Summer 2016 an 'exceptional' year for biodiversity in St. Lawrence River

From North Atlantic right whales to narwhals to sunfish, this summer has proven to be a banner year for biodiversity in the St. Lawrence River.

From North Atlantic right whales to narwhals to sunfish, biologist says it's been a banner year

Sunfish are one of many species being spotted more often in the St. Lawrence this summer. When the fish are seen at the surface of the water, they’re usually trying to warm up, using the warmth of the sun, to conserve their energy for hunting prey. (Submitted by Lyne Morissette)

A Quebec marine biologist says this summer was "exceptional" when it comes to the diversity of species spotted in the St. Lawrence River. 

Lyne Morissette said the most noticeable new visitors were whales — since last year, North Atlantic right whales, the most endangered whale in the world, have been making appearances from the Gulf of the St. Lawrence all the way to Tadoussac.

Narwhals usually live in the Arctic, but one was spotted near Trois-Pistoles, Que. this summer. (Paul Nicklen/WWF)

Also this summer, a narwhal was spotted near Trois-Pistoles. Dubbed the unicorn of the sea, narwhals look like beluga whales, but males have long tusks that grow right through their upper lip.

A capelin is a small forage fish eaten by cod and whales. (Craig Purchase)

Morissette said the narwhals are usually found in the Arctic, making the sighting "quite unusual."

And with the proliferation of cell phones and social media, the stars of the St. Lawrence are getting much more airtime, Morissette said, mentioning the French tourists that had a close encounter with a finback whale earlier this month.

Whale close encounter in Tadoussac

7 years ago
Duration 0:37
Whale watchers in Tadoussac got way closer to the sea mammal than they expected.

Not just whales, fish sightings up too

Morissette said observers have spotted more capelin than in summers past. Capelin are small fish that serve an important role in the ecosystem, feeding whales, seals, cod and sea birds.

She said in some places off the Gaspé coast, there are so many capelin that if you take a bucket out into one foot of water, you could catch a few.

There have also been more sightings of sunfish, which Morissette described as "a big plate that swims in the ocean."

She said the fish are usually seen in warmer waters further south of Quebec, off the coast of Boston and Louisiana, so their appearance in the St. Lawrence is "definitely a sign of changes in our environment."

Warmer water leads to changes

There's no way to know for sure why the fish and whales are migrating to the St. Lawrence, but Morissette said the area is a great habitat for right whales.

"Maybe they found something here that is suitable for them. Less threats, more food, we don't know for sure," she said.

One explanation could be the warmer water — the water temperature is about two degrees higher than it was a decade ago, she said.

"All species will adapt to that, either physically [to] be able to live in the warmer environment, or they'll move somewhere else" and be replaced by warm-water species moving north, she said.

​Sunfish, for example, eat jellyfish, which can adapt quickly to rising water temperatures. Morissette said it's possible there are more jellyfish in the St. Lawrence these days, and the sunfish are following their food north.

While we all need to be cautious about the warmer water, Morissette said she's excited that more people are taking an interest in the river.

"[Oceanographer] Jacques Cousteau said we protect what we love and we love what we know, and the best way to know things is to go at sea and live the St. Lawrence," she said.

with files from CBC's Quebec AM