Land use changes and the destruction of riparian habitat are having im- 

 mense primary and secondary impacts detrimental to wildlife and fisheries 

 throughout much of the United States. Grazing, agricultural clearing, and 

 forestry practices are creating immediate losses of prime habitat for wild- 

 life. Valuable aquatic resources are then secondarily threatened or lost as 

 a result of increased sedimentation, often accompanied by numerous contamin- 

 ants that pollute lakes and streams. 



Extensive activities related to development and consumption of energy 

 sources have a high potential for detrimental impacts on fish and wildlife 

 resources. Toxic substances occurring in oil and coal include phenols, cre- 

 sols, water-soluble a'romatics (e.g., carcinogenic polynuclear aromatic hydro- 

 carbons), inorganics, and a new generation of organometall ics about which 

 little is known. Possible contaminants arising from energy development, 

 transport, use, and disposal are so numerous that it is difficult to know 

 where to begin in assessing problems and projecting research needs. 



Drilling and production of oil wells results in the use of large volumes 

 of contaminated water that must be disposed of. This wastewater may carry 

 dissolved aromatics or high levels of salts. Discharge waters in Wyoming 

 have allowable concentration of "oil and grease" of 10 mg per liter. Fin 

 erosion and 20 percent reduction in growth of trout was demonstrated at 100 

 ug per liter -- a 100-fold dilution of the maximum allowable concentration 

 (personal communication, Dan Woodward, CNFRL-Jackson, Wyoming Field Labora- 

 tory). Personnel at the Jackson Field Station have also found that trout 

 are attracted to oil concentrations in water that cause reduced growth and 

 survival . 



Combustion of fossil fuels is polluting precipitation with strong acids, 

 trace elements, and complex organic contaminants (Gorham 1976). Some 450 or- 

 ganic contaminants, including PCB's, DDT, various polycyclic aromatic hydro- 

 carbons, and others, have been detected in precipitation. Prevailing 

 weather patterns are such that the northeastern U.S. is subject to extensive 

 fallout of acids and metals in precipitation. Trace elements are higher in 

 precipitation in the Northeast than in the Midwest or the West. There is 

 currently a lack of information on the water chemistry and fish populations 

 of susceptible, low buffered lakes and headwaters in New England. Surveys of 

 selected lakes indicate that fish populations are virtually absent in waters 

 having a pH lower than 5.5. Lowland lakes are decreasing in buffering 

 capacity, and small headwater streams may be adversely affected particularly 

 during spring melts. 



Other present and future contaminant threats of national and regional 

 concern are becoming more apparent to resource managers and researchers. 

 Water loss and contamination of irrigation return flows by agricultural 

 chemicals are creating serious problems for valued fisheries in western 

 states. PCB's and PCB replacements will continue to be a contaminant stress 

 on fresh-water fisheries, as will the increasing numbers of accidental spills 

 of hazardous substances along our coasts and in inland lakes and waterways. 



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