Lake sturgeon continue recovery in Rainy River and Lake of the Woods
A recent lake sturgeon population study in Lake of the Woods and the Rainy River illustrates the slow, steady sturgeon population recovery owing to cleaner water, effective fishing regulations and vigilant enforcement -- a success story that one ...
A recent lake sturgeon population study in Lake of the Woods and the Rainy River illustrates the slow, steady sturgeon population recovery owing to cleaner water, effective fishing regulations and vigilant enforcement - a success story that one day will allow anglers the realistic expectation of catching 100-pound sturgeon.
“This strategy has worked very well,” said Henry Drewes, northwest region fisheries manager with the Minnesota Department of Natural Resources. “The fact that the lake sturgeon population has continued to expand in numbers, as well as in size and age distribution, under ever-increasing angling pressure is credit to those who worked together to bring about this recovery.”
The population study assessed and estimated the number of lake sturgeon longer than 40 inches, part of an effort to gain more information and a better understanding of lake sturgeon status, population dynamics and movement patterns. Sturgeon longer than 40 inches can be sampled with confidence using available gear, and at that size the fish are approaching sexual maturity.
There are an estimated 92,000 lake sturgeon longer than 40 inches in the system, which compares to an estimated 59,000 fish in 2004 and 17,000 in 1989.
“This is another high point in a continuing recovery success story,” said Phil Talmage, Baudette area fisheries supervisor with the DNR. “Results of the latest study show there’s a greater number of large lake sturgeon in the population than in 2004, when a similar study was conducted.”
In mid-April, 2014, in cooperation with the Ontario Ministry of Natural Resources offices in Kenora, Fort Frances and Thunder Bay and the Rainy River First Nations, DNR fisheries biologists from Baudette and International Falls began setting nets to capture and tag lake sturgeon. The study area included spawning sites on tributaries, all 82 river-miles of the Rainy River below the International Falls dam, Fourmile Bay, and a large portion of Big Traverse Bay on Lake of the Woods.
From June through mid-September, biologists used gill nets to recapture sturgeon at randomly selected sites on the southeastern portion of Lake of the Woods, and the entire length of the Rainy River.
“This was a very ambitious project given the size of the study area, the nomadic nature of lake sturgeon and the sheer number of fish required to make a statistically valid estimate,” Talmage said. “We are extremely pleased with the results of this effort.”
Anglers who were fishing for lake sturgeon in the study area during the tagging phase helped by allowing biologists to tag sturgeon they caught. With angler help, DNR biologists tagged 1,291 lake sturgeon longer than 40 inches, then used that count and data obtained from the recapture efforts to estimate the total population at 92,000.
“We appreciate the cooperation from anglers who allowed DNR staff in boats to tag and release their fish,” Talmage said. “These folks were a valuable part of our research efforts.”
Successful recovery means more angling opportunities
The outlook for lake sturgeon hasn’t always been so positive. Over-harvest through the late 1800s and early 1900s decimated the lake sturgeon population in Lake of the Woods and the Rainy River. Despite reduced harvest, poor water quality played a major role in limiting sturgeon recovery.
Water-quality improvements directly linked to clean water regulations beginning in the 1960s set the stage for restoration of this unique fishery. Better water quality in the Rainy River initiated a dramatic response in lake sturgeon reproduction and survival, which became the basis for population recovery.
“The recovery of the Rainy River is one of the best examples of how clean water regulation positively influenced angler opportunities in Minnesota,” Drewes said. “This is truly a unique opportunity that continues to improve for anglers.”
Based on the research findings and the success of the recovery program, lake sturgeon populations should remain strong and anglers can expect more opportunities to catch larger fish in the future.
“One day, in the not so distant future, lake sturgeon in the 100-pound class will become a realistic expectation for lake sturgeon anglers,” Drewes said.