Terms of Reference & Advisory Report of the American Eel Stock Assessment Peer Review.

摘要

The American eel Anguilla rostrata is one of 15 species in the family Anguillidae. All are characterized by great adaptability to a wide range of aquatic ecosystems, and consequently are found around the globe. All reproduce at sea and are at least facultatively catadromous, meaning they use inland habitats. Their complex life history is documented well in the 2012 American Eel Stock Assessment report. Of note is the fact that the American eel, from its northern limit in Greenland down to its southern limit in French Guiana, is one population. In New Zealand, anguillid eels are revered as spirits as much as they are prized as food (Prosek 2010). In traditional North American Indian cultures, the same is true. The Iroquois Confederacy in New York State has an Eel Clan; many of the governing leaders are recruited from this clan. However, today, the American eel is all but extirpated from Lake Ontario drainages, and most members of the Eel Clan have never seen a live eel (J. Shenandoah, Onondaga Nation elder, personal communication). Eels were formerly extremely abundant in inland waters of eastern North America, colonizing lakes, rivers, streams, and estuaries. In Onondaga Lake in New York State, 17th century Jesuit missionaries noted with wonder that ...the eel is so abundant that a thousand are sometimes speared by a single fisherman in a night... (Clark 1849). American eels penetrated the major Atlantic waterways of North America, reaching the Great Lakes via the St. Lawrence River and the mid-western American states via the Mississippi as far as Minnesota (Eddy and Underhill 1974). Coastal eel abundances were very high, and during the spring, runs of recruiting glass eels would form walls of glass as they ascended barriers. Eel fisheries flourished well into the early 20th century. Eels were once an important food fish in the U.S., but today are mainly sold as bait or exported to Europe and Asia, where demand continues to be high. Declines in European and Asian eels drive the export fishery, and in particular, the export market for glass eels has commanded prices exceeding $2000/lb this year. The American eel stock status is depleted. The seeds of the current depletion lay in part in a fishing up/fishing down episode that occurred on American eels in the 1970s into the 1980s as export demand rose. Roughly during the same period, river damming intensified and hydroelectric facilities on dams caused additional mortality. A suite of stressors including habitat loss from dams or urbanization, turbine mortality, the nonnative swim-bladder parasite Anguillicolla, toxic pollutants, and climate change are all factors that act in concert with fishing mortality on American eel. Through a series of data analyses and modeling, the SASC has documented this depletion. The following Peer Review Report discusses the SASC stock assessment findings, comments on strengths and weaknesses, and makes recommendations for additional data needs and future assessments.