A new study from the University of Manitoba has discovered that lake trout can change their behavior due to the effects of climate change, which could have serious repercussions for their ecosystems.
Over an 11 year-period, researchers examined the feeding habits of lake trout at the IISD Experimental Lakes Area in northwestern Ontario. They discovered that the lake trout would relocate depending on the temperature of the water.
“These findings are important for understanding how lake trout and other temperature-sensitive fish will respond to climate change,” says Matthew Guzzo, the lead author of the study, told the University of Manitoba in an interview.
As Guzzo explains, the lake trout are able to react to changes in water temperature. When the water became too warm, the fish left the shallow water that’s more rich in food for deeper parts of the lake where the food quality is lower.
“When a top predator [like the lake trout] is forced to change what it eats, it impacts not only its own well-being, but the whole food web,” says Guzzo.
This could affect a variety of factors, including how much the lake trout can grow and how much it can produce eggs and spawn. In the long run, this could affect the overall lake trout population.
“Lake trout are a sentinel species – the canary in the coal mine for boreal lakes,” says co-author Paul Blanchfield. “Our findings provide evidence that lake trout are struggling to cope with a rapidly-changing and stressful thermal environment.”
There is a silver lining though: since the lake trout have shown their adaptability, the species could continue to adjust in the future and remain prosperous.
“The current study isn’t the whole climate change story. It’s showing that fish can adapt to changing conditions. Their behaviour is not static. They’re not just sitting ducks,” says Guzzo. “We are showing that for now, lake trout can continue to live in these areas by making the best of a bad situation.”