Written by Eric Mysak, Specialist, Freshwater
Recently, two Asian carps were caught in two separate ponds near Lake Ontario -- a discovery that is particularly worrisome given that species' notoriously invasive reputation.
First brought to North America in the 1970s in a misguided attempt to control algae and plant growth in the southern United States, the Asian carp, known as a prolific eater and breeder, has since established itself as a dominant species, out-competing native fish populations as far north as the Canadian border.
While it has yet to be determined how these two fish made their way into these ponds and whether the Asian carp can truly be classified as an invasive species in the Great Lakes at this point, the negative impacts of non-native species on biodiversity isn't a new threat in the Great Lakes watershed. Zebra mussels, sea lampreys, Eurasian water milfoil -- these are only a few of the many invasive species that have established themselves here. And undoubtedly, for those of us privileged to spend time by a river or a lake during the summer months, the impacts of these invaders are all too familiar.
The sun shines brightly in a blue sky over the shores of Lake Ontario, Ontario, Canada. © Frank PARHIZGAR / WWF-Canada
In fact, invasive species are one of the biggest threats facing the health of the Great Lakes watershed. WWF recently launched Watershed Reports assessing the health of Canada's watersheds and the threats they face. Among the 12 major watersheds assessed to date, the Great Lakes watershed is the only one where the threat of invasive species scored Very High. The threat of invasive species is found to be highest in the southern half of the watershed -- an area that includes the Lake Ontario and Niagara sub-watershed, where the Asian carps were recently found.
Without question, the Asian carp poses a significant threat to the health of the Great Lakes watershed. This highlights the importance of effective invasive species prevention programs and bi-national collaboration to ensure that the Asian carp and other non-native species don't make their way into these waters. The proposed Invasive Species Act in Ontario is certainly a positive step in that direction. If passed, the Act is one measure that would help strengthen our defenses against invasive species.
But individual actions can also go a long way in the fight. One way to help is with the Early Detection and Distribution Mapping System - a web platform that encourages people to step into the role of citizen scientists and report potential invasive species sightings.
Protecting the health of the Great Lakes watershed against the threat of invasive species is a challenge truly requiring collective and concerted action.