As a native of the Washington, DC area and relative urban and suburban life, until recently, my depth of familiarity with maritime life, resources and economies was truly slim. I will be honest in having a hazy understanding of the word fishery, hatchery, or what was meant when mentioning the work of fish management. While my knowledge is still not deep, I have learned much more through my Great Lakes exploration of the past three years.

Here is the mission of the Fish and Aquatic Conservation program of the U.S. Fish and Wildlife Service: We are committed to tackling the nation’s highest priority aquatic conservation and recreational challenges to conserve, restore, and enhance fisheries for future generations.

My lack of clarity around the word fishery is actually understandable. The word is used in a number of different, and sometimes inconsistent, ways. According to Wikipedia, Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place (a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish farms, both in freshwater water bodies (about 10% of all catch) and the oceans (about 90%).

Last post I shared about the infamous, massive alewife die-off of 1967 in Lake Michigan waters and shores. I ended with the question: What did they do about it?

In this case the “they” ends up being the Michigan Department of Conservation. And what they did was initiate one of the largest bioengineering endeavors of all time. States around the Great Lakes agreed to introduce coho and Chinook salmon from the Pacific Ocean into the lakes to bring the alewife population under control. It was a successful effort to redesign the Great Lakes fishery. Alewives were back to more controlled numbers by 1971.

Introducing salmon was the brainchild of Dr. Howard Tanner. In The Life and Death of the Great Lakes, Dan Egan writes a riveting chapter about Tanner – his environmental management expertise, his love for Michigan and the Great Lakes, his vision, and his streak of independent decision-making fostered by his time as a soldier in World War II.

As head of the Michigan Department of Conservation, he led the effort to introduce salmon in 1966. Biologists had already recognized the overpopulation of alewives by that time. Just one year later, by the fall of 1967, millions of salmon offspring appeared in Lake Michigan. The salmon grew large and heavy on the alewife diet. It created a frenzy of recreational fishing. Egan describes it memorably: “It was as if all the skiers in Michigan awoke one morning to find that their little hills had been replaced by the Rocky Mountains.” Recreational fishermen who had dreamed of one day fishing out West for salmon literally found them leaping out of the waters of Lake Michigan. Word spread of “coho fever”. Beyond successfully controlling the alewife population, the effort created a recreational boom in sport fishing and a new constituency of people invested in the Great Lakes. 

The Great Lakes have been known as a world class salmon fishery ever since. However, some danger signs have been flashing over the past thirty years. Nature constantly brings our attention back to cycles and interconnectedness – and sometimes seems to enjoy a little irony on the side. The alewife population is now dwindling.  And in dwindling, it may take the salmon with it given that they rely almost exclusively on alewives as their diet. That much despised little silver fish has been revisited, recognized, and respected for its role in the Great Lakes fishery.

In early July 2022 we drove to Northern Michigan to drop our older daughter off at summer camp for two weeks. For the weekend we stayed at a house about 25 miles east of Ludington. My husband and I drove up into Ludington State Park on the shores of Lake Michigan. As we drove in, gorgeous white sand dunes lined the road. It was early evening, so a transition time with beachgoers emerging from trails through the dunes, colorful umbrellas, chairs and towels in hand, headed back to their cars.

We parked and got out of the car to walk out on the beach. We were immediately greeted by what I can only describe as, frankly, a strong, unpleasant odor. Putrid is too strong a word, but it was fishy, and rotten. We walked over a dune path and emerged on the beach. The view was incredibly picturesque – gorgeous wide white sand beach and cottonball clouds. But a quick stroll closer to the water revealed the source of the smell – there was a band of dead, washed up small, silver fish stretching down the beach in both directions.  

These fish are alewives, and wash-up like this is, somewhat unfortunately, not an uncommon occurrence on the shores of some Great Lakes. The history of the issue is well-explained in Dan Egan’s book The Death and Life of the Great Lakes that I refer to time and time again. It’s a story of ecological imbalance.

River herring are a species well known to east coast North Americans for centuries. They hatch in the rivers flowing into the Atlantic and then head into saltwater for much of their life before heading back to the freshwater to spawn. 

River herring were first found in Lake Ontario in the late 1800s. It’s unknown how they got there – whether they made their way on their own through the St. Lawrence River or accessed it through the canals dug at the end of that century. For several decades they lived in some ecological balance as the Atlantic salmon and lake trout were natural predators. But once the evolving commercial fishing industry ramped up and overfishing of salmon and trout became an issue, the river herring became massively overpopulated. By 1931 they had been found in Lake Erie and by 1954 in the waters of all Great Lakes. 

