Celebrating the future and appreciating the past
From degraded land to essential habitat: Agassiz National Wildlife Refuge turns 80
March 23, 2017
Waterfowl at Agassiz National Wildlife Refuge. Photo by Gary Huschle/USFWS.
When you look at Agassiz National Wildlife Refuge, it’s hard to believe that 80 years ago it was severely degraded from years of deforestation, draining, and overtrapping. Today, the refuge offers a variety of habitat from oak savanna and sedge meadow to coniferous bog wilderness. Visitors can see healthy populations of trumpeter swans, buffleheads, sandhill cranes and more.
Agassiz got its start in 1937 when President Franklin D. Roosevelt designated Mud Lake Migratory Waterfowl Refuge as a breeding ground for migratory birds and other wildlife. In 1961, the refuge was renamed, but the purpose remained the same.
The refuge lies in northwestern Minnesota, surrounded by forests and tallgrass prairies. More than three-quarters of Minnesota’s original wetlands were comprised of sedge meadows and were indispensable habitat for plants like lilies, irises, and native orchids. Because of agricultural production and other types of development, these wetland landscapes have become increasingly rare and biologists are working to restore them. With the help of the best wetland scientists in the country and other partners, we are doing tremendous work to restore wetland functions and cycles to a 10,000 acre wetland.
While the refuge has vast acres of wetland habitat, biologists battle against invading non-native cattails and grasses. These invasives, along with the compounding effects of sediments from converted agricultural lands, clog wetlands and alter the natural hydrology of the region. It’s important that we fight against invasives to protect the sedge meadows that provide foraging and nesting habitat for a variety of wetland-dependant bird species including Le Conte’s sparrows, sedge wrens, sharp-tailed sparrows, and yellow rails.
The wilderness area includes more than 2,300 acres of coniferous bog habitat, home to olive-sided flycatchers, Connecticut warblers, native orchids, ferns and even carnivorous plants. Diverse habitats welcome all sorts of wildlife, including a variety of reptiles, amphibians, 49 different mammals and almost 300 species of birds.
Ducks are a big part of the bird diversity at Agassiz, with 17 species breeding on the refuge. This includes the largest population of breeding bufflehead ducks in Minnesota. All told, roughly 7,000 pairs of ducks nest here, resulting in about 13,000 ducklings each year!
Most people come to the refuge to watch birds and look for wildlife. In the spring, summer and fall, you’ll likely see a variety of grebes, American bitterns, nesting bald eagles and sharp-tailed grouse. Very rare sightings of Eurasian widgeons and long-tailed ducks have also been reported.
The refuge is home to much more than birds. Two packs of gray wolves live on the refuge, but sightings are rare given their secretive nature. If you’re lucky, you might see black bears, elk, pine martens, fishers, river otters, bobcats, and short-tailed weasels.
Moose are even more elusive at the refuge, but that has less to do with secretive behavior and more to do with environmental changes. Moose populations peaked in 1982 at roughly 4,000 across northwest Minnesota and 437 on the refuge. The latest survey in 2007 documented only 100 moose total, with about half at Agassiz. While researchers still haven't pinpointed any one variable that marks this decline, a study in the late 1990s concluded that the compounded stress of warmer winters and increased parasites like winter ticks, liver flukes and brainworm may have rendered this part of the state inhospitable to moose.
Since being designated as a wildlife refuge 80 years ago, the landscape at Agassiz has made an impressive transformation. As biologists and land managers continue to reestablish natural systems, the refuge will become an even more vital part of America’s biological diversity.
Learn more about the refuge and plan your visit: https://www.fws.gov/refuge/agassiz/
The 1959 refuge narrative included this photo and caption: This portable tower is known as Dills Duck Detector. It was made to better count and identify breeding pairs. Duplicate records were kept in the tower and in the cab. Close agreement was obtained provided the vehicle did not exceed 10 mph. Marv Mansfield in the tower and Gary Hofmaster in cab. Photo by Herb Dill/USFWS.