Please enable JavaScript.
Coggle requires JavaScript to display documents.
American Eel - Coggle Diagram
American Eel
Population Trends
-
American Eels are an indicator species, meaning that the health of its population is an indicator of good ecosystem health
-
Assessed as "threatened" by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2012
Currently has no status under the federal Species at Risk Act, meaning they're not legally a species at risk in Canada
-
-
Recruitment of young glass eels to areas of historically high numbers, like the St. Lawrence River area, has been in decline for a while
Recently, these declines have slowed and stabilized, however it has yet to have a result on eel populations
-
Overall declining numbers seen in glass eels, yellow eels and silver eels
Actions Taken
In 2010, EU members suspended all exports and imports of European Eel commodities
-
In 2004, the Ontario Ministry of Natural Resources officially closed all commercial fisheries of eels due to the dramatic decline of eels in Lake Ontario and the St. Lawrence River
In 2007, eels in Ontario were officially classified as "endangered"
In 2008, Indigenous communities in Canada prepared an Aboriginal People's American Eel Resolution suggesting the eels be labeled as "endangered" and stated their willingness to give up their long-standing rights with eels to save them
Signed by the Algonquins of Ontario, the St. Lawrence Iroquois (represented by the Mohawks of Akwesasne) and the Mi'kmaq of the Maritimes
Dam removal and installation of eel ladders along the U.S. portion of the range is now a common restoration strategy, however, strategies to protect downstream migration though hydroelectric facilities are rare.
-
Eel ladders!
First one was added to the St. Lawrence River in 1974 to help eels cross the two major hydroelectric dams on the river
-
Drivers of Decline
Biological resource use
Commercial Harvest
Worldwide demand for eels has outpaced wild populations, so eel farming is growing
Eels can't be raised from eggs effectively, has to start with glass eels (captive reproduction isn't possible)
In Asia, wild-caught glass eels and elvers are farmed to marketable sizes
There's a worrying practice already where one Anguilla species is overexploited, so the industry moves on to the next in order to fill demand
Eel farming is responsible for over 90% of all Anguilla production worldwide (average of 280,000 tonnes per year since 2007)
Maine and South Carolina are the only 2 U.S. states that still allow commercial fishing of glass eels
BUT, as demand increases, poaching has been reported in several states
-
-
Other uses
Historically, glass eels and elvers have been commercially fished for striped bass bait to supply farms in Asia
Aboriginal people use them for sustenance, reverence and practical purposes
-
Pollution
Lethal toxicity from chemical contaminants has been known to occur in St. Lawrence eels for more than 30 years
High concentrations of chemicals in migrating silver eels in the gonads; could exceed threshold toxicity for larvae
PCB levels in eels have been so high that commercial harvest of eels for consumption has been banned throughout the Hudson River south of Glen's Falls, NY
-
Climate change
-
Changes in oceanic primary production as a result of climate change has reduced food available for eel larvae and caused population decline
Natural History
Anguilla rostrata
Eels are ancient, lived on earth more than 100 million years
-
Appearance
Females can grow longer than 1 meter, and weigh around 7.5 kg
Males are smaller, growing to only 0.4 m long
Colour varies from olive green and brown to greenish-yellow, with a light grey or white belly. Females turn dark grey or silver when they mature.
Muscular, with girth like a man's forearm
-
Many names in Canada
The Atlantic Eel, the Common Eel, the Silver Eel, the Yellow Eel and the Bronze Eel
Indigenous languages
-
-
-
In Cree, it's Kinebikoinkosew
