According to Fisheries and Oceans Canada, the northern shrimp population in the Gulf of St. Lawrence has dropped by 50 per cent in the past 10 years, with commercial fishermen catching roughly 30 per cent fewer shrimp between 2015 and 2016.
"It's almost at the point where you wonder whether it's worth going out," says shrimp fisherman, Sylvain Bujold. In his 20 years experience his boat is now catching nearly half of their expected yield - a significant drop for one of Eastern Canada's three most valuable fisheries.
Piero Calosi, a member of the Ocean Acidification CoP Steering Committee and a biology professor at Université du Québec à Rimouski said the recent drop in northern shrimp stocks is an anomaly that could last several years. However, he added it could also be indicative of a future trend.
"We have a very important signal of what could happen to the fisheries of shrimp and other fisheries in 50 years or 60 years," said Calosi.
While the exact cause of the shrimp stocks decline may be complex, the warming temperatures of the Gulf of St. Lawrence have been identified as a potential problem for the cold-water northern shrimp found in the northwest Atlantic.
Another factor is an increasing number of redfish, commonly referred to as the ocean perch, a species which prefers warmer water temperatures. Redfish compete with juvenile shrimp for food while also feeding on adult shrimp.
Ocean acidification may also be a contributing factor - with a lower pH and reduced aragonite saturation in ocean waters shrimp experience greater difficulty producing their hard outer shells.
With multiple stressors affecting the shrimp population, it is not easy to predict what will happen and several scenarios need to be studied, Calosi said. This will include considering whether the shrimp fishery may eventually end.
In September 2018, Calosi and a team of researchers from the university started a three- to four-year project on the global viability of the North-Atlantic shrimp fishery.
The project will consider the economic and social impacts that changes to the fish stocks could have on the communities that depend on them.
In 2014 alone the shrimp fishery brought in $489 million for the Canadian economy.
This article was adapted from CBC News by Heather Almeda. 2018.
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