Wildlife 



Dissolved Oxygen 



In addition to the DO requirements for aquatic 

 organisms, the bottoms of areas used by wildfowl 

 must be kept aerobic to suppress botulinus 

 organisms. 



PH 



Aquatic plants of greatest value as food for 

 waterfowl thrive best in waters with a summer pH 

 range of 7.0 to 9.2. 



Alkalinity 



Waterfowl habitats, to be productive, should 

 have a bicarbonate alkalinity between 30 and 130 

 mg/1. Fluctuations should be less than 50 mg/1 

 from natural conditions. 



through biological magnification. Special consid- 

 eration must be given to keep edible wildlife safe 

 for consumption by humans. 



Disease 



Offal from poultry houses, meatpacking plants, 

 as well as other possible sources of disease orga- 

 nisms, must be excluded from areas supporting 

 wildlife to guard against transmission of such dis- 

 eases as botulism, fowl cholera, and aspergillosis. 



General 



Water quality suitable for fish and other aquatic 

 organisms will be adequate for wildlife. 



Salinity 



Salinity should be kept as close to natural condi- 

 tions as possible. Fluctuations in salinity during 

 any 24-hour period should be limited as follows: 



Natural salinity : permitted 



to 3.5^„ V/oc 



3.5 to n.5%c 2%c 



13.5 to 35.0^r A%c 



Light Penetration 



Optimum light requirements for aquatic wildlife 

 habitats should be at least 10 percent of incident 

 light at the surface to a 6-foot depth; the tolerable 

 limit should be 5 percent of the light at the surface 

 to the same depth. 



Settleable Substances 



Settleable substances destroy the usefulness of 

 aquatic bottoms for waterfowl. Settleable sub- 

 stances should be excluded from areas expected to 

 support waterfowl. 



Oil is an especially dangerous substance to 

 waterfowl. Oil and petrochemicals must be ex- 

 cluded from both the surface and bottoms of any 

 area used by waterfowl. 



Toxic Substances 



Toxic substances should be excluded from 

 wildlife habitats to the degree that they affect the 

 health and well-being of wildlife, either directly or 



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