Time for Nature

Restoring the Speckled Trout at La Mauricie National Park of Canada

January 12, 2009

La Mauricie National Park of Canada

This lake that was once devoid of life will soon have thousands of fish swimming in its waters.
© Parks Canada / Jacques Pleau

The calm of a peaceful forest lake is broken only by ripples of frantic movement in the water. Just below the surface, the spawning ground of a large group of Speckled Trout is a buzz of activity. Full grown fish are busily cleaning the bottom in preparation for the next group of eggs. This lake that was once devoid of life will soon have thousands of fish swimming in its waters.

Troubled Waters

La Mauricie National Park of Canada is defined by a landscape of forests, hills, varied streams, waterfalls and abundant lakes. These lakes in the heart of the Laurentians were once teaming with life. However a long history of log driving, construction of dams and the introduction of non native fish have greatly altered the integrity of the aquatic environment. An observable indicator of this phenomenon is the sharp drop in Speckled Trout populations.

Also called Brook Trout, the Speckled Trout is the most representative fish species of La Mauricie National Park. This highly sought after fresh water fish was once the only native species of fish in over 120 lakes. Today, they are present in only 55 lakes alongside introduced species. It is estimated that there has been a 50 percent drop in Speckled Trout productivity in the last 50 years.

A Bold Plan

Releasing Speckled Trout alevins in Tessier Lake
© Parks Canada

One central goal of the aquatic environment restoration project “From Log to Canoe” is the improved protection of indigenous species. In an effort to restore the ecological integrity of the aquatic habitats within the park, officials at La Mauricie National Park have taken the initiative of reintroducing the Speckled Trout into certain lakes such as Tessier Lake. Park officials suspect that prior to the creation of the park, Tessier Lake may have been emptied of fish by poaching.

The group of fish chosen to be reintroduced had to be drawn from a similar nearby lake. The progenitors selected were therefore extracted from Waber Lake and the alevins conceived in the controlled environment of an artificial spawning ground.

The Big Day

May of 2005, on a cool spring day, 14,000 Speckled Trout alevins were released into Tessier Lake. By the spring of 2007, this same group had not only survived and grown into adult fish, but were already reproducing. This was a year ahead of the predicted schedule proving that Mother Nature can be full of surprises.

Hope for the Future

Also called Brook Trout, the Speckled Trout is the most representative fish species of La Mauricie National Park.
© Parks Canada / Maxime Déry

But how will the trout adjust to a new habitat that was previously unoccupied for several years? That’s what imminent Biologists Louis Bernatchez of l’Université Laval and Pierre Magnan of l’Université du Québec à Trois-Rivières, plan to find out. Their ongoing studies will help them understand this new population of Speckled Trout and even trace the origins of individual fish to their family branches in order to calculate the survival rate among families.

Careful monitoring of this group of re-introduced fish will help map the way for further restoration projects at La Mauricie National Park of Canada. The enormous care and efforts put forward by dedicated people such as Parks Canada staff will go a long way toward restoring and preserving the ecological integrity of our wild places.