The Great Lakes river herring quickly evolved to be a smaller, toothless version of the East Coast river herring. They lacked natural predators, and quickly came to dominate the fish mass of the lakes, especially Lake Michigan, where by 1965 they were likely 90 percent of the lake’s fish mass. By this point they had also come to take on another name – alewives. 

My dad was living in Chicago in the summer of 1967 when the city experienced the most infamous alewife happening of all time. There was essentially a massive die-off of alewives that dumped billions of fish carcasses on the shores of Lake Michigan around Chicago. 30 miles of shoreline were “smothered”, as Egan writes, by piles of decaying fish sometimes shin deep. The cost of management and clean-up in Chicago was pegged at $50 million – $350 million in 2017 dollars. The price tag across the entire summer and all the shores impacted: close to $1 billion in 2017 dollars. 

To most people, the die off was seen, and smelled, along the shore. However, in the water, there were reports of piles of carcasses at the bottom of the lake over 6 feet high and live schools of the fish were so thick that boaters described running into one being like running into a snowbank.

What happened?  

The reason turns out to be to be biological maladaptation. The fact that the alewives, originally saltwater fish, were able to live in the freshwaters of the Great Lakes didn’t mean that they were able to thrive. Their bodies simply didn’t work well due to the lack of salt. They experienced kidney stress, stunted thyroid activity, and an inability to handle the dramatic water temperature changes the Great Lakes can experience. But their mere survival had thrown Lake Michigan completely off-balance with no real predators to keep the population in check.

So what did they do about it? Stay tuned for Part 2 of the story in my next post. 

Photo from Whiting Robertsdale Historical Society

We’re going to pause from our Great Lakes tour for a post or two. Right after the new year, a number of you sent me this article from the Washington Post – or others on the same topic. The Great Lakes were in the news.

January 1st, 2024 recorded the smallest amount of ice cover over the Great Lakes in the past 50 years. Only 0.35% of the lakes’ surface area was under ice. The lakes average 9% for New Year’s Day. There is clear evidence of a downward trend likely due to climate change. Between 1973 and 2017, the lakes recorded as many as 46 fewer days per season frozen, which is defined as days when at least 5% of the lakes’ surface had ice cover.

There is variability year to year – 2019 was one of the highest ice coverage years on record (81% coverage at one point!), and things can also change through a season. Highest ice coverage is usually seen in February and early March.  

Why does this matter? The National Atmospheric and Oceanic Administration (NOAA) has provided a helpful answer.

There are several challenges to note. Thick ice protects the shoreline from erosion and flooding during winter storms. Animal patterns are disrupted, including those of fish who use ice for protection during their spawning season. Some areas of the Great Lakes have developed winter recreational seasons for things like ice fishing that depend on ice coverage.

But one of the main impacts of this shift for those living in the region is an increase in the well-known lake effect snow phenomenon. Lake effect snow occurs when cold air, often a front from Canada, sweeps across the relatively warmer waters of the Great Lakes. As it moves, warmth and moisture from the lake water rises into the lowest portion of the atmosphere. Because it is warmer and less dense than the cold air, it rises and creates clouds and snow.

Unfrozen lake is a prerequisite for lake effect snow. So, with less ice coverage at the start of January, the region was ripe for the impacts of lake effect snow, and we saw it in the middle of the month when a frigid front came through and we saw substantial snowfall.

For those of us living in the region, there is high variability with how lake effect snow is experienced. It can sometimes bring a light, innocuous, low density snow. But it can also bring strong bands of dense snow that can appear quickly, at times causing dangerous conditions for driving. Climate change and warmer temperatures will likely exacerbate the extremes causing punishing snows like those Buffalo experienced in the closing days of 2022 when between 50 and 77 inches of snow fell around the region.

In sum, climate change is driving a deep irony for the Great Lakes region. Warmer temperatures are moderating the climate overall, but increasing some of the most extreme winter weather that drives stereotypes and boastful declarations about the superior liveability of places like Florida and the Sunbelt. I encourage you to think critically about this sentiment though. Winters here can have some extremes but summers there have some extremes – and in some places dwindling access to freshwater. There is nowhere to escape our warming planet. We all have burdens to bear in the short and long-term. 

And, as I shared in one of my earliest posts about retreating from life on Lake Erie in the winter of 2021, the snow and ice can be mighty beautiful.