It was bad enough that alewives in Lake Ontario were making it difficult to restore the Atlantic salmon for which the Salmon River is named.
Now, it appears the alewives have caused trouble for the river’s steelhead trout, too.
Scientists from government agencies and Cornell University are still trying to figure out why so many steelhead in the Salmon River died during the fall run. One theory that seems to be getting some traction is that alewives proved to be an especially unhealthy diet for steelhead in the lake this summer.
The herring-like alewife, native to the East Coast, is thought to have been accidentally introduced to the Great Lakes in the early 1800s, when the Erie Canal connected Lake Ontario to the Atlantic Ocean.
They flourished — to the point where Great Lakes states decided to introduce Chinook and coho salmon, native to the Pacific Ocean, to the lakes to keep the alewives in check.
Alewives produce an enzyme called thiaminase, which causes bigger fish that eat them to be deficient in thiamine, better known as vitamin B1. The problem isn’t serious in Chinook salmon, but it’s very serious for Atlantic salmon.
The abundance of alewives in Lake Ontario is thought to be a big reason why efforts to repopulate the lake with Atlantics have been largely unsuccessful.
Steelhead have eaten Lake Ontario’s alewives with few ill effects ever since they, too, were introduced to the Great Lakes. But this year’s crop of alewifes may have been extra toxic, according to Steve LaPan, the Department of Environmental Conservation’s Great Lakes section head.
When they’re stressed, alewives produce more thiaminase. The bitterly cold winter of 2013-2014 left them very stressed indeed, LaPan said.
“The alewifes in the fall of 2013 went into the winter in excellent body condition,” LaPan said. “This past spring, their body condition dropped dramatically. It was nowhere near a record low, but they definitely had come into the spring stressed from the winter, and when they’re stressed, they produce more of the enzyme” that causes vitamin B1 deficiency.
Even so, there are plenty of healthy steelhead in the river for the winter fishing season, said Paul Conklin of East Greenbush, owner of Paul’s Guide Service in Pulaski.
“Even with the current situation with the steelhead on the Salmon River, there is no shortage of fish to be caught from top to bottom in the river,” Conklin said.
Author John Gierach will make his debut at the 23rd Fly Fishing Show in Somerset, N.J., on Jan. 23-25.
Gierach will be at the show’s author’s booth at 3:30 p.m. Friday and Saturday and 1:30 Sunday. Other big-name authors slated for Somerset include Lefty Kreh, Bob Clouser and Mike Valla of Ballston Spa, whose new book, “Tying the Founding Flies,” will be published Jan. 15.
The book is a companion to Valla’s 2013 book “The Founding Flies,” which covers 43 classic American patterns and the people who invented them. Valla has quickly become the premier historian of what the late writer Gordon Wickstrom called, in a glowing review of “The Founding Flies,” “that most excellent of objects: the trout fly.”
Capital Region fly-tiers Pat Cohen of Cobleskill, Jay “Fishy” Fullum of Ravena and Bill Newcomb of Hillsdale will be at their vises, demonstrating their craft. As always, there will be scores of outfitters, artists and fly shops, including the Gloversville-based The Fly Shack.
The Fly Fishing Show will be at the Garden State Convention Center. Show hours are 10 a.m.-6 p.m. Friday, 8:30 a.m.-5:30 p.m. Saturday and 9 a.m.-4:30 p.m. Sunday. The International Fly Fishing Film Festival will be screened Friday at 6:30 p.m.
Tickets are $18 for one day, $28 for two days and $38 for all three. More information is at flyfishingshow.com.