Two diseases are causing decreased growth rates and increased mortality among wild and farmed oyster stocks on the Eastern Seaboard of Canada [1].
The spread of these pathogens threatens the regional aquaculture industry and the biological health of oyster populations, particularly in Prince Edward Island [2].
The affected populations are battling two specific diseases: Multinucleated Sphere Unknown, known as MSX, and Dermo, also called Perkinsosis [1]. These diseases have spread northward this season, which was identified as 2024 [1], [2].
In response to the crisis, the federal government announced nearly $12 million [3] in new measures to support the hard-hit oyster industry in Prince Edward Island. Of that total, Fisheries and Oceans Canada allocated $6 million [3] specifically for a buy-back program.
To combat the mortality rates, Canada has approved the import of oyster broodstock [2]. This measure aims to introduce more resilient genetics to the local populations to tackle the ongoing disease crisis [2].
While some reports from other regions suggest certain oyster populations remain robust, Canadian officials and industry observers said that these two diseases continue to harm stocks along the Eastern Seaboard [1], [2].
“Two diseases are causing decreased growth rates and increased mortality among wild and farmed oyster stocks.”
The northward migration of MSX and Dermo suggests that warming waters may be expanding the habitable range for these pathogens. By combining financial relief via buy-back programs with the introduction of foreign broodstock, Canada is attempting to pivot its aquaculture strategy toward genetic resilience rather than relying solely on the natural immunity of local stocks.
