Productivity and spawning patterns are changed; 

 Local food species of adults, juveniles, fry, or 

 larvae are affected (Council on Environmental 

 Quality, 1974: 107, 109). 



Moore and Dwyer (1974: 819-827) describe five ways indi- 

 vidual organisms including birds respond to the effects of oil pollu- 

 tion. The first is direct lethal toxicity , resulting in death. 

 Cellular and sub-cellular processes, especially membrane 

 activity, are interfered with by the hydrocarbons released 

 by crude oil. The most toxic of the hydrocarbons (the 

 chemical components of petroleum) are the lower boiling 

 point aromatics. These stay in the environment the longest. 



The larva and juvenile species are more sensitive to 

 toxic matter than the adults. Adult marine organisms respond 

 to lethal toxic levels from concentrations of soluble 

 hydrocarbons in the 1 to 100 parts per million (ppm) range. 

 Larval stages may be affected by levels as low as 0.1 ppm. 



The second response is sub-lethal disruption of physio- 

 logical or behavioral activities. Disruption of cellular 

 and physiological processes does not include immediate 

 death, though it may occur in the long-run. Feeding and 

 reproduction of species are possibly affected. 



Direct coating of oil is the third response. This can 

 cause smothering of the species and/or interference with 

 feeding and movement. Oil can also destroy the waterproofing 

 and insulating properties of animals with feathers and fur. 



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