Atlantic Salmon in Maine (2004) / Chapter Skim
Currently Skimming:
Summary
Summary
Pages 1-15
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 1... ...
included an interim report that focused on the genetic makeup of Maine Atlantic salmon populations; that report was published in January 2002. The charge for the final report included a broader look at factors that have caused Maine's salmon populations to decline and the options for helping them to recover.
|
From page 2... ...
Dennys, (6) East Machias, (7)
|
From page 3... ...
In assessing information, the committee will identify significant knowledge gaps and suggest additional research that would be impor tant to the conservation and recovery of salmon populations. Factors to be evaluated include the nature and distinctness of salmon popula tions in Maine rivers and surrounding areas; the interactions between aquaculture, hatchery, and wild populations; terrestrial and marine environmental factors affect ing salmon populations; the effects on salmon of changes in the hydrology of Maine streams; and the effects on salmon of subsistence, recreational, and commercial fishing in freshwater and ocean areas in and around Maine.
|
From page 4... ...
Derived in part from European Atlantic salmon, the genetic strains used for fish farming are even more different from native strains than are hatchery strains. Farm fish escape at all life stages, despite the efforts of producers to prevent escapes.
|
From page 5... ...
Third, to what degree are salmon populations in the eight Maine rivers in the ESA listing distinct from each other? The committee concluded that North American Atlantic salmon are clearly distinct genetically from European salmon.
|
From page 6... ...
The forested area decreased dramatically as the combined effects of forest clearing for agriculture, industrial logging and milling, and subsequent forest fires reduced coverage to 53.2% by 1872. Forests have since regenerated on abandoned agricultural land and "cutover" areas, reversing the trend of deforestation of earlier centuries.
|
From page 7... ...
The committee's approach has been statewide, without a specific or exclusive focus on the eight DPS rivers or on the specific requirements of the ESA. That statewide approach was the committee's charge, and it has a sound scientific basis: much additional salmon habitat in other watersheds should be used in rebuilding salmon populations.
|
From page 8... ...
The available information is not sufficient to conclude whether hatcheries in Maine can actually help to rehabilitate salmon populations, whether they might even be harming them, or whether other factors are affecting salmon so strongly that they overwhelm any good that hatcheries might do. Aquaculture Salmon farms rear salmon from eggs in hatcheries and then grow them to market size in net-pens near the coast.
|
From page 9... ...
Although acidification has not been conclusively identified as a source of death for Atlantic salmon in Maine, recent information on poor survival of smolts and on water chemistry in Maine makes it appear that acidification could be a serious problem. Fishing Fishing has affected Maine salmon until very recently.
|
From page 10... ...
Continued warming would make it more difficult to rehabilitate wild salmon populations in Maine. Change in precipitation patterns and related phenomena, such as ice cover and timing of snowmelt, probably also would make things more difficult.
|
From page 11... ...
It would be helpful to increase coordination of efforts across local, state, federal, and international levels of organization; adapt governance structures to more closely match the biology and geography of salmon populations; include stakeholders in the risk-assessment and risk-management processes; and develop and improve of adaptive-management approaches that allow people to test the efficacy of various governance structures. RANKING THE THREATS The committee's risk assessment led it to conclude that the greatest impediment to the increase of salmon populations in Maine is the obstruction of their passage up and down streams and degradation of their habitat caused by dams.
|
From page 12... ...
The serious depletion of salmon populations in Maine underscores the need to expand rehabilitation efforts to as many of Maine's rivers as possible. Since most Maine salmon are now in the Penobscot River, that population should be a primary focus for rehabilitating the species in Maine.
|
From page 13... ...
Additional research on hatcheries and scientific guidance for their use is needed, because hatchery-based restoration of wild salmon populations remains an unproven technology. The committee was asked to provide estimates of the approximate relative costs of the various options.
|
From page 14... ...
Habitat zones most heavily used by Atlantic salmon young and adults should be closed to fishing for all species until salmon populations have recovered. · Research that increases the risk of death to wild fish should be curtailed.
|
From page 15... ...
That process could involve developing multistakeholder governance institutions for each drainage basin, each nested within larger scale governance bodies to address effects that are larger than individual basins, such as climate change and aquaculture. · The suite of additional options with multiple environmental benefits outlined in Chapter 5 should be adopted.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.