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St. Andrews, NB — December 3, 2021 — Two aquaculture-origin Atlantic salmon were among seven adult fish collected on Nova Scotia’s Gaspereau River this year for breeding at Fisheries and Oceans Canada’s Coldbrook Biodiversity Facility, a hatchery where populations of critically endangered inner Bay of Fundy Atlantic salmon are maintained. DFO scientists reported the information at a recent update on salmon recovery efforts.
It is the second year in a row and the third time since 2017 that an escapee has been removed from the Gaspereau River. In each case, the suspected aquaculture escapee was isolated inside the hatchery and scale samples were taken to confirm its origin. After the fish were determined to be escapees, they were euthanized and the Nova Scotia Department of Fisheries and Aquaculture was notified according to information from DFO shared with ASF.
“Thankfully, staff at the hatchery recognized these fish looked different,” said Abby Pond, ASF’s director of New Brunswick programs who attended the DFO briefing. “Had they not noticed, a domesticated animal could have been bred into the live gene bank program, which is life-support for Inner Bay of Fundy wild salmon.”
Aquaculture salmon have previously penetrated the live gene bank. A 2018 public review of the program found European origin salmon were spawning in multiple inner Bay of Fundy rivers as late as 2012 and were unknowingly introduced to the Coldbrook Biodiversity Facility. As the report’s authors state, the only likely source of European salmon is the local aquaculture industry.
In addition to the Gaspereau River discoveries, four aquaculture salmon were captured this year at a dam on the Union River in Maine according to the state’s Department of Marine Resources.
ASF scientists also found three aquaculture salmon trying to enter the Magaguadavic River in Southwest New Brunswick. ASF has monitored the Magaguadavic River fishway at St. George since 1992. Escapees have been recovered every year and the vast majority cannot be traced to any known breach of containment.
Interbreeding between aquaculture and wild Atlantic salmon has been widely documented. It is estimated that up to 2 million industry fish escape annually around the North Atlantic. When domesticated salmon breed with wild fish, their offspring are less fit, contributing to population decline and collapse. Some escapees have been detected as far away as Greenland.
The effects of escaped aquaculture salmon are magnified in small populations, like those that persist in rivers around the Bay of Fundy and Gulf of Maine. DFO researchers estimate that when 10 per cent of adult returns in a river are aquaculture escapees, wild salmon begin to suffer negative consequences.
“We have worked with industry and government for years to implement ways of tracing escapees back to their owners so we can address the causes of these events,” said Kris Hunter, ASF’s director of Nova Scotia and PEI programs. “There are some promising developments on traceability in Nova Scotia, but progress has been incredibly slow and we are still only monitoring a handful of sites for escapees around Atlantic Canada.”
ASF is not aware of any reported escape events in Nova Scotia or Maine in 2021. In late August, a notice from New Brunswick’s registrar of aquaculture reported a net tear at a Cooke cage in Seeley’s Cove. Officials confirmed that a final report provided to the province from the company said three fish escaped.
As members of the North Atlantic Salmon Conservation Organization, Canada and the United States have committed to ending aquaculture escapes, yet the persistence of escapees in wild salmon rivers continues to threaten the sustainability of populations from Maine to the south coast of Newfoundland.
Images available on request