News Photo by Julie Riddle Fisherman Dale Sanderson and first mate Karen Schulte, on a boat in the Rogers City Marina on Thursday, demonstrate how big a Lake Huron salmon can grow.

ALPENA — If anglers find bigger salmon at the end of their hook, they can thank a rainbow smelt, according to a state fish biologist.

Salmon weighed in by anglers so far at this week’s Brown Trout Festival in Alpena show more heft than in recent years, with salmon catches on the leaderboard averaging 25.05 pounds as of Wednesday night, compared to leaderboard averages of 20 pounds or less for each of the past five years.

In Rogers City, fisherman Dale Sanderson hasn’t caught a salmon this year, but other anglers tell him this year’s chinooks are huge, he said at the city’s marina on Thursday.

The bigger the salmon, the more thrilling the catch, Sanderson said, describing epic battles involving reels and reels of fishline, bent rods, and strong-willed fighters on the end of the line.

“All of a sudden, when he starts taking your line out, and you’re holding on, you can’t believe a fish is that strong,” Sanderson said, saying that, in comparison, catching even a big lake trout is like pulling in a wet sweatshirt.

The bigger salmon ratcheting up the excitement for anglers this year reflect a slight uptick in the number of rainbow smelt — a forage fish similar to sardines — around northern Michigan, according to Tim Cwalinski, senior fisheries biologist for the Michigan Department of Natural Resources in Gaylord.

A few decades ago, anglers regularly hauled in 30-pound chinook salmon — also called king salmon — when the fish gorged themselves on the abundant alewife population that collapsed shortly after the start of the century, Cwalinski said.

Chinook, more than other kinds of salmon, rely heavily on alewife, said Cwalinski, comparing the fish to a person who “would eat peanut butter and jelly for breakfast, lunch, and dinner.”

With their food source depleted, the choosy chinook often showed up on hooks weighing in at eight or nine pounds, with 20-pounders uncommon for the past 20 years, the fisheries biologist said.

Though preferring alewives, salmon will nibble rainbow smelt. Decades ago, fishermen netted smelt by the gallons-full in northern Michigan rivers in spring, according to Cwalinski.

That fish, like alewives, suffered a population decline but appears to be making a slight resurgence, providing a slightly heartier supper for salmon, Cwalinski said.

“There’s just a few more peanut butter and jelly sandwiches running around out there than there used to be,” he said.

While chinook — which can grow to 129 pounds in their native Pacific Ocean — may grow larger locally than in recent decades, Lake Huron anglers shouldn’t expect every salmon to be a big haul.

Still, he said, anglers will keep hoping local salmon find hearty dinners before making their way to the end of a fishing line.

“Who doesn’t want to hook a 25-pound king that’s just ripping your arm off out in Lake Huron?” Cwalinski said.