottoms of their feet help them hold onto the slippery fish. If they catch the fish, they quickly take off, juggling it in their feet until its head is facing forward into the wind.

Ospreys are summer residents in Wisconsin. They return to the state from southerly wintering grounds in the southern U.S. and Central and South America in mid-April to set up territorial breeding spots. They breed mainly in the lake regions of northwest and north central Wisconsin. A few nest along the Wisconsin River in the central part of the state.

Ospreys never were numerous in Wisconsin, but they nested in suitable habitat throughout the state. In 1972, use of organochlorine pesticides was banned in the U.S., resulting in a gradual increase in osprey populations.

Research in the mid-1970s showed that 10 percent of all osprey nests blew down each year. Thus, DNR biologists began constructing artificial nesting platforms, which are now used by two-thirds of Wisconsin’s ospreys.

DNR biologists have conducted annual aerial surveys to locate active osprey nests since 1973. Once a nest location was identified, biologists developed a management plan for the area to limit timber harvest, road building and other human disturbances within a quarter mile of an osprey nest. The DNR enlisted the cooperation of landowners to protect osprey nests on private lands.

The DNR Bureau of Endangered Resources had many partners in the osprey recovery effort, including American Transmission Company, Wisconsin Public Service Corporation. WE Energies, Northern States Power, Dairyland Power Company, Wisconsin River Power Company, Consolidated Water Power Company, Wisconsin Valley Improvement Company, Wisconsin Society for Ornithology, Wisconsin Audubon chapters, the Chequamegon and Nicolet Nation Forests, numerous conservation clubs, and many private landowners.

FOR MORE INFORMATION CONTACT: Sumner Matteson – (608) 266-1571

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