After three years of preparation, the Corporation de LACtivité Pêche Lac-Saint-Jean (CLAP) has started the development of 21 new spawning areas for the rainbow stint in Lac Saint-Jean. This species is the preferred prey of landlocked salmon.
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“It took us three years of preparation to start Phase 2 of the creation of smelt spawning grounds in the lake,” explained CLAP Director General Marc Archer. This work was scheduled to take place last winter but had to be postponed as the lake’s water level was higher due to work by Rio Tinto. The water under the ice prevented us from using machines on the site where we had to do the work. The area we are currently working in is extremely dry at this time of year. This shift also resulted in a 23% increase in the cost required from the contractor to more than $40,000. »
Photo provided by CLAP
To get to the site, a road had to be built on the ice of Lac Saint-Jean.
The sector affected by the work is regularly used by smelt for reproduction, but the bottom of the lake is essentially sandy and unfavorable for the survival of the eggs. Smelt remains the favorite dish of landlocked salmon living in Lac Saint-Jean. This species is the symbol of the region.
BETTER REPRODUCTION
Artificial spawning sites have already been shown to increase egg survival and natural melt production.
“Our goal is to provide landlocked salmon with more food. This will make it possible to stabilize the production of the species in the lake and dampen fluctuations in population levels, while improving the quality of sport fishing, explains the DG. The spawning grounds we have created, including the two phases, are distributed within a three to four kilometer radius at different depths. »
The impact of the first 25 spawning grounds created in 2017 was quickly felt on smelt reproduction.
Photo provided by CLAP
In order to transport the stones necessary for the formation of the spawning grounds, very large dump trucks had to be used.
“We tracked the results over six years and reviewed the numbers every two years. On average, the sector produced three times as much young smelt during the three years as before development. If we take into account that the spawning areas we currently have are three times larger, if we apply a rule of three the sector should produce nine times more young stints. »
The location was not chosen at random. “The site chosen for our development is the only known sector where smelt spawn in Lac Saint-Jean, whether abundant or not. No one can understand what he is doing there, especially as the spawning grounds are lapped by the lake’s three major tributaries directly opposite, the Péribonka, Mitassini and Ashuapmushuan rivers. The bottom of the lake is sandy here. In the spring, when there is a great flood, the eggs are transported into the lake and sometimes torn on the stones. After ten years of research, we are sure that it is. »
BUILD A SPAWING AREA
Faced with this recurring situation, specialists have decided to create artificial spawning grounds where smelt reproduce naturally.
“It had to be done in this place to make it a [milieu] course for melting. Once we complete phase 2, we will have designed an area equivalent to two soccer fields. I would like to note that zander, a species very popular with anglers, will also benefit. »
Developed spawning grounds consist of slabs of large round stones lying on the lake bed at a depth of 1 to 2 meters above the lowest lake level, which is 14 feet in summer. They are up to 25 meters long and 18 meters wide and between 0.5 and 1 meter thick. A total of 6,300 tons of stone is used to craft the spawning grounds, which equates to 420 dump truck trips.
Photo provided by CLAP
These machines seem very small on the immense ice of Lac Saint-Jean.
The total area developed since 2017 is more than 10,000 square meters.
Including the results monitoring program through 2025, the capital expenditure on the project will be $558,000. CLAP, which invested $69,000, has three MRCs: Lac-Saint-Jean, Sépaq ($155,000), City of Alma ($150,000), Rio Tinto ($75,000), Resolute Forest Products ($40,000) and Wildlife Partners include Foundation ($40,000) and the Caisses Desjardins du lac Saint-Jean ($29,000). As a final word, Marc Archer said: “The best result we have achieved after the first phase is the record fishing season in 2020, the best in 25 years. »
Photo provided by CLAP
Seeing this person at the center of one of the 21 new spawn spots gives us a real sense of the importance of the work.
