Mysterious blue perch surface in Minnesota

From: http://www.twincities.com/mld/twincities/sports/outdoors/14117606.htm

BY CHRIS NISKANEN
Pioneer Press

Minnesota already lays claim to a mythical blue creature, Babe the Blue Ox.

Now, it can claim a new and puzzling scientific oddity, one sure to be the buzz at bait shops: the blue perch.

Since December, Minnesota ice anglers have landed at least four yellow perch, a common panfish species, that aren't yellow at all. These are bright blue with an iridescent glow. Startled anglers who have caught the mysterious fish have been sent scrambling to the Internet or the Department of Natural Resources for answers.

The trail eventually leads them to Dr. Wayne Schaefer, a University of Wisconsin-Washington County professor who has been studying blue-hued walleyes in a remote region of Canada since 2000.

Until this winter, Schaefer hadn't heard of blue perch in Minnesota. But he believes they share the same color variation as the Ontario blue walleyes. The blue perch are likely albino for yellow pigment — the key color element in their skin — and they have skin mucus containing a newly discovered blue protein.

Two blue perch were caught in Lake Mille Lacs this winter. Another came from Lake Winnibigoshish, and another came from Big Lake in Beltrami County, said Schaefer.

He operates a Web site, www.bluewalleye.com, where anglers are reporting their unusual catches.

Nothing about the blue coloring makes the perch unsafe to eat, nor do they have any contaminants, Schaefer said. The blue coloring isn't an apparent mutation, either, because their DNA resembles normal yellow-colored walleyes and perch.

"The blue walleyes are coming from the cleanest waters in Canada,'' said Schaefer, whose school is in West Bend, Wis. "It's not because of an environmental toxin, but it could be a response to an environmental change, such as more ultraviolet radiation hitting the Earth."

AS BLUE AS BLUE CAN GET

Whatever the case, Dick Bassing of Andover was startled when he pulled up a blue perch from Lake Mille Lacs on Dec. 18.

"When I first saw it, the silverish part of it really shown; it was really iridescent,'' he said. "But when I got it on the ice, it looked silverish and bluish." Three weeks later, the son of one of Bassing's friends, Mitch Stone, caught a slightly smaller but identical blue perch.

"How ironic is that?'' marveled Bassing. "Here I catch what is a once-in-a-lifetime fish, and someone else I know catches one, too. It really burst my bubble."

Gerald Albert, the DNR's fisheries biologist for Lake Winnibigoshish in Grand Rapids, also examined a large blue perch caught from the lake by a father and his two sons this winter.

Albert, who didn't recall the anglers' names, sent photos to Schaefer, who is coincidentally one of Albert's friends and occasional fishing partner.

"It was as blue as blue can get,'' Albert said of the fish. "I took some slime scrapings from the fish and sent them to Wayne, along with some pictures."

It was the first blue perch Albert has seen around Grand Rapids, where he has worked since 1989. He has netted and sampled thousands of yellow perch for DNR surveys.

"It would appear that the odds of catching one are really millions to 1,'' he said.

MYSTERY CONTINUES

The blue perch in Minnesota equally mystifies Schaefer, but he said similar fish have been reported in Wisconsin and Iowa.

He didn't rule out the possibility blue perch have always existed and are coming to light because of the Internet. But he does find the reports unusual, because until recently, most reports about blue-hued fish came from Canada.

For the past six years, Schaefer has been studying blue walleyes from waters near the towns of Ears Falls and Armstrong, Ontario. The blue walleyes, reported since the early 1900s, share the same lack of yellow pigment and unusual blue mucus.

Researchers hoped the Canadian walleyes were remnants of an extinct population of blue walleyes from Lake Erie, which disappeared in the 1950s. But genetic tests proved otherwise, Schaefer said.

However, their blue mucus is just as rare. The protein that causes it has never before been identified in nature, Schaefer said. "It seems like it is becoming more prevalent, and it's showing up farther south since I found it six years ago,'' he said.

Schaefer said he has recently discovered a small amount of blue pigment on many of the Lake Winnibigoshish yellow perch he has caught.

"I think it could be something quite important that we don't understand yet,'' he said. "Since it appears on the dorsal (back) areas of the fish, it could have some protective significance,'' he said. "But what's the source? We're trying to find that out."

Albert said the DNR doesn't have any plans to study the blue perch.

Bassing said he's having his blue perch mounted in special glass cases, along with two other normal perch he caught that day.

"The odds of catching a blue perch are like getting struck by lightning," Bassing said. "Since I've also been struck by lightning, I guess I really defy the odds."