SPECIES BIOLOGY 



Anadromous Atlantic salmon have a relatively complex life history that extends from spawning 

 and juvenile rearing in freshwater rivers to extensive feeding migration in the high seas. Adult 

 Atlantic salmon ascend the rivers of New England beginning in spring, a migration that peaks in 

 June and continues into the fall. Juvenile salmon feed and grow in the rivers from one to three 

 years before undergoing smoltification and migrating to the ocean. Atlantic salmon of U.S. 

 origin are highly migratory, undertaking long marine migrations between the mouths of U.S. 

 rivers and the northwest Atlantic Ocean where they are widely distributed seasonally over much 

 of the region. Most Atlantic salmon of U.S. origin spend two winters in the ocean before 

 returning to freshwater for spawning. Those that return after only one year are called grilse. 



SPECIES DISTRIBUTION 



The populations of anadromous Atlantic salmon present in the Sheepscot, Ducktrap, 

 Narraguagus, Pleasant, Machias, East Machias. and Dennys rivers represent the last wild remnant 

 of U.S. Atlantic salmon. Restoration efforts for Atlantic salmon are ongoing in other watersheds 

 where the locally-adapted stock has been extirpated. 



MAJOR IMPACTS 



The construction of hydropower dams with either inefficient or non-existent fishways was a 

 major cause for the decline of U.S. Atlantic salmon. Dams adversely impact Atlantic salmon by 

 impeding both their upstream and downstream migration, increasing predation, altering the 

 chemistry and flow pattern of rivers, increasing water temperature, and reducing available flow 

 downstream. Currently there are no hydropower dams on the seven rivers that have the potential 

 to adversely impact the species. Beaver and debris dams have been documented on these river 

 and may partially obstruct passage. 



One of the predominant land uses of the central and northern coastal Maine watersheds is the 

 growth and harvest of forest products. Forest management practices can cause numerous short- 

 and long-term negative impacts to Atlantic salmon, including siltation. shade reduction, and 

 increased water temperature. Another significant land use in eastern Maine watersheds is 

 lowbush blueberry agriculture. In addition, interest in cranberry cultivation is increasing . These 

 agricultural activities can impact Atlantic salmon through water extractions and diversions and 

 pesticide application. Currently regulatory mechanisms are in place such that forest practices 

 and agricultural practices are not considered a major threat to Atlantic salmon. 



Historically, the marine exploitation of U.S. origin Atlantic salmon occurred primarily in foreign 

 fisheries. U.S. origin Atlantic salmon have been documented in the harvests of West Greenland, 

 New Brunswick, Nova Scotia, Newfoundland, and Labrador. The U.S. is a party to the North 

 Atlantic Salmon Conservation Organization (NASCO) which was formed for the purpose of 

 managing salmon through a cooperative program of conservation, restoration and enhancement 

 of North Atlantic stocks. Since 1987 there has been a FMP in place which prohibits the 

 possession of Atlantic salmon in the EEZ. There is currently a limited catch and release fishery 

 for Atlantic salmon in these seven Maine rivers. 



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