Eels at the Edge: Science, Status, and Conservation Concerns

American Eel Movements, Growth, and Sex Ratio Following Translocation

Guy Verreault, Willy Dargere, and Rémi Tardif


Abstract.—Forty thousand American eel Anguilla rostrata elvers were released in a 400-ha lake in an eel-free watershed in eastern Québec in 1999. Subsequent sampling enabled the measurement of poststocking movements, growth, and sex ratio. Populations showed limited movements, and occupancy extended less than 3 km into inflowing tributaries by 2003. Annual growth increments in the lake (118 mm/ year) were the highest reported for the species, but growth increments in rivers (40 mm/year) were typical of those found elsewhere. Four of seven eels whose sex could be determined were females, in contrast to other sites in the St. Lawrence watershed where females are more than 99% of the population. American eel translocation to growth areas that have been blocked by artificial barriers may be a useful means to increase production of silver eels.