Lake Manitou appears exempt from new lake trout restrictions

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Lake Manitou appears exempt from new lake trout restrictions

 

 

March 11, 2009

Jim Moodie / manitoulin.ca

 

 

NORTHEAST ONTARIO-Regulatory changes are in the offing to reduce pressures on lake trout in the sprawling fishery zone that includes Manitoulin, but Lake Manitou anglers appear to be off the hook.

 

"I've made the case that Lake Manitou deserves special consideration," said Wayne Selinger, biologist with the Ministry of Natural Resources (MNR) in Espanola. "I've done an evaluation of Manitou and it's presently in fairly good shape for lake trout."

 

The same can't be said for other parts of Zone 10, the vast fisheries management area that extends from the French River in the southeast to as far north and west as Elk Lake and Wawa. Manitoulin was lumped into this zone last year and represents its southernmost precinct.

 

Between 2000 and 2005, the MNR conducted an assessment of lake trout across Northeastern Ontario, choosing 130 randomly selected lakes in the region that host the cold-water species, the bulk of which fell within Zone 10. And the results weren't promising.

 

"The bottom line is that only 32 percent of the trout lakes assessed were found to have a high abundance of the fish, and of these, nearly half were fished beyond an acceptable level," noted Mr. Selinger. "The report card for Zone 10 doesn't look encouraging, and something needs to be done to address that."

 

Lake Manitou, the Island's only lake to accommodate the species, makes for a dramatic exception to this general trend, however. "It's 10,000 hectares and far more productive," said Mr. Selinger. "It's kind of like a lake trout factory, would be one way to put it."

 

The big spring-fed lake benefits from warmer temperatures than the rest of the region, which translate into "higher growing degree days" for trout, said the biologist, as well as boasts a limestone base that "builds that further and drives lake trout growth and maturity."

 

All of the other lakes in the zone that support a lake trout fishery are in Canadian Shield country, and their concentrations of this popular sport fish aren't doing nearly so well. Sudbury lakes, in particular, are taking a big hit.

 

"The Sudbury area has the lowest quality lake trout lakes in Fisheries Management Zone 10," reads a fact sheet produced last month by the MNR. "Only 20 percent have good or healthy lake trout abundance and 53 percent are classified as degraded."

 

There are several reasons for this decline. "Acid damage is one factor, although many of these lakes are recovering," noted Mr. Selinger. "Obviously fishing pressure and harvest are part of it, as well as the spread of species like bass and rock bass that aren't typically a component of a lake-trout lake."

 

The introduction of bass generally occurs through "careless use of bait and unauthorized stocking," said Mr. Selinger. And about a quarter of the trout lakes in Zone 10 have now become colonized by bass species, according to the five-year study.

 

While some trout lakes can withstand the presence of such finny kin, others suffer from the competition, as bass gobble up a lot of the prey fish along the shore. "You can point to some lakes and say it hasn't made much difference, but it's kind of like Russian Roulette," said Mr. Selinger.

 

Other forces influencing the health of lake trout in the zone are water quality and climate change, noted the MNR biologist. "Lake trout like cold water, so if warming occurs they are going to get squeezed," he pointed out. "That's part of the need to act now, because these other things on the horizon will put even more pressure on the situation, so we have to cut back on angler take."

 

In looking at the information gathered by the MNR, members of the Zone 10 advisory council, which includes an Island representative, have recently agreed upon a series of management strategies to curb angler impact and preserve populations of this freshwater char, which is judged to be the second most popular sport fish in the zone.

 

Mr. Selinger wasn't in a position to discuss the specific recommendations, as their unveiling awaits an Environmental Bill of Rights (EBR) posting for public comment, although he allowed that strategies to deal with overharvest almost necessarily involve an adjustment to one (or all) of the following: limits, size restrictions and season dates.

 

The Expositor has independently obtained a draft of the changes that are apt to be put on the table, the most striking of which is a proposal to reduce the winter fishing period by over a month, with the opening date for trout fishing delayed until February 15. That would affect every lake in the zone save Lake Manitou, which has been recognized for its higher rate of productivity and would preserve its January 1-September 30 season.

 

The one change that could impact Island anglers is the daily limit, which could be reduced from three fish per day to two.

 

Another strategy being proposed is to maintain similar seasons for put-and-take fisheries to deflect fishing impact from lakes where naturally reproducing trout are more vulnerable.

 

Lake Manitou has a combination of planted and naturally occurring lake trout. "It's not a put-and-take lake," stressed Mr. Selinger. "It's both stocked and has strong natural recruitment, so we're just supplementing what's there."

 

The stocking of lake trout in Manitou is currently following a "two years on, two years off" cycle, said the biologist, "so that we can see what the natural year classes will be."

 

In general, though, Manitoulin's largest and deepest lake has proven itself to be a virtual hot house for the species. "They grow faster and mature younger there," said Mr. Selinger. "Across the zone, they will reach 40 centimetres at age seven. In Manitou, they're only two or three years old when they reach 40 centimetres, and are mature at age four."

 

He attributes this speedy growth largely to the limestone environment, which has "innate productivity." To make the argument for Manitou's exemption from the proposed changes to lake trout regulations, the biologist compared dissolved solids in this lake (a key measure of productivity) to those of other lakes. "Manitou has over double the amount of the next best lake in the zone," he said.

 

In a paper he prepared on the status of Lake Manitou, Mr. Selinger writes, "Based on the analysis of some key parameters known to drive lake trout productivity and population dynamics, Lake Manitou very clearly resides outside the bounds of the (Zone 10) data set."

 

While the recommendations concerning the trout fishery-including Manitou's exemption from significant changes-await public review and ministerial sanction, Mr. Selinger is confident that the unique nature of this inland lake will be reflected in any future decision.

 

Manitoulin as a whole has already, along with the French River, earned a distinction within the broader zone as "specially designated waters," meaning there is an existing recognition that exceptions should be made for this area when it comes to management strategies.

 

If there is a risk to Manitoulin's unusually bounteous resource, it would likely be an increase in visits from off-Island anglers who find the opportunities for lake trout fishing scaled back in other areas of the zone.