The American Eel, a species unknown to many Canadians, experienced a 90% population decline throughout the last century and was listed as a species at risk in Ontario in 2007. Although developments of waterways has imposed lethal threats to the species, conservation initiatives throughout eastern Canada are determined to discover methods and locations for tagging eels, and developing long term goals for re-establishing safe migration routes for the species.
Despite the large geographic distribution of the American Eel, they are panmictic and are considered to be one population. A change in population within one region affects the species as a whole. The three major catalysts to the declining population are habitat destruction, commercial harvesting, and development of hydroelectric dams, which create barriers to migratory paths, and house turbines that contribute to higher injury and mortality rates of the eels. As the eel approaches maturity - between 17 to 25 years - the population migrates from the inland North American waterways towards the Atlantic Ocean for spawning. The eel’s life ends after reproduction. Any eel killed in the waterways has not reached the spawning grounds and therefore has not contributed to the drastically declining population.
Ontario was the first to actively protect the American Eel population as the province closed commercial fishing of the species in 2004 and subsequently listed it as endangered under the Ontario Endangered Species Act three years later. A historical initiative occurred last summer as an interprovincial alliance for the eels was solidified on July 14, 2014 at Voyageur Provincial Park. Members from Hydro Quebec, Ontario Ministry of Natural Resources and Forestry, Algonquins of Ontario, Canadian Wildlife Federation, and Quebec Ministry of Natural Resources joined together in a ‘trap and transfer’ program involving a swarm of 420 juvenile American eels, an initiative hailed as the “first ever known transfer of American eels into the Ottawa River.” Together, volunteers and the members from all organisations, tagged each eel with identification, and released the swarm further downstream in the Ottawa River. This process allowed the swarm to bypass the hydroelectric dam barrier.
The Canadian Wildlife Federation (CWF) is an active player in the efforts to rejuvenate eel populations in the National Capital Region. The CWF is an eel-passionate team with the objectives to conserve the population through documenting movement patterns, habitat preferences, and downstream migration timing. During the summer of 2014, the CWF targeted the lower reach of the Ottawa River. The team redistributed eels with implanted PIT tags containing an unique identification code which would allow recaptured eels to be identified in the future. Additionally, the team monitored eel ladders that are “a type of fish passageway placed at an upstream barrier, and resemble a peg board which allow for juveniles to move their way upstream” preventing injuries inflicted by turbines in hydroelectric dams.
Upcoming in summer 2015, the CWF team will replace the passive tagging method with an acoustic tag, which will release a continuous series of ‘pings’. The eels’ movements will be monitored by an acoustic telemetry system. Through testing of the receivers this past season, the CFW team now knows the optimal locations for tracking the eels’ movements.
Anyone can help conservation efforts by reporting eel sightings. If an eel is caught, it’s size, location of capture, and the date should be reported to the local Ministry of Natural Resources (MNR). Similarly, if a dead eel is found, the specimen should be brought to the local MNR office. Calcified rings on the eel’s inner ear bone can be used to determine age and it can help biologists assess the population structure.