Declining Abundance and Recruitment of American Eels at the Extremities of the Range: From the Upper St. Lawrence River to the Upper Mississippi River

Wednesday, August 20, 2014: 9:20 AM
206B (Centre des congrès de Québec // Québec City Convention Centre)
John Casselman , Dept. of Biology, Queen's University, Kingston, ON, Canada
Lucian Marcogliese , Research Biologist, Ameliasburg, ON, Canada
Rob MacGregor , Ontario Ministry of Natural Resources (retired)
Peter Thompson , Department of Fisheries and Ocean (retired)
Ken Able , Rutgers Marine Field Station, Rutgers University, Tuckerton, NJ
Keith D. Clarke , Science Branch, Fisheries and Oceans Canada, St. John's, NF, Canada
Heather Corbett , N.J. Division of Fish and Wildlife, U.S. Bureau of Marine Fisheries
J. Christopher Taylor , Center for Coastal Fisheries and Habitat Research, NOAA National Ocean Service, Beaufort, NC
Quinton Phelps , Big Rivers and Wetlands Field Station, Missouri Department of Conservation, Jackson, MO
American eels have declined dramatically in some regions over the past several decades, best documented in the upper St. Lawrence River-Lake Ontario, where the species is now classified as endangered; some have suggested that this has a local explanation. We examined changes in abundance across the range from the upper St. Lawrence River along the Atlantic Seaboard, Gulf of Mexico, and Caribbean to the upper Mississippi River–19 datasets, encompassing two to five decades, 12 locations. Changes in fisheries-independent indices that are short term or near the source of recruitment (southern, Gulf Stream) are less apparent, often with no significant trends. Comparison of long-term glass eel recruitment for NJ and NC shows significant decreases in abundance and delays in ingress with extremity, both showing decreased size. Recent increases in recruitment in some locales are not appreciably greater than seen in the past few decades and might be explained by oceanic changes (North Atlantic Oscillation Index) and possible management actions. If recruitment and abundance data are from the extremities and long enough, declines are apparent, widespread, and consistent with overall species decline, emphasizing the need for universal action to reverse these trends. We consider this panmictic species threatened and the resource endangered.