DULUTH — Fish populations in Lake Superior and its surrounding fisheries are faring much better than expected a year after a major storm dumped up to 10 inches of rain in the Duluth area and sent tons of sediment rushing into the big lake and its surrounding rivers and streams.
"I'd say the Lake Superior fishery was little affected," said Don Schreiner, Department of Natural Resources area fisheries supervisor for Lake Superior. "Fishing this spring has been gangbusters. Lots of lake trout and coho and chinook salmon are being caught."
The North Shore's trout streams also survived but were permanently rearranged. Schreiner said some young fish died last year, but he doesn't expect long-term impacts.
University of Minnesota Duluth's Large Lakes Observatory chemistry professor Elizabeth Minor told the Star Tribune (http://bit.ly/12yit49) the lake appears to be resilient, but the jury is still out on the long-term impact.
Yet, so far, researchers say it appears fish mostly weathered the floodwaters, the infusion of sediment and even the rearranging of stream beds.
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The impact to the St. Louis River estuary, a popular fishery filled with floodwaters carrying trees and sediment, is more uncertain, but is also showing positive signs. Officials say 1,500 tons of rock placed below the Fond du Lac dam in 2009 to provide sturgeon-spawning habitat withstood the brunt of the flooding — and sturgeon and walleyes used the area to spawn this spring.
A DNR spring fishery survey also showed good numbers of walleyes.
"We didn't see a major issue there," said Deserae Hendrickson, DNR area fisheries supervisor. "One thing we definitely noticed was an increased amount of woody habitat in the water, which is a positive thing."
The trees, partly buried in sediment, provide fish habitat.
The event itself killed some fish, including some that were stranded in backwaters after the floodwaters subsided. "We did rescue some sturgeon and other fish," Hendrickson said, "but we couldn't get them all. But I can't say we saw a lot of dead fish."
Fish reproduction likely wasn't strong last year because of the flood, but Hendrickson said it will take a year or two to assess the impact.
