Lake sturgeon populations in both the United States and Canadian waters of Lake of the Woods and Rainy River have met short-term recovery goals, and fisheries managers now are setting their sights on the long term.

"The Rainy River-Lake of the Woods population is probably one of the most robust, healthiest recovering populations of lake sturgeon in North America," said Tom Mosindy, fisheries assessment biologist for the Ontario Ministry of Natural Resources in Kenora, Ont. "It's definitely a good news story."

Mosindy is chairman of the Border Waters Sturgeon Management Committee, which includes representatives from the MNR, the Minnesota Department of Natural Resources and the Rainy River First Nations Indian band in Ontario. He shared findings of the recovering sturgeon population with partners last week during a joint Ontario-Minnesota fisheries meeting in Fort Frances, Ont.

Sturgeon populations on Lake of the Woods and Rainy River were nearly wiped out in the early 1900s as a result of overfishing and declining water quality in the river where the sturgeon spawn. Mosindy said he attributes the turnaround to clean water legislation enacted in the late '60s and early '70s in the United States and Ontario.

"As soon as water quality improvements occurred, the sturgeon responded to them overnight, and we started seeing regular successful reproduction and spawning," Mosindy said. "And the population has continued to do that all the way through."

A look at the goals
The short-term recovery goals called for male sturgeon to age 30 and females to age 50, with fish larger than 70 inches present and 30 year-classes, or fish from a given year's hatch, in the population.
Regular assessment work confirms the short-term goals have been met.
"We're there, which is a great accomplishment," said Phil Talmage, area fisheries supervisor for the DNR in Baudette, Minn. "The recovery has been sustained."
Fisheries managers say they will continue to work toward long-term goals, which include male sturgeon to age 40 and females to age 70, with 10 percent to 15 percent of the population consisting of fish longer than 80 inches. There also would be 40 year-classes of sturgeon in the population under the long-term guidelines.
"Our goal is to get there, but when you look at the age and sizes and information we have now, this is going to be years off," Talmage said. "Once we reach that, we will have arrived at a population that has reached our expectations."
Sturgeon can live more than 100 years and exceed 200 pounds. They're also late bloomers, so to speak; sturgeon don't reach sexual maturity until their late teens to mid-20s, and male sturgeon spawn only every two to three years.
"We don't have enough data on female fish to come up with concrete numbers on how often they're spawning, but literature suggests every four to nine years," Talmage said.

More work ahead
Mosindy said the MNR and Minnesota are planning some intensive assessment work over the next few years to better understand the Lake of the Woods population. He said the sampling and management strategies Minnesota and Ontario have used to achieve sturgeon goals could help fisheries managers elsewhere develop recovery plans.

"There's a lot of focus now on recovery plans for endangered species," Mosindy said. "And sturgeon are right at the top of the list."
Mosindy said he also hopes the partners can develop a new population estimate for sturgeon in Lake of the Woods and Rainy River. As part of the last estimate in 2004, fisheries crews tagged about 700 sturgeon and then launched an intensive recapture effort a couple of months later. By comparing the ratio of tagged to untagged fish, Mosindy said, the partners were able to develop a population estimate of about 50,000 sturgeon that were either adults or sub-adult fish approaching 40 inches in length.

He said the previous estimate in the late '80s and early '90s put the population at about 15,000 sturgeon in Lake of the Woods and Rainy River.
That means numbers of basically tripled within 15 years.
"It's an unbelievable population recovery within that amount of time," Mosindy said.
Off-limits in Ontario

While Minnesota allows angling and a limited harvest on lake sturgeon in Lake of the Woods and Rainy River, the species has been off-limits in Ontario waters since 2009. The reason, Mosindy said, is Ontario's Endangered Species Act, which classifies sturgeon in three broad geographical regions. The species is doing well in Lake of the Woods and Rainy River, but that's not the case elsewhere in northwestern Ontario, the region in which the fishery falls.

Mosindy said the Ontario designations someday could be broken into smaller geographical units that could allow fishing to resume on the Canadian side of Lake of the Woods and Rainy River, but no such action is imminent.

Sturgeon fishing continues to gain popularity in Minnesota waters, the DNR's Talmage said. That's despite regulations restricting anglers to one sturgeon per year by permit only and extensive periods when fishing is limited to catch-and-release. The season closes completely from mid-May until July 1.

"A lot of people come up here just to catch and release lake sturgeon," Talmage said. "Minimizing the harvest while the fishery is recovering has allowed that recovery to continue.

"There's a lot to be learned from this population."