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

Are American Eel Harvests in Maryland’s Chesapeake Bay Sustainable?

Julie A. Weeder and James H. Uphoff, Jr.


Abstract.—We investigated yield per recruit and spawner biomass per recruit of American eels Anguilla rostrata in five commercially fished estuarine river systems to determine population status, using a modified form of the Thompson-Bell model. We estimated three biological reference points with this model: Fmax, F0.1, and Freplacement; eels appeared overfished relative to these reference points. Current fishing mortality rates (F) ranged from 0.37 to 1.19, while Fmax ranged from 0.33 to 0.51, F0.1 ranged from 0.24 to 0.35, and Freplacement ranged from 0.20 to 0.32. The percentage of maximum spawning potential (%MSP) needed for replacement of the stock was estimated at 33%, but current %MSP varied between 1% and 28%. ICES guidelines recommend that F equal M in data-poor situations, but Fs in Maryland’s upper Chesapeake Bay were two to four times larger than M. American eel populations in the Chesapeake Bay region may now depend on recruitment from other areas along the Atlantic coast where fishing mortality is low.