The pollution concerns around the Great Lakes are many, ranging from forever chemicals such as PFAS to legacy pollution, industrial accidents, and oil spills.
Some very popular birds are making a comeback, but because of one toxic pollutant, they’re not doing as well as they could be.
Trumpeter swans are the biggest waterfowl in North America. They’re huge compared to Canada geese. They’re all white with a black bill. Their call — as one writer put it — is something like a badly tuned trumpet.
These trumpeter swans have been restored to the Great Lakes region in just the last few decades. They had been hunted until they were wiped out in the Great Lakes region by the end of the 19th century.
In 1960, there were only 3,700 trumpeter swans in all of North America and most of those were in Alaska, with a few in Canada.
These days, it’s not uncommon to occasionally spot a pair of trumpeter swans on lakes and ponds throughout the region.
In Michigan, one guy did a lot to bring them back.
A New York Times article from 1987 describes Joe Johnson flying back from a zoo that had trumpeter swans. On the plane, he had a box of eggs in the seat next to him. He kept taking a hot water bottle back to the lavatory to fill it up in order to keep the eggs warm.
We talked with Johnson in 2000 while watching a couple of pairs of trumpeter swans at the Michigan State University Kellogg Biological Station. Johnson worked there for decades.
He was pretty thrilled about the return of the swans, but at the same time, he talked about the hazards they face.
“The population is growing at about 17 percent per year despite the losses to lead poisoning, vandalistic and accidental shootings, high-tension wires. They’re doing great.”
Joe Johnson is no longer with us. He passed away in 2012, but he and colleagues in the Great Lakes and other Midwestern states as well as in Canada have quite a legacy. From that population in 1960 of fewer than four thousand trumpeters, there are more than 63,000, according to the most recent survey in 2015.
But, as it was 24 years ago, that lead poisoning Johnson mentioned is still a problem.
“You can see the hook right here in the mouth or near the bill. There is a swivel snap right here in the gizzard,” said Julie Melotti, a wildlife pathologist with the Michigan Department of Natural Resources.
She was pointing at a digital x-ray of a dead trumpeter swan.
“And then, do you see this big bright oval shape? That would be a lead sinker.”
Melotti said when they have bird livers analyzed for lead, 20 parts per million is considered toxic.
“This bird was 141 parts per million. So, high, high levels of lead in this bird,” she noted.
Trumpeter swans are not the only birds being poisoned by lead.
“With fishing tackle, we might see that in loons, more than any of the other waterbirds,” Melotti said.
Loons are diving birds. They swim to find things on the bottom of a lake or pond. Sometimes what they find is not food.
“An angler loses fishing tackle or it's not recovered and it's a piece of lead. And they're shiny and they're bright objects. And (the loons) might grab those or pick them up at the bottom of the water.”
It’s not just lost fishing tackle that’s killing waterfowl. Melotti showed me an image of a duck that had ingested a single small pellet from a shotgun shell. It died from lead poisoning.
The George H.W. Bush administration banned lead shot for waterfowl in 1991. Lead pellet-filled shotgun shells can still be used for other types of hunting.
Even though hunters cannot use lead for hunting ducks and geese now, there’s still lead in wetland areas where hunters gathered in the past. Shotguns have been around for a long time, longer than the U.S. has been a nation. Depending on the size of the shotgun shell, the number of lead pellets can range from fewer than 200 to more than 400. You can imagine decade after decade of duck hunting in the same spot means some places are lead hot spots.
“Some of these wetlands where maybe they were near a Sportsman's Club and clay shot was shot over. Those are more of your legacy sources that we've had, areas that we've recovered swans from,” Melotti explained.
She said several years ago she and a colleague found more than 800 pellets in the gizzard of a swan.
“That's a lot of lead. One swan. One bird. We actually dug and counted every single one of those pellets out of that bird.”
Shotgun pellets are not the only source of lead. Many bullets are lead or partially lead. That causes another problem.
The American bald eagle is seen as a noble bird, but in a letter to his daughter, even Benjamin Franklin questioned its nobility. He wrote that the bald eagle was a bird of bad moral character, not getting his living honestly because it steals fish from other birds. The eagle also is a scavenger.
Anyone who spends a fair amount of time in the Northwoods region has probably seen an eagle by a roadside, eating a dead deer carcass that was hit by a car. They’ll also take advantage of a dead deer shot by a hunter, but not successfully tracked down. They’ll also eat from the internal organs and guts from a deer that’s been field dressed and left on the ground.
Melotti said the bullets often splinter into fragments and can be easily swallowed by the bird.
"A lot of people don't know that eagles are scavengers, and they think of these beautiful, majestic birds and they don't think of them as is eating off of carcasses," she said. "And so, I think just that the knowledge that these birds are getting poisoned by lead is important to share, so that hunters and anglers can make informed decisions when they choose their ammunition or choose their tackle and look for nontoxic alternatives.”
A colleague of Melotti’s, a Wildlife Disease Ecologist at Cornell University, Krysten Schuler, noted that lead ammunition proponents say "eagles have recovered; they’ve been taken off the endangered species list." That’s true, but that’s because the pesticide DDT was taken off the market. DDT made eggshells thin and reproduction rates for eagles and other birds of prey plummeted. Schuler said that doesn’t mean lead is not suppressing the eagle population.
“We did an analysis of over 1,200 records from seven different states in the northeast U.S. And what we were able to find was, yes, lead had an impact on the population. It didn’t stop the population recovery, but it was just like kind of keeping your foot on the brake as you’re trying to drive forward. The population recovery wasn’t as expedient as it could have been, but it didn’t stop it.”
A study released in 2020 found 1,490 eagles were killed in Michigan between 1986 and 2017. The study, published in the Journal of Wildlife Management, found nearly 12 percent of the bald eagles were killed by lead poisoning. That’s 176 eagles.
Schuler said she’s a deer hunter, and hunter education teaches you to have one target. So, if your kill causes other animals to die, such as raptors, that’s a problem.
Another issue hits closer to home.
“There’s also the element of human health in that a lot of people don’t understand that these lead bullet fragments are microscopic and they can travel a pretty considerable distance from the wound channels. So even if you’re cutting a lot of the meat out, you could still be exposing your family or friend or whoever you’re sharing that venison with to lead unintentionally,” Schuler said.
During the last day of the Barack Obama administration, the Interior Secretary put a policy in motion to phase out the use of lead in any kind of ammunition for hunting and phase out lead in fishing tackle.
One day into the Donald Trump administration that policy was struck down.
Some conservation hunting and angling groups have said there’s no evidence that the use of lead has had significant impacts on wildlife. The National Rifle Association said at the time that lead ammo was under attack by anti-hunting groups whose ultimate goal is to ban hunting.
But some hunters think ending the use of lead is about being a real conservationist.
Drew YoungeDyke writes for outdoor magazines and online sites. He uses copper ammunition when he’s hunting. We visited him as he was about to fly-fish in the Huron River. He ties his own flies and instead of using lead in those lures, he uses tungsten.
“I personally don’t use any lead in my own fishing. And what I found is, I don’t need it to catch fish,” he said.
He’s an ambassador for a group called Sporting Lead-Free. It’s a nonprofit group of hunters and anglers spreading the word about substitutes for lead.
“Trying to talk to our peers and help them understand that it does have impacts on birds like bald eagles, like loons, that share the environment with us that we hunt and fish.”
YoungDyke went to the river’s edge and started casting, but something went wrong.
“Well, I was drifting a nymph, a tungsten weighted nymph. The idea of a nymph is to kind of tickle along the bottom. Sometimes it snags rocks, it bumps logs. It comes off, it comes loose. Sometimes you don't tie it well enough and you lose a fly as I just did. You never tie a fly thinking you're going to lose it. You never buy a lure thinking you're going to lose it. But anglers are imperfect people and sometimes we lose them," he said. "And as much as it pains me to have spent the time I did to tie that fly, I'm at least reassured that wherever that fly ends up, it's not going to poison a loon, and it's not going to poison an eagle.”
YoungeDyke said some hunters and anglers just don’t realize how toxic lead can be to wildlife. Some just don’t want to switch because they’ve always used lead and it’s cheaper. For others, they just don’t want anybody telling them what they should or shouldn’t do.
Climate change and northern winters
During the winter, there are fewer kinds of birds around the Great Lakes because many species fly south.
But the ones that stick around are iconic: ravens, blue jays, cardinals, and bald eagles.
Even people in the Great Lakes region who don’t think about birds all that much, will often mention the comeback of the American bald eagle. That’s because if they get outdoors, it’s likely they’ve seen the big birds when they almost never did a few decades ago.
Eagles prey on smaller birds, and mammals, although they seem to like fish best. In the winter, the inland lakes and some rivers freeze. But that freeze doesn’t last as long these days. This past winter, the Great Lakes region was much warmer than usual.
At the University of Michigan Biological Station in the far northern part of the state’s Lower Peninsula, researchers keep track of the snowpack. Karin Rand led me out to a large field to show me a new sonic rangefinder. It takes really accurate measurements of the amount of snow on the ground.
“The data we’ve been getting off of it is every half hour that it measures the snow depth.”
There was a big snow early in the year of about two feet at the station. Usually in early February, there’s still an average of 16 inches of snow. Not this year.
