1. 



INTRODUCTION 



The canyon assessment study was divided into two parts. 

 The first part consisted of a historical survey of the epi- 

 benthic fauna, with particular emphasis on corals, found off 

 the coast of the northeastern United States. The data for 

 this first part was mainly collected from photographs taken 

 during previous dives of the submersible ALVIN. A detailed 

 examination of the coral and epibenthic fauna of three major 

 east coast submarine canyons was the objective of the second 

 part of this study. The canyons chosen for this study were 

 Baltimore, Oