Indices of a modified smelt-ouananiche cycle at Lac Saint-Jean

Observations and key indicators tend to show that the smelt-landlocked historic cycle, which caused significant fluctuations in the success of fishing on Lake Saint-Jean, is a thing of the past.
The figures for the 2019 run at the Mistassini River Fishway, which has been used as a base since the early 1970s, are the first sign of a change in the cycle. As of Monday morning, 713 fish were counted by technicians, for an average projection of 848 fish.

This means that at least 1251 spawners will move up the Ashuapmushuan, 449 the Salmon River and 477 the Métabetchouane River. This number is particularly high, considering the quality of the fishing season observed so far.

“The fishermen have had very good success right from the start in the Val-Jalbert and Chambord sectors. The landlocked salmon has not stopped biting since. We could have had a less abundant run in terms of numbers, but we are increasing compared to last year, “says biologist and director of the Lac-Saint-Jean Fishing LACtivity Corporation (CLAP), Marc Archer.

Preliminary

Not everything is cast in concrete, however. Science is based on evidence and for the moment, observations are preliminary. It will take a few more years to be able to conclude with greater certainty on the success of the solutions put in place to try to cut off the prey-predator cycle.

“We all know that the limiting factor for landlocked salmon in Lac-Saint-Jean is the availability of smelt stocks when smolts arrive in the lake. The 25 stone islands that we built at the Mistassini River, in the Île aux Pins area, are now three years old, “says the biologist.

He goes on to explain that “the egg sensors placed in 2018 and 2019 confirm that the islets are used by smelt. It takes another year of observations to demonstrate with certainty that these structures play their role well. ”

The other clue that leads the CLAP executive director to rejoice is the state of stone islands. Spring freshet carries large volumes of sand into the Mistassini River. There was therefore a significant risk of silting islands in the spring, but verifications made using a submersible camera confirm that the islets are in the same state as their construction.

The current portrait of landlocked salmon in Lac-Saint-Jean encourages the director of CLAP to raise new questions about the scientific model developed over the years to arrive at a more precise management of stocks. Among the tools, the scientific committee used the early spring opening of the fishery, the increase of the quota of two to three salmon per day per fisherman and the fly fishing in the river.

“Our management model, which targeted 300 to 500 landlocked salmon at the Mistassini fishway, was established prior to the establishment of 25 stone blocks to help improve the success of smelt spawning. It is possible that our management target is no longer adapted to the new situation, “continues Marc Archer.

The director of CLAP does not hide that there is a second phase of islets in the plans. Another network of 25 structures is planned in order to make additional gains for hatching smelt eggs, and thus increase stocks for landlocked salmon.

In addition to being the staple food for landlocked salmon, smelt is also part of walleye feeding. Actions taken to support salmon would also have benefits for walleye, which is just as popular with fishermen because of the quality of its flesh.

University of Quebec Chicoutimi Chair (UQAC), Pascal Sirois, concedes that there are, at this time, “happy coincidences” in the ecosystem of the landlocked salmon of the lake Saint John, which does not, however, provide scientific conclusions on the potential success of this 20-year project.

The biologist, who has been leading the research since the end of sowing, recalls that the basic idea was to eliminate stock falls and arrive at an average fishery with years of superior abundance. This abundance usually translates into fishing success.

“It makes several happy coincidences,” says Pascal Sirois, “when the fishing success and the numbers on the returns are submitted to him. We can not draw a conclusion. It will take several years of data to get there. ”

Pascal Sirois opted for a historical reminder that the paradigms have changed in Lac-Saint-Jean.

From now on, all stakeholders agree that the limiting factor was energy availability for salmon (smelt).

“It accentuated the problems when sowing was stopped. With the cessation of seeding, the natural prey-predator cycle was gradually restored. For three years now, actions have been taken to increase smelt stocks with the facilities to improve the success of smelt spawning, “recounts the UQAC professor.

The researcher can not advance a percentage of spawning improvement.

However, once the eggs are more likely to survive, there is an increase in stocks: “At least 95% of the smelt eggs that fall on the sand will die. If you increase the rate to 10 or 15% survival, it’s already a good difference. ”

In the specific case of Lac Saint-Jean, millions of smelts have to be used to build stocks to support the smolts that run down the rivers.

With regard to the ideal management model, which reported 300 to 500 spawners in the Mistassini River fishway, Pascal Sirois considers that it will be time to analyze this assessment.

It considers it necessary to check these models every ten years to take account of new realities.

The biologist does not reject the idea of ​​extending the network of rock structures to increase the success of smelt spawning.

The research carried out on the biological characteristics of Lake Saint-Jean confirmed the capacity of the water body to support much larger stocks of landlocked salmon.

In the immediate future, the Director of the Chair will discuss with the Lac-Saint-Jean Fishing Corporation the follow-up to be given to the 57-page scientific article which established that Lake Saint-Jean is considered a world jewel for landlocked salmon.

The professor would like a wide dissemination of the article translated into French or a summary of the scientific article, which would allow the population to understand the importance of this scientific communication.

The Mistassini River Fishway has been used as a base for observations since the early 1970s.
The Mistassini River Fishway has been used as a base for observations since the early 1970s.
THE DAILY, LOUIS TREMBLAY
Big catches

Many fishermen report catching ouananiches of 15, 16 and 17 inches. These are landlocked salmon that have spent a year in the lake after the downstream migration. Their large numbers in the catches confirm that they have access to abundant food. The abundance of salmon of this size suggests another good fishing season next year as they will still benefit from smelt stocks unless there is an uncontrollable natural event.

Less permits

In recent years, the Quebec government has observed a decrease in the sale of licenses for hunting and fishing activities. The CLAP Lac-Saint-Jean also notes this disaffection, despite the quality of fishing. The organization recorded a decline in fishing effort and daily access sales after the record walleye season in 2012. According to its director, Marc Archer, the fishermen of landlocked salmon, because of the success, maintain the fishing effort right now.

The popular fly fishing

The popularity of fly fishing in the river is no longer deceiving. For this season, anglers had the opportunity to book two days on three rivers where this activity is practiced, instead of three days, as was the case until 2018. CLAP made this decision to allow more fly fishermen have access to this activity. Fishing trips are awarded during the winter after a draw. More and more fans are signing up for this annual draw

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