By Cate Harrington
“When we get strong southwest winds and falling air pressure during autumn, it’s a peregrine parade out here.”
That’s peregrine falcon researcher Rob Sulski talking about his raptor banding station at the Conservancy’s Chiwaukee Prairie Preserve on the shore of Lake Michigan.
For the last six years, Rob and Mike Jones have spent much of September, October and November in blinds at Chiwaukee, live-capturing and banding peregrines and other raptors. They are part of a network of volunteer bird banders in the United States who gather data about raptors to help conservation agencies and organizations like the Conservancy protect and improve habitat for these birds.
Chiwaukee Prairie is an excellent banding site because it provides ideal habitat during migration for long distance fliers like the peregrine falcon.
“The highest concentrations of peregrines are within 2,000 yards of the shoreline,” Rob said. “The open, sandy prairie at Chiwaukee makes it easy for them to spot and chase down their prey.”
Refueling Stations are Critical for Long Distance Fliers
Peregrine falcons are just one of hundreds of bird species that migrate through the Great Lakes region each year between their wintering grounds in warmer southern climates and their northern breeding grounds.
Their journeys are often long and arduous, and they need places to rest and refuel along the way. Without stopover sites, they face death from exhaustion and starvation.
Populations of some migratory birds have declined dramatically over the past 30 years due to loss of breeding, wintering and stopover habitats as well as collisions with buildings and other man-made structures.
For years, the Conservancy has protected breeding and nesting habitat for birds in Wisconsin and throughout the Great Lakes region. We have partnered with others to protect wintering grounds for birds in many other countries.
More recently, however, we have focused on protecting critical stopover sites in places like the Great Lakes, the Gulf of Mexico and the Atlantic Coast that are used by hundreds of millions of birds each year during migration.
Fire Escapes, Convenience Stores and Full-Service Hotels
There are three general types of stopover sites and all of them are important.
- Fire escapes like a freighter or a small island in Lake Michigan are places where birds can drop in and rest but there is little or nothing to eat.
- Convenience stores, are typically a little larger and have enough shelter and food for birds to refuel and continue migration.
- At full-service hotels like Chiwaukee Prairie, birds can rest for several days and “carbo load” before continuing the next leg of their journey.
To adequately protect all three types of stopover sites, we need to know where they are located.
In the Great Lakes region, the process to identify stopover sites took off in 2003 when the Conservancy convened a group of experts and, by 2006, developed a computer model to map the important migratory bird stopover sites in the western Lake Erie basin and make recommendations for protecting them.
Knowledge gleaned from bird experts was combined with Geographic Information System (GIS) mapping technology to predict where migratory birds were most likely to congregate on the landscape.
“For example, we know that birds congregate close to the shore where large insect hatches occur,” said Dave Ewert, Conservancy senior conservation scientist who led the Lake Erie mapping project. “So protecting shoreline habitat where these hatches occur is critical for migratory birds as well as other types of wildlife.”
Creating a Migratory Stopover Map for Wisconsin
The process used on Lake Erie served as a model for identifying important bird stopover sites in the Lake Michigan and Lake Superior basins here in Wisconsin.
Starting in 2006, Sumner Matteson and Kim Grveles at the Wisconsin Department of Natural Resources led the process, which was supported financially and with scientific expertise by the Conservancy. Many other partners also contributed their expertise to identify more than 36,000 acres of important migratory bird habitat and develop strategies to protect them.
“Now that we know where these important stopover sites are located,” said Steve Richter, Conservancy conservation director in southwest Wisconsin, “we’re incorporating them into our conservation plans for ecologically important places like the Green Bay Watershed, Chiwaukee Prairie and the Door Peninsula and looking for opportunities to protect them.”
Richter adds that people can help ensure safe passage for the warblers, waterfowl, raptors and other birds that herald the arrival of spring in Wisconsin each year.
“Birds are extremely vulnerable during migration, and habitat loss caused by development, invasive species and other land use changes can make their journeys even more difficult. Through their generous support, bird lovers can help the Conservancy protect those ‘full service hotels’ like Chiwaukee Prairie and Green Bay’s coastal wetlands, as well as other migratory stopover sites, which are absolutely essential to our feathered friends.”
You can read more about the Wisconsin Stopover Initiative to protect, conserve and enhance the habitats used by birds migrating through the Great Lakes at this link.
Cate Harrington is a senior conservation writer for The Nature Conservancy.