65. 



weeks of cycles of contraction and excess mucous production 

 the coral eventually slough off their tissue layer and die. 

 This excess mucous also provides a suitable habitat for 

 bacteria, many of which are harmful to the coral (H. W. Ducklow, 

 personal communication) . In fact, these bacteria frequently 

 respond to stress on the host coral by growing in higher 

 concentrations (Ducklow and Mitchell, 1979) . Additionally, 

 alterations to the water column that affect its nutrient flux, 

 such as causing a decrease in primary productivity, could 

 increase coral mortality by decreasing the available nutrients. 

 At present it is necessary to obtain a more comprehensive 

 understanding of the environmental processes that affect the 

 epifaunal components of the continental margin on both the 

 slope and in the canyons. Only then will accurate assessments 

 of the impact of resource development be feasible. This 

 study has identified some of the possible mechanisms by which 

 resource development could be deleterious. But at present 

 these conclusions should only be viewed as exceedingly tentative, 



SUMMARY 



For the field study three major canyons were surveyed 

 using a towed underwater camera system. These were Baltimore, 

 Lydonia and Oceanographer Canyons. The depths surveyed were 

 100 to 1100 meters in Baltimore Canyon, 100-900 meters in 



