On Friday morning before last year's Saturday walleye opener, a long line waited impatiently outside River Rat Bait in Cohasset. For the next several hours, a near-constant procession of anglers funneled through the popular shop.

"We opened at 8 a.m. and closed at 1 a.m., and I can't remember a time where we weren't busy," said owner Ken Roy. "It's impossible to explain how out of hand it was — and we had eight people working at least part of the time. It was nearly nonstop. It was like a Black Friday sale. And the vast majority of anglers were here for one thing."

That one thing: spottail shiners, the unrivaled minnow of choice for fishing the many walleye lakes in north-central and parts of northern Minnesota.

But this spring, as the May 12 opener draws near, the prospects of a spottail shiner shortage are very real, say minnow trappers, wholesale dealers, fishing guides and bait shop owners. While other live bait (fathead minnows, leeches, etc.) should be easier to come by, late ice-out on many lakes in the region — similar to conditions in 2013 — have trappers sitting on the sidelines waiting for open water and the annual spawning run of spottails. A dearth of the coveted minnows for the opener would impact thousands of anglers and the bottom lines of many in the fishing industry, including minnow trappers and bait shop owners.

"Right now it's going to be close," Jonny Petrowske of Waskish said of the availability of spottail shiners. "It's a situation where we're going to find out a few days before the opener. I do know one thing: Supply is going to be very, very small because of the late ice."

Petrowske is a fourth-generation minnow trapper and guide who fishes Upper Red Lake primarily. He said the demand for spottails — the Cadillac of minnows, as some call them — is becoming a cultural phenomenon.

"They have an almost cult-like following," Petrowske said. "They do work really well for the first three or four weeks of the season, but for some they've taken on this exaggerated importance."

The spottail spawning run typically "happens a few days after ice-out" on select lakes, like Upper Red and Leech. Petrowske traps only one lake. He says he's like a factory that sells to wholesalers who in turn sell to bait shops. Meeting spottail demand in recent years, he said, has become harder because of evasive-species trapping restrictions. This year, late ice-out will cut into his profit margins and require him and his crew to do "two weeks of work" in a few days.

"It's become a cutthroat, nasty business in a lot of ways," said Petrowske, who monitors his trap sites with solar-powered cameras and uses chains and padlocks on his traps to keep competitors from stealing his stash.

"We're seeing too much illegal activity," he said.

Spottail shiners typically sell for roughly twice as much as fathead minnows, which are more common. Bait shop owners say anglers will hopscotch from shop to shop until they find what they need. Some will wait hours until minnow trucks arrive. If supplies are low, bait shops often feel compelled to ration what they have and spread the wealth to more anglers.

"I've been yelled at on more than one occasion when supplies are low," said Sherree Wicktor, owner of S&W Bait in Brainerd, who estimates 80 percent of her business the "first three or four weeks" of the season comes directly from spottail sales. "It's not like we can go to a store and order them. Spottail shiners come from the wild and they're weather-dependant. We can't guarantee anything."

Roy of River Rat Bait said 40 to 50 percent of his annual gross revenue comes from spottail sales. In general, bait shop owners say this year's price will hinge on what wholesalers charge them. Still, Roy said, high prices don't seem to faze too many anglers.

"I had one woman last year tell me she'd pay 10 times the amount I was charging for a pint of spottails," he said. "It's gotten that crazy."

Meanwhile, Ross Hagemeister, a fishing guide from Battle Lake, said recent warm weather has him hopeful that ice-out will happen before the opener.

"A week or so ago I was ready to get the rope out," said Hagemeister, laughing. "But the weather has changed and I'm confident we'll have open water, though I'm not confident about the availability of spottail shiners, especially for bait dealers.

"There's a reason everybody is clamoring for them early in the season: because they work really well," added Hagemeister. "There's something about a spottail shiner that in most cases they [walleyes[ won't take anything else."

Tori J. McCormick is a freelance writer living in Prior Lake. Reach him at torimccormick33@gmail.com.