The Fish Thief: How a Parasite Nearly Decimated the Great Lakes Fisheries

Imagine a fishery where, in one year, 6 million pounds of fish were hauled in—only to plummet to a mere 400 pounds just four years later. What caused this devastation? And who were the culprits?

What caused the great lakes fishery to collapse? / photo provided by Darby Communications

THE FISH THIEF - A Fishing "Whodunit"

Commercial fishermen are often the first to get the blame. After all, they’re the ones pulling millions of pounds of fish from the water. In the case of the Great Lakes in the 1940s and 50s, this same narrative unfolded. The lake trout population was nearly wiped out, and all fingers pointed at commercial fishermen. The problem? None of those fingers pointed in the right direction.

A fish packing plant from the 1940s in the Great Lakes area. / photo provided by Darby Communications

A Fishery Saved From the Brink

THE FISH THIEF: A Great Lakes Mystery is a documentary from SkyhoundMedia and the Great Lakes Fishery Commission that tells the story of an environmental crisis that nearly destroyed one of the world’s most treasured fisheries. It unravels a hidden catastrophe that impacted industries, communities, and livelihoods on both sides of the U.S.-Canada border.

Invasion of the Body Snatchers - Real Life

THE FISH THIEF recounts how the Great Lakes were brought to their knees by the sea lamprey, a parasitic invader that decimated the lake trout population. When I say decimated, it is with no stretch of the imagination. As already stated, when the yearly haul of lake trout is 6 million pounds and then 4 years later it is 400 pounds, that's a near wiping out of a whole population of fish.

Notice how skinny the lake trout is. The lamprey is sucking most of the nutrients out of the fish leaving it emaciated, weak, and with less chance of survival. / photo provided by Darby Communications

Complete and Thorough Story Telling

Thomas Lindsey Haskin, the film's director, tells the complete and true story of the devastation caused by the sea lamprey by combining historical footage, underwater video, and interviews with scientists, local community members, and commercial fishermen who experienced the disaster firsthand.

His use of scientific information with personal narratives makes the dire situation both informative and emotional.

A Fishery in Crisis

When an entire fishery collapses, so does everything connected to it. Families who for generations relied on fishing for their livelihood were left struggling. Indigenous communities, whose culture and traditions were deeply tied to fishing, were hit hard. The lakes, once pristine, became breeding grounds for slimy, eel-like parasites as long as your arm.

What a lamprey leaves behind when it is done with the fish. / photo provided by Darby Communications

The Devastation Was as Ugly as It Sounds

Imagine being a commercial fisherman, heading out to make a living, and finding your nets empty—or worse, what few fish were caught had lampreys hanging from their sides, or a gaping hole.

While the nets were empty the underwater floor wasn't, instead it was littered with dead fish that had the life sucked out of them from these parasites.

The Fight to Save the Great Lakes

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The crisis boiled down to three questions:

1. How did the sea lamprey invade the Great Lakes?
2. What is their natural history?
3. How do you get rid of them?
These questions became the focus of a relentless battle to save the lakes and restore balance to the ecosystem. The Fish Thief tells the story of this battle in vivid detail, highlighting the resilience of the people and communities determined to reclaim their waters.

photo provided by Darby Communications

THE FISH THIEF: A Great Lakes Mystery is set to release in the U.S. and Canada on January 31, 2025, it will be available to stream, download, or rent on platforms including Apple TV/iTunes, Amazon, Google/YouTube, and Tubi. It is an eye-opening doc and worth a look. KB

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"The gods do not deduct from man’s allotted span the hours spent in fishing.” - Herbert Hoover

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