Research Document - 2011/050

2010 Update on the status of American Eel (Anguilla rostrata) in Ontario

By T.C. Pratt and A. Mathers

Abstract

American Eel (Anguilla rostrata) once comprised an important component of the fish community, and supported significant commercial fisheries, in the Ottawa River and Lake Ontario / upper St. Lawrence River watersheds in the Province of Ontario. These eels were large, fecund females, and it is estimated that eels from these watersheds comprised over 50% of the potential fecundity from Canadian waters. Today, eel recruitment to Ontario waters has declined by approximately 97% since the early 1980s. A slight rebound in recruitment is apparent since 2004. Two fisheries-independent yellow eel abundance indices show similar declines over the same timeframe, and the species is now listed as Endangered under the province’s Endangered Species Act (2007). Restrictions to rearing habitat access have resulted in significant lost production potential, estimated to be over 250,000 silver eels from the Ottawa River watershed alone. Recovery of abundance and distribution within the waters of Ontario will depend on improved production and enhanced density-dependent dispersal of recruits from the Sargasso Sea. Therefore, threats that occur outside of Ontario are as important as threats from within the province. Potential threats include harvesting, loss of habitat access, habitat alteration, productivity and food webs alterations, turbine mortality, parasites, and toxins and contaminants.

Complete document (PDF, 279 KB)

Accessibility Notice

This document is available in PDF format. If the document is not accessible to you, please contact the Secretariat to obtain another appropriate format, such as regular print, large print, Braille or audio version.