BURNABY — A nightmarish fish pulled from a pond in a suburban Vancouver park last year likely wouldn’t have survived a Canadian winter, but scientists remain concerned about North America’s vulnerability to invasion from non-native species.
Scientists from Simon Fraser University, the universities of British Columbia and Guelph, as well as the B.C. Ministry of Environment examined the half-metre-long, 3.7-kilogram fish and determined the toothy monster was a blotched snakehead, not the northern species which tolerates cold conditions and could survive in Canadian waters.
The snakehead can slither overland and has a lung that allows it to survive out of water for short periods, but the researchers found no evidence of eggs in the Burnaby pond where it was found, confirmed it was not born there, and say the creature’s internal tissues match those of less hardy blotched snakeheads that at the time could be purchased in Greater Vancouver.
Discovery of the voracious fish raised concerns that it could invade the Fraser River, threatening salmon stocks and other native species, so the environment ministry banned possession, transport and breeding of all species of snakeheads.
The United States did the same more than a decade ago, yet scientists say invasions of the voracious fish are still reported and various snakehead species are now well established in the fresh waters of Hawaii, Florida and the eastern U.S.
The study, published online in the Management of Biological Invasions Journal, urges continued monitoring and rapid response planning to deal with invasive species and says public education is key to highlighting the severe environmental and economic consequences linked to release of any non-native species of fish.