August 2, 2012 at 1:00 am

Invasive species alter nature of sports fishery

Talia Hare, right, 7, of Chesaning, poses with the 17-inch walleye she caught with S.W.A.T (S.almon W.alleye A.nd T.rout) Charter Service owner and captain Jerry Rankey of Munger. (Todd McInturf / The Detroit News)

For much of the past 25 years, Jerry Rankey has loved to watch the fight: grown men hooking into Chinook "king" salmon out on the waters of Lake Huron and battling back and forth until the fish have landed or escaped.

Such battles are fewer and farther between on Lake Huron these days as fishermen charter boat captains like Rankey, and biologists will attest. Lake Huron's fishery has been completely reshuffled by a variety of factors — most notably, invasive species — creating an angling environment that is worse to some, better to others but different from what everyone remembers just 10 years ago.

"The lake has been greatly altered by invasive species and the food web has been flipped upside down," said Brandon Schroeder, an educator with Michigan Sea Grant, whose mission today is convincing anglers of Lake Huron's new fishery. "But the lake is now a place where you can go and fill your catch with five different kinds of fish — all of which you'd be happy to catch."

The change is largely due to the invasive zebra and quagga mussels, according to biologists. Small fish, like alewives, that once served as food for the Chinook have disappeared because of the mussels. And when the food fish became scarce, so did the prized salmon.

At first, officials with Michigan's Department of Natural Resources attempted to combat the loss of the prized Chinook with stocking efforts, but that proved ineffective. The agency decided to play the cards it had been dealt.

"We have to manage these fisheries regardless of what is out there — whether it's native species or new invasive species," said Todd Grischke, Lake Huron Basin Coordinator for Michigan's Department of Natural Resources.

"The reality is we're managers of the resource that's there. So the more invasives that show up and modify that environment, the more difficult our job becomes. The main point is let's keep them out, so we don't have to deal with them."

Number of anglers down

For decades, anglers traveled from all over the country to do battle with a Chinook. That influx put money in local wallets up and down Lake Huron's shoreline. From charter operations to local hotels to bait shops, the salmon were a major draw.

Now that the large numbers are gone, the impact is being felt all the way down the line.

Greg Sundin, the city manager in Alpena, said the decline of the Chinook has been felt in the past seven years.

"We've certainly seen it in our fishing tournaments — changes in the numbers of participants," he said. "It affects the total number of people who come to the city. Those people often stay a full week. And they're buying food and doing other things while they're here."

Earlier this month, 23 boats were signed up for the city's Michigan Brown Trout Festival, a super tournament that targets the largest fish like Chinook.

"Ten years ago there would have been over 100," said Don Gilmet, the city's harbor master, who cites the loss of the salmon as one of the reasons the municipal port has fewer boats in its slips.

The overall decline in Lake Huron fishery harvest has been significant, according to the U.S. Army Corps of Engineers. In 2000, the lake produced $7.6 million worth of fish. By 2009, that number had shrunk to $4.8 million.

A chain reaction

The invasives — most often arriving in the ballast water of commercial shipping vessels — have been accumulating in Lake Huron for decades. By 2003, the combined impacts of the zebra and quagga mussels started a chain reaction.

By consuming all of the nutrients available near shore, the mussels were eliminating the food source for alewives — a major food fish for salmon. Other species that might have served as a replacement food source for the Chinook, such as lake herring or Cisco, were dwindling as well from habitat loss, over-fishing and water quality issues.

In 2000, Chinook made up 58 percent of the fish caught for recreation in Lake Huron. A decade later, that number was 8 percent, according to the DNR.

In spite of the decrease in salmon, other species have thrived.

In the old ecosystem, the prevalence of alewives served as a detriment to the proliferation of fish like walleye and trout in Lake Huron. The steady diet of alewives broke down the thiamine in female trout, resulting in eggs that did not hatch.

As the number of alewives dropped, higher reproduction rates were recorded among steelhead and other species. In 2000, less than 2 percent of the fish caught for recreation in Lake Huron were walleye.

In 2010, walleye made up 49 percent of the total haul. They are doing so well, DNR officials have stopped stocking them to maintain their numbers.

The invasive round goby, meanwhile, which often have taken over fish environments, have become a food source that has helped bolster the populations of smallmouth bass and other species in Lake Huron.

For those with the fond memories of the Chinook's heyday, it's not easy to let go.

These days, Rankey's charter trips bring in plenty of walleye and perch. And when people ask him the best place to go for salmon, he tells them to try the west side of the state.

"It's a different environment on Lake Huron now than it used to be," Grischke said. "If we can promote the positives, it would help us move forward and away from what we used to be."

jlynch@detnews.com

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