The discovery of spawning whitefish in the Detroit River is evidence of the continuing recovery of a once heavily polluted and much abused waterway, federal wildlife authorities say.
Fisheries scientists from the U.S. Geological Survey and U.S. Fish & Wildlife Service last fall verified the presence of both spawning lake whitefish and fertilized whitefish eggs, the agencies announced Friday. It is the first documented spawning of the species, a key indicator species of ecosystem health, in the river since 1916.
"The return of the lake whitefish to the Detroit River is partially the result of 40 years of pollution prevention and control in the Detroit/Windsor metropolitan areas," stated Leon Carl, director of the USGS Great Lakes Science Center in Ann Arbor.
The whitefish is the top commercial species in the Great Lakes and is excellent table fare. But massive engineering in 1907 in the river, which connects and drains Lake St. Clair into Lake Erie, improved the channel for shipping but wrecked critical aquatic habitat. Along with pollution, those shipping works, loss of wetlands, invasive species, and overfishing ended the whitefish game in the river - until now.
Since 1972, the year of the U.S. Clear Water Act and U.S.-Canada Great Lakes Water Quality Agreement, discharges of oil have been reduced by 98 percent and phosphorus discharges by 95 percent. Mercury contamination in fish has declined by 70 percent and the PCB levels in herring gulls on the river's Fighting Island have dropped 83 percent, the federal agencies said.
"Scientists are continuing studies of this unique river ecosystem to learn more about the habitat needs of the lake whitefish and other native fish that may potentially lead to the re-establishment of this heritage fishery," summed Carl.
John Hartig, manager of the Detroit International Wildlife Refuge, the only international wildlife refuge in North America, said that the whitefish recovery helps draw attention to the river and refuge. The refuge includes islands, coastal wetlands, marshes, shoals and waterfront along 48 miles of the Detroit River and western Lake Erie.
"They'll probably move into Lake Erie and move into the eastern basin," said Hartig of the river's whitefish spawners. Whitefish prefer cool waters and in summer Erie's western basin typically grows far too warm for their comfort zone.
Whitefish eggs and larvae collected since last fall were taken to the federal Science Center and are being reared in the laboratory there.
It should not surprise western Lake Erie sport anglers to occasionally take a whitefish in early to mid-spring, before waters warm up significantly. Angler Bill Powers Sr., for example, took a 6-pound, 12-ounce whitefish on a Sonar blade bait while fishing for walleye in Maumee Bay on April 21.
But don't expect a booming whitefish sport fishery to develop, for the species just does not lend itself to common hook-and-line tactics. "They go for small baits and people typically don't use baits that small," said Jeff Tyson, research supervisor for Ohio's Lake Erie Fisheries Station at Sandusky.
Whitefish, he added, have small mouths and feed mostly on "mudbugs" on the bottom. "You won't typically catch them on shiners. When I have caught them, it has been on microjigs."
Tyson said whitefish typically move to the western basin in the fall, spend the winter here, and head east in April.
The fine spring fishing, the current rainy then windy spell aside, apparently is boosting sales of fishing licenses in the Buckeye State, for the Ohio Division of Wildlife reports resident annual license purchases are up 10.6 percent through April. The license-year began March 1.
In addition, nonresident annual license sales are up 14.7 percent, three-day tourist fishing license sales are up 23.4 percent, and one-day licenses are up 31.3 percent.
"It's still early in the 2006 fishing season but these numbers are very encouraging," said Steve Gray, state wildlife chief. "It's been better than we thought it would be."
Cooperative weather has been a factor, the division said.
Ohio hunters checked in 18,262 bearded wild turkeys during the month-long season that ended Sunday, the Ohio Division of Wildlife said yesterday.
The bag was up four percent from 2005, but well under a forecast bag of 20,000 to 25,000, possibly because the last 10 days of the season were battered by rains and wind in many areas.
Ashtabula County led the state with 782 birds taken, followed by Guernsey, 661; Harrison, 625; Meigs, 612, and Tuscarawas, 570. Another 1,872 birds were taken in the statewide youth hunting weekend April 22 and 23.
Top counties in the bag in northwest Ohio included Williams, 176; Defiance, 147; Huron, 130; Seneca, 100, and Paulding, 69. Lucas County registered 28 birds bagged and Wood County 14.