North Shore tributaries to Lake Superior have been too cold this month to coax the annual steelhead run, but fisheries managers this week saw a sign that the spawning push is nigh.
On Monday at Knife River, 41 steelhead were swimming in the Department of Natural Resources fish trap 18 miles north of Duluth. Nick Peterson, the agency's migratory fish specialist, said the finding marked the first meaningful stream activity of the season.
"Males are usually the first to arrive and that's what was in there,'' he said. "We had a small push over the weekend.''
For the trend to continue, flows must remain strong and water temperatures need to climb a few digits to around 40 degrees. Every time this spring that stream water temps started to warm, they crashed from onsets of snow and cold rain, said Cory Goldsworthy, area fisheries supervisor for DNR. He will be watching this week to see if plunging overnight air temperatures will continue to have a chilling effect.
"Normally by now we'd be hot and heavy into the run,'' Goldsworthy said.
The two biologists said there is still room for a normal season. A year ago at this time, you could cross-country ski over some North Shore streams. But despite last winter's late thaw, steelheaders recorded an estimated spring catch of 3,200 fish — more than the historic shorewide average of 2,800.
"The fish still showed up, but they showed up at a different time,'' Peterson said. "That's kind of what we hope for this year.''
The widely anticipated annual season for the exceptional rainbow trout is dictated by river conditions as the fish seek a return to upstream spawning grounds. The migration requires strong flows of warming water — a combination that can be short-lived depending on the North Shore's snowpack and other factors.