The fish had been in the lakes long before people developed roads, cities, and dams. Some fish can live for more than 100 years and return year after year to breeding grounds.
However, for some Michigan fish, this trip has been blocked for over 100 years. The Black River now contains barriers that did not exist when lake sturgeon first established their migration routes.
They block migration routes the fish once used naturally.
As discussions about the dams enter a new stage, one question becomes important.
What do conservation groups think is necessary to connect these ancient fish to their original migration route?
Migration stopped more than a century ago
Lake sturgeon are among the oldest fish species in North America. Their ancestors date back more than 100 million years. Size and longevity make the fish unique compared to almost all other freshwater fish in the Great Lakes.
However, they depend on rivers remaining open during their migration. For generations, the Tower Dam and Kleber Dam have blocked fish migration on Michigan’s Black River.
Before the dams were constructed, the fish were able to travel upstream to their breeding areas.
Under the reservoirs of both dams lie two former waterfalls.
Lake sturgeon often spawn near waterfalls and rapid water flow.
Therefore, these submerged waterfalls help show what the river was like before the dams were built.
The discussion is entering a critical stage
Both hydroelectric dams are undergoing FERC relicensing, creating an opportunity to consider how the river will operate in the future. The Black River discussion is unfolding alongside a broader effort to reconnect fish habitat across northern Michigan.
Supported by NOAA Fisheries funding, the Grand Traverse Band of Ottawa & Chippewa Indians is completing fish passage restoration work. The work involves removing twelve road-stream barriers and restoring about sixty miles of streams. Although smaller than the dams, greater attention is now being focused on large obstructions on the Black River.
Lake sturgeon typically spend decades developing before reproducing.
Opening migration routes could affect populations for multiple generations.
Long-term restoration efforts have already helped increase lake sturgeon populations in northern Michigan, according to research from Michigan State University.
Michigan Department of Environment, Great Lakes, and Energy (via Facebook) notes that lake sturgeon are making a comeback in Michigan waters after years of conservation and restoration efforts.
Removing the dams is one proposed solution
This restoration project accomplishes far more than simply connecting smaller streams. It also includes studies examining potential fish-passage designs at Tower and Kleber dams. The goal is to identify ways lake sturgeon may again have access to upstream habitats.
Members of the Grand Traverse Band and partner organizations have indicated support for removing the dams entirely during relicensing.
They view removal as a way to reopen sections of the river that have been closed off for more than a century.
It would also allow access to historic spawning sites.
The decision could shape the river for generations
Work completed thus far builds on numerous years of lake sturgeon recovery throughout Michigan. Long-term restoration activities in Black Lake have shown that conservation efforts can produce lasting improvements. Those gains occur when fish are capable of completing more of their life cycles.
To researchers and tribal leaders, reconnecting rivers is about more than helping a single species. They view lake sturgeon as a sign of healthy rivers; therefore, restoration efforts for them will likely assist many other native fish.
For more than a century, the fish have been unable to reach parts of the river that were once part of their migration.
Whether those barriers remain standing or are removed will affect future generations of one of the oldest fish in the Great Lakes.
In some rivers, conservationists are trying a different approach by helping migrating fish move past dams instead of removing the barriers.
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