Bird’s-eye view: What 50 years of research reveals about waterbirds in the Apostle Islands

Sumner Matteson uses a spotting scope to look for piping plovers on Long Island

June 26, 2024

2024 is a milestone year for the waterbirds of the Apostle Islands National Lakeshore and for the scientists who study them. It is also a time for concern as some waterbird populations are now significantly smaller than they’ve been over the past half century. Others are simply gone.

The Apostle Islands and Chequamegon Bay have served as nesting areas for herring gulls, ring-billed gulls, common terns, black terns, cormorants and great blue herons. These birds are colonial, meaning that they typically nest in colonies or groups. As rugged and remote as most of the islands are, Wisconsin Department of Natural Resources scientist Sumner Matteson told Friends board member Neil Howk that he’s seeing a decline for every colonial waterbird species in the Apostles. The question is why. The possible explanations vary by species.

Sumner paddling to Gull Island in a small zodiac raft

Sumner paddling to Gull Island in a small zodiac raft

In 1974, Matteson and former UW graduate student James T. Harris initiated one of the first surveys to monitor populations of gulls and terns in the islands and along the Wisconsin shore of Lake Superior.

A grant from the Sea Grant program at the University of Wisconsin enabled them to expand the survey to include all colonial waterbirds.

The most-recent survey was completed in June, 50 years after the first.

Matteson says the value in doing these surveys every five years over the decades is developing a long-term data set. And those statistics reveal some interesting – if not troubling – trends.

Herring gull population is down 65%

Gulls on Eagle Island

Herring gulls on Eagle Island

Matteson says herring gulls reached a peak of about 1,300 nesting pairs in the islands. He says the gulls were nesting on 19 islands in 1975; this year they are nesting on only six. He says the herring gull population is down 65% to 460 nesting pairs, including only 307 on Gull Island.

Matteson says the growing presence of American bald eagles may be a factor. “These past couple of weeks we saw on almost every island an adult bald eagle. Not always a nest, but it was amazing to see so many eagles, which is a great representation of the species’ recovery.”

He adds that “there are now peregrine falcons nesting in the islands, likely at 4 sites, which was only a fantasy back in 1974. It could be that the peregrines and eagles are taking gulls. We don’t know that for sure, but that could be a factor.”

Matteson also says “contaminants, both legacy contaminants such as DDT, DDE, and PCBs could be a factor as well as the new suite of modern contaminants. Climate change could be another factor. Not so much habitat loss in the Apostles, but something occurring on the wintering grounds. We really don’t know what the reason is.”

Cormorant population is down 58%

Sumner beneath cormorant colony on Eagle Island

Matteson standing below cormorant nests on Eagle Island

The cormorant population is down 58% population since 1994. “They used to nest on Gull and Eagle islands – as many as 735,” Matteson says. “They’ve declined to only 307 at one site – Gull Island.”

“It could be related to the emphasis over the last 15 years to control cormorants at aquaculture facilities in southern states where cormorants winter, as well as the efforts to control breeding numbers in the Great Lakes in response to concerns about their impacts on fisheries and island habitats.”

Ring billed gull nests remain rare in the islands

This year’s survey found no ring-billed gull nests. Matteson says their numbers have always been low and sporadic on the islands, even though there are thousands to the west in the St. Louis River estuary and the birds are well-represented in Chequamegon Bay at the breakwater.

Black terms no longer nest on Lake Superior shores

Matteson says black terns are basically gone from the entire Lake Superior shore as nesting birds. They haven’t nested in the islands, but used to nest in the Kakagon sloughs, Fish Creek Slough, and also in Allouez Bay.

Great blue herons no longer nest in the islands

Great blue herons tended 54 nests on Eagle Island and 31 nests on Madeline Island back in 1984. These large, long-legged birds no longer nest on the islands.

Sumner Matteson banding piping plover chicks with Julie Van Stappen

Sumner Matteson banding piping plover chicks with Julie Van Stappen

Colonial waterbirds aren’t the only species being counted and studied

Matteson takes part in banding young piping plovers hatched in the Apostle Islands and at other Lake Superior nesting sites. He’s also participated for several years in a breeding bird survey on Raspberry Island.

Matteson says his favorite memory from his time doing research in the park happened while doing a fall migration study on Outer Island. 
“Each morning we’d get up at dawn and go out and sit in the dunes (on the Outer Island sandspit) and observe what migrants were passing overhead coming out of the forest and also from the sky.”

He says, “I remember sitting completely still in the quiet and observing a warbler fallout… blackburnian warblers, black-throated green warblers, American redstarts, Nashville warblers, Magnolia warblers…landing at my feet! I’ll just never forget that, having them come down, landing in the dunes, being surrounded by all these incredibly beautiful warblers. Warblers are the crown jewels of the bird world and having all of these jewels falling all around me…feathered jewels falling all around me…spectacular. That experience is indelibly etched in my memory. What a treat.”

The Apostle Islands National Lakeshore is recognized as an “Important Bird Area” (IBA) by the Wisconsin Bird Conservation Partnership. The lakeshore provides important habitat for bird populations that consider the islands home, and those passing through during spring and fall migrations.

