ntial barriers to spawning runs. Migration of adult Atlantic salmon may be limited by beaver dams during periods of low stream flows, but the presence of juvenile Salmo salar upstream from the dams suggests the dams are penetrated by parr. Downstream migration of Atlantic salmon smolts was similarly unaffected by beaver dams, even in periods of low flows. A 2003 study of Atlantic salmon and sea-run brown trout/sea trout (Salmo trutta morpha trutta) spawning in the Numedalslågen River and 51 of its tributaries in southeastern Norway were unhindered by beaver. In a restored, third-order stream in northern Nova Scotia, beaver dams generally posed no barrier to Atlantic salmon migration except in the smallest upstream reaches in years of low flow where pools were not deep enough to enable the fish to leap the dam or without a column of water over-topping the dam for the fish to swim up. The importance of winter habitat to salmonids afforded by beaver ponds may be especially important (and underappreciated) in streams of northerly latitudes without deep pools where ice cover makes contact with the bottom of shallow streams. In addition, the up to eight-year-long residence time of juveniles in fresh water may make beaver-created permanent summer pools a crucial success factor for Atlantic salmon populations. In fact, two-year-old Atlantic salmon parr in beaver ponds in eastern Canada showed faster summer growth in length and mass and were in better condition than parr upstream or downstream from the pond.
Legislation[edit source | edit]
The first laws regarding the Atlantic salmon were started nearly 800 years ago.
England[edit source | edit]
Edward I instituted a penalty for collecting salmon during certain times of the year. His son Edward II continued, regulating the construction of weirs. Enforcement was overseen by those appointed by the justices of the peace. Because of confusing laws and the appointed conservators having little power, most laws were barely enforced.
Based on this, a royal commission was appointed in 1860 to thoroughly investigate the Atlantic salmon and the laws governing the species, resulting in the 1861 Salmon Fisheries Act. The act placed enforcement of the laws under the Home Office's control, but it was later transferred to the Board of Trade, and then later to the Board of Agriculture and Fisheries.
Another act passed in 1865 imposed charges to fish and catch limits. It also caused the formation of local boards having jurisdiction over a certain river. The next significant act, passed in 1907, allowed the board to charge 'duties' to catch other freshwater fish, including trout.
Despite legislation, board effects decreased until, in 1948, the River Boards Act gave authority of all freshwater fish and the prevention of pollution to one board per river. In total, it created 32 boards.
In 1974, the 32 boards were reduced to 10 regional water authorities (RWAs). Although only the Northumbrian, Welsh, northwest and southwest RWA's had considerable salmon populations, all ten also cared for trout and freshwater eels.
The Salmon and Freshwater Fisheries Act was passed in 1975. Among other things, it regulated fishing licences, seasons, and size limits, and banned obstructing the salmon's migratory paths.
Scotland[edit source | edit]
During the 15th century, many laws were passed; many regulated fishing times, and worked to ensure smolts could safely pass downstream. James III even closed a meal mill because of its history of killing fish attracted to the wheel. Because the fish were held in such high regard, poachers were severely punished.
More recent legislation has established commissioners who manage districts. Furthermore, the Salmon and Freshwater Fisheries Act in 1951 required the Secretary of State be given data about the catches of salmon and trout to help establish catch limits.
United States[edit source | edit]
Several populations of Atlantic salmon are in serious decline, and are listed as endangered under the Endangered Species Act (ESA). Currently, runs of 11 rivers in Maine are on the list