Home » Device from 234 B.C. lifts fish over barriers while blocking invaders, study finds

Device from 234 B.C. lifts fish over barriers while blocking invaders, study finds

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The U.S. Geological Survey watches from a boat as the Archimedes screw is installed.Image: Scott Meals

Elaine Maron

In 11 days, a device dating back to 234 B.C. successfully transported 704 fish across the Cheboygan Dam in the northern Lower Peninsula of Michigan. study found.

Archimedes screws are a promising solution for lifting fish over low-profile barriers such as concrete blocks into optical sorters, according to Daniel Zielinski, principal investigator at the Great Lakes Fisheries Commission in Traverse City.

The aim is to prevent the upstream migration of an invasive species known as sea lamprey.

The eel-like sea lamprey, with its large round mouth and sharply curved teeth, preys on native fish such as lake trout and whitefish in all five Great Lakes.

The commission says 433 streams and tributaries in the Great Lakes are known to produce sea lampreys.

Applying lamprey repellent TFM to kill sea lamprey larvae is the primary method to control them.

However, strategic barriers have also been put in place to prevent sea lamprey spawning. Experts have turned to manual trap-and-sort systems, which have been viewed as time-consuming and detrimental to the health of native fish.

But a new device that uses the same technology as the iPhone for facial recognition can identify fish species with 95% accuracy. Moreover, he can distinguish between sea lampreys and other species with 99% accuracy.

While the new technology has proven successful in separating fish, Zielinski said there was also a need to test a device that could effectively transport fish over barriers.

“The Archimedes screw is a fairly rudimentary tool that can lift water very easily,” says Zielinksi. “You can lift anything in that water. They’re actually used in Europe and the Southwest as fish-friendly hydroelectric systems.”

Also known as a water screw, the device is named after the ancient Greek inventor and astronomer Archimedes.

A fish lift installed in the Cheboy Gundam.Image: Scott Meals

An Archimedean screw has at least one blade around a central axis, surrounded by an outer cylinder that may be fixed or rotated. According to the study, “While the screw rotates, water and fish are caught in the bucket and carried upstream.”

A prototype fish lift was tested at a dam about 1.5 miles upstream from where the Cheboygan River empties into Lake Huron.

This experiment demonstrated that “a mixture of migratory Great Lakes fish
transported safely, with no observed injuries or deaths,” the study said.

Zielinski said the Great Lakes Recovery Action Plan calls for the removal of river barriers, but that could be problematic.

“When we start removing these barriers to improve the migration of native species, there are unintended consequences for invasive species, which lead to other problems,” Zielinski said.

“Having a tool that can selectively let fish pass through will be very important, not only because we need to restore conductivity for desirable species, but because we need to control invasive species.”

Needless to say, the dam created a drinking water supply.

Study co-author Scott Meals of the U.S. Geological Survey, an expert on fish migration behavior, said traditional reliance on fish ladders to overcome barriers in the Great Lakes is not effective for most fish. said no.

“Our fish can’t do that,” says Meals, who is based at the Hammond Bay Biological Station in Millersburg, Michigan.

“When people think of fish ladders, they think of West Coast salmon jumping up the stairs to clear around hydroelectric dams. A fish that jumps isn’t really a great jumper,” he said.

Archimedes’ screw carried these suckers safely to the Cheboygan Dam: Image: Scott Meals.

According to Meels, fisheries managers have been facing catch-22 for a long time.

“They have the challenge of stopping the spread of invasive species. This requires barriers, but at the same time reintroducing fish and connecting Great Lakes tributaries to the lakes themselves to keep migratory fish species from spreading. We need to open up habitats or something,” Meers said.

“We’re trying to provide a tool that managers can use to block fish with these barriers, while still allowing some degree of conductivity with native species,” he said.

Zielinksi says hydraulics are important when it comes to the ability of fish to move upstream.

Zielinski said. “It should let the fish know that this is an alternative route upstream. is.”

Funded through the US Fish and Wildlife Service and the US Geological Survey Rapid Response Grant, the Cheboygan River project cost $40,000.

According to Miehls, the project was simply a proof of concept. Now, the team is using another $58,000 in funding to create a separate unit further downstream to see what effect it has on which fish enter the imager. They plan to break ground in spring 2023.

The study was published in the journal Water.

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