Sumner Matteson walking with Peggy B urkman looking for piping plovers on Outer Island

Sumner Matteson walking with Peggy Burkman looking for piping plovers on Outer Island

Matteson credits decades of cooperation from the National Park Service for the success of the research. He says he couldn’t ask for a better partnership. “Too many names to mention over the decades, but I have to begin with the park’s first Chief Naturalist, Warren Bielenberg, who was absolutely 100% supportive and encouraging. We couldn’t have had a better park representative to work with than Warren. He was absolutely outstanding. And over the years, park ecologists Merryll Bailey, Bob Brander, Julie Van Stappen, and the present very capable staff of Peggy Burkman, Kasey Arts, and Izzy Vetterman. And I cannot overlook the years of excellent boating support, the skills and contributions of the legendary Dave “Coop” Cooper. The fantastic support of National Park Service Apostle Islands National Lakeshore staff has been the most rewarding aspect for me over all of these decades.”

About Sumner Matteson, Avian Ecologist for the Bureau of Natural Heritage Conservation, Wisconsin DNR

Sumner participates daily with other DNR staff in fielding questions about endangered, threatened and non-game birds, and is responsible for writing twelve species accounts for the upcoming Wisconsin Breeding Bird Atlas.

He currently conducts surveys of breeding state endangered terns… the common tern, Forester’s tern, black tern, and Caspian tern on Lake Superior, Lake Michigan, Lake Puckaway, and the Winnebago pool lakes. He participates in annual surveys and monitoring of black-necked stilts that are breeding in relatively large numbers now at the Horicon National Wildlife Refuge and represents the state of Wisconsin on the Mississippi Flyway Council’s Nongame Bird Technical Section.

He also serves on the Ferry Bluff Eagle Days Planning Committee for Bald Eagle Days in Sauk Prarie Wisconsin, participates annually in the National Audubon Society’s Christmas Bird Count in December, serves on the Natural Resources Foundation’s Great Wisconsin Birdathon’s planning committee. For 25 years Matteson directed the very successful Wisconsin Trumpeter Swan Recovery Program.

Sumner presented research on piping plovers during the park’s 50th Anniversary Resource Stewardship Symposium. You can watch that presentation on our website.

Scariest and most humorous memories

In talking with Friends board member Neil Howk, Matteson reminisced about the scariest experience he’s had in the islands. He says he was canoeing from Second Landing off of Highway 2, near Ashland, to Long Island in early July, 42 years ago.

Matteson says, “We were going to check on the status of piping plover productivity, and when we departed in late afternoon it was breezy with the wind at our backs (which was nice), but with clouds beginning to build in the west. I was in the stern. I had one fellow in the middle and another in the bow.

We had about a 5½ mile canoe paddle to the southern end of Long Island, and about a mile out the weather began to change. Clouds rolled in quickly from the southwest and winds began to increase quite a bit. Soon they became strong, but still at our backs. If you’ve ever been out on Lake Superior when a squall comes up, you’ll know what I’m talking about. At mile three, the storm was upon us, and the winds became gale force with whitecaps and three to four foot waves…and building. It took all of my years of canoeing under my father’s tutelage to keep the canoe from turning broadside (to the waves) and capsize. By mile four, we simply stopped paddling. In the driving wind and rain, all I could do was steer the canoe because the winds had become so fierce there was really no alternative. The wind was carrying the canoe faster than we could paddle. Again, this was testing my skill as a canoeist to ride the waves and keep the bow from turning broadside, which with a full load was becoming exceedingly difficult.

The wind drove the canoe forward with an intensity that I’d never experienced before or since. So powerful was the wind that it carried us up onto the beach on Long Island. We quickly turned the canoe over and took shelter from the storm until it had completely passed…not more than 10 minutes later. All three of us were witness to the sudden fury of Lake Superior, and more than grateful that we survived that experience.”

Neil: On the flip side, do you have any humorous experiences in the islands that come to mind?

Sumner: “This story is a reflection of my quirky sense of humor. But back in 1974, 50 years ago, when I was just a young lad and looked a little like Charley Manson’s brother (laughter). The park service didn’t have any boats we could use at that time. So the boat we were using was rented from the Apostle Islands Marina. We were out all summer long, and on one trip the boat broke down between Basswood and Hermit islands late in the early evening as we were returning to Bayfield. For the next six hours we had to laboriously tow the big boat we were in by using a small rowboat dinghy. It was kind of like two strokes forward, one stroke back trying to tow this big boat in this little dinghy. I thought it was a pretty hilarious situation. We were going into a slight wind to reach Madeline Island, where we would eventually spend the night and call the marina the next morning. During that towing experience in which Jim Harris and I each shared half hour shifts, the somewhat obsequious and even-handed Mr. Harris complained that I was exceeding my time, putting in more time than him! (laughter) And not evenly sharing the workload! I found that immensely funny, so much so that as I was laughing Jim became even more incensed when he saw that I was laughing at him complaining that I was doing too much work!

Neil: Oh, that’s good.

Sumner: Perhaps my state of mind reflected a certain giddiness after a long day at sea, and I could laugh at almost anything by that evening. Later, much later, Jim reflected on the situation and had a good laugh. We were the best of friends.

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