“Basically, since then — and that was in mid-January — we have been just slowly declining all the way to what we have now, which is like maybe two inches of packed wet snow on the ground.”
Rand said to her it was sad to see how little snowpack was on the ground in early February.
So, what’s the big deal? Well, it might be an indicator of how winters will look in the future in the upper Great Lakes region. That is likely to cause chaos in the timing of how nature works.
Aimée Classen is the Director of the Biological Station. She said a slowly melting snow pack regulates the amount and timing of minerals and nutrients that are carried into the creeks, rivers, and lakes. Too little in the way of nutrients, or nutrients that arrive too soon, might affect the aquatic organisms that rely on them.
“Normally when we have rain, it moves nutrients from our landscapes into aquatic systems, it’s during the summertime. So, all the organisms that live in those aquatic systems can take up those nutrients and it gets retained. But, in the wintertime, if those aquatic systems aren’t active, then it just gets washed out of the watershed.”
That means the nutrients that would feed the plant organisms that kickstart the bottom of the food web each year could come too early. That could ultimately affect fish — and eagles.
But not everything in those streams is completely reliant on those new nutrients.
A couple of decades ago, volunteers took me to a remote creek. Rochelle Breitenbach and Mary Bajcz were going to search for stonefly larvae.
Adult stoneflies make good fish food. And fish are a mainstay for kingfishers, herons, egrets and more. But those insects are really susceptible to pollution. If there are lots of stonefly nymphs, Breitenbach told me that’s a good indication a stream is healthy.
“Their food source is on decomposing leaves, so that’s where you find them. And then, I will get some of the leaf packs in the net and then I’ll dump it in the tray.”
So, these insects are not as reliant on the timing of nutrient releases upstream.
One of the coordinators at the Huron River Watershed Council said that doesn’t mean they’re not affected by climate disruption.
“In many cases, climate change amplifies existing stressors,” said watershed planner, Daniel Brown. He’s also a climatologist who’s worked with Mass Audubon in Massachusetts.
“Climate change gets things out of sync. So if you have, you know, say fish spawning or insects emerge two weeks earlier, but, birds migrating have started their migration journey three or four weeks earlier, they can get out of sync with their critical food sources along their migration route. So you've fundamentally disrupted the ecosystem and the interdependencies throughout that ecosystem. So that has all kinds of cascading effects.”
What that all means is the amount of snow pack and the increasing intensity and frequency of heavy rainstorms that have come with a changing climate all have an impact on the amount of nutrients getting into streams and lakes. If there’s not enough nutrients, there are fewer aquatic organisms. And even if the nutrients are enough but the timing of their release is off, that means less food for the fish. Fewer fish means less food for birds such as herons, egrets, eagles, and ospreys, not to mention people.
The chemicals birds are exposed to can end up on our dinner plates
Besides the changing climate, birds are also affected by pollution.
One of the questions researchers have been asking is whether pollution is actually being taken up by birds? A researcher at Cornell University, David Dayan, found that there were several kinds of toxic chemicals in the breast meat of ducks.
“We were looking at ones that were most likely to be actually consumed, because not as many people eat those fish-eating birds, or they're advised not to use those fishing birds as much,” Dayan said.
That’s because we already know fish are contaminated. That’s been thoroughly studied. Each time a fish-eating duck, such as a merganser, eats a fish, the contaminants build up in their flesh.
Many studies have looked at those more contaminated waterfowl, but Dayan took a different approach.
“We ended up with five species that are most likely to be hunted and then consumed by hunters. So they were mallard, black duck, green winged teal, wood duck, and Canada geese.”
He and his colleagues looked for legacy pollutants such as mercury, dioxins, and polychlorinated biphenyls (PCBs). But they also looked for emerging contaminants such as PFAS.
“First and foremost, there is just a diversity of chemicals present in these muscle tissues. We looked for 40 PFAS; we found 25 of them. We looked for 20 organo-chlorines; we found 21 of them. PCBs were detected in every single sample. But at varying ranges. So just as a first step, we found very diverse chemicals across all of these species," Dayan said.
Birds pick up the pollutants different ways. They eat water bugs and other invertebrates in the water, they pick through the sediment where some of the chemicals settle, and it’s simply in the water itself, some places worse than others. Many of those chemicals accumulate in the ducks.
And duck and geese hunters are just beginning to learn that the food they’ve put on the family table for decades might be contributing to health problems. Dayan said “might,” because unlike fish, waterfowl consumption hasn’t been studied that thoroughly.
The pollutants we’ve been talking about so far are just a few of the many that are affecting waterbirds. There are those mercury, dioxins, PCBs we mentioned. But there is also DDT in some watersheds, as well as a whole alphabet of toxic chemicals. There are pharmaceuticals that are messing with the reproductive development of amphibians and fish, things that some ducks, herons, kingfishers, ospreys, and eagles eat.
The Environmental Working Group found at least 330 species of wildlife have been contaminated by PFAS.
Some water sources are so badly polluted that signs have been posted along rivers warning people not to eat the fish. But birds cannot read those signs.
The rather sudden discovery of PFAS in the water in a lot of places after it had been there for decades also begs the question: what other chemicals are in the water that we just haven’t tested for yet?
Beyond that, no one fully understands what these chemicals do when they’re mixed together in our streams and lakes. Do the compounds cause increased toxicity? There are just too many chemicals that could mix too many ways to know.
The answers are more restrictions on chemicals getting into the water in the first place. But that would cost corporations money. And it would cost government agencies that operate wastewater treatment plants more. That cost would be passed on to customers at a time when society is already struggling with water affordability.
In the end, we end up paying that cost either in dollars or in higher health care costs and greater losses of wildlife such as birds.
Microplastics in the water, in birds, in us
Another pollutant is getting an increasing amount of attention, and for good reason, it’s everywhere, microplastics.
These are tiny bits of plastic fragments — plastic waste that breaks down into little pieces. Or it could be fibers from our clothing that come out in the wash and get swept down the drain. They’re too tiny for wastewater treatment plants to capture them. Microplastic fibers can even travel through the air.
These fibers and microscopic pieces get into rivers and lakes. A study from the Rochester Institute of Technology found 22 million pounds of plastic from the U.S. and Canada get into the Great Lakes each year.
The problem is insects and fish can ingest these fibers and fragments. And even teeny tiny phytoplankton in the water can take in microplastics.
“Even in these really, really tiny organisms, they can ingest these small microplastics. And it is possible for trophic transfer to occur and transfer these to higher trophic level organisms,” said Madeleine Milne. She’s a grad student at the University of Manitoba who studies microplastics in wildlife and the food web.
As bigger and bigger creatures eat smaller things like insects or fish, the microplastics get moved up the food web.
Scientists have found microplastics in the digestive systems of birds.
Tham Hoang is an associate professor at Auburn University. He collaborated on a study with Father Stephen Mitten, a Jesuit priest who teaches classes about birds at Loyola University. They looked at six bird species.
“And we found that pretty much every sample we looked into, we found microplastics in their digestive systems,” Hoang said.
But they don’t know what that means for the birds, yet.
“There’s been a lot of macroplastic research in birds, particularly shorebirds, because many (times) mortality is due to digesting these huge piles of plastic, which keeps them from being able to digest other foods,” Mitten said.
They agreed that more research into the possible health effects needs to be done — and that includes questions like: are the chemicals in the plastic affecting the birds?
But Stephen Mitten said it matters for us, too.
“We can go back to the canary in the coal mine. Birds are indicators of ecological health, and if birds are affected by pollutants and plastics and microplastics and other chemicals in the environment, so are we. So it’s a wake-up call for human health.”
And scientists have found microplastics in bottled water, beer, and food at the grocery store.
“We were finding microplastics in fish straight from fishing vessels, as well as fish filets being sold in grocery stores. There definitely is microplastic contamination present but it was quite low in those foods. We found higher contamination in products that were more highly processed, like fish sticks and chicken nuggets. Things like that had a lot more contamination than our more minimally processed products like chicken breasts, pork loins and fish filets,” said Madeleine Milne.
Scientists have even found microplastics are in our bodies. They’ve been found in our blood, our lungs, our hearts, in placentas, and as was just recently reported on NPR, in testicles. But, just like in birds, we don’t know yet what that might mean for our health.
Oil spills
There’s one other big pollution concern. In 2010 an Enbridge oil pipeline burst and about a million gallons of oil in the Kalamazoo River had be be cleaned up. Some birds were killed.
Enbridge has another pipeline that concerns many people. The more than 70-year-old Line 5 sits on the lake bed of the Straits of Mackinac, which connects Lake Michigan and Lake Huron. If that pipeline under the water were to release oil because it burst or was damaged, it’s uncertain how much of the coastline would be affected and how many birds could die.
Enbridge has proposed putting Line 5 in an underground tunnel. Enbridge officials have said that would make a “safe pipeline even safer.” That plan is working its way through government agencies to get the required permits.
Some Michigan government officials and many of the state’s citizens don’t want that either. They simply want Line 5 in Michigan to be shut down.
The Bird Connection was written and produced by the Environment Report’s Lester Graham and Rebecca Williams. Vincent Duffy was the editor. The program was made possible by a grant from the Charles Stewart Mott Foundation. This was a production of Michigan Public in partnership with the Great Lakes News Collaborative.
