1999 

 OUR LIVING OCEANS 



catch is composed ot fish and shellfish thac depend on estuaries at some critical stage in 

 their lite cycle. 



Mangrove roots, Florida 

 Keys, Florida. 



Until qtiite recently, the United States was losing wetlands at a rapid rate. The Clean 

 Water Act and other Federal environmental laws have heen instrimieiual in decreasing 

 wetland losses since that time. During 1982-92, the losses totaled 31 ,()()() acres ol wetland 

 per year, down From 1 57,000 acres per year in 1 974-83, and down hnther trom the 398,000 

 acres per year in 1954-74. However, despite regulatory programs and natural resource 

 management plans, human population growth and development coiitintie to result in a net 

 loss of habitat acreage and function. 



In addition to the coastal and estuarine habitats, fishery managers must also extend 

 their concern to the riverine and riparian ecosystems of anadromous species and to the 

 deeper ofishore ecosystems that support migratory and pelagic species. Although many fish 

 stocks are stable in Alaska, many other west coast salmon stocks are so diminished that they 

 are now listed, proposed for listing, or under consideration for listing under the ESA. 

 Declines in abundance have been attributed to habitat loss and degradation Irom the cu- 

 tnulative impacts ot human activities, including hydropower dams, irrigation diversions, 

 logging, mining, grazing, urbanization, etc. hoss ot these species trom their traditional 

 river reaches has devastating effects on the biological integrity ot those ecosystems. 



Although pelagic fishes usually are not correlated with the types ot areas commonly 

 thought of as fish habitat (e.g. wetlands and bottom substrate), physiographic and hydro- 

 graphic structures with which migratory pelagic tishes are otten associated (e.g. seamounts, 

 current boundaries, temperature discontinuities) can be characterized as habu.u. In spite ot 

 the distance trom shore, these habitats are susceptible to adverse ettects trom both inshore 

 and oftshore activities due to the transport ot materials to these locations, and to damage 

 (e.g. to seamounts) caused by certain types ot tishing gears. 



Many changes in the environment are not directly caused by human activities. For 

 example, the decline in ocean survival tor coho and chinook salmon in the Pacific during 

 the last 2 decades coincides with a change in the oceanographic regime oti the west coast. 

 As another example, the abundance of some species, notably sardine and anchovies, typi- 

 cally oscillates in c\'cles that last tor decades. In ail eases, however, human actions can 

 accelerate the declines in pojnilation either trom other changes to the habitat (e.g. tor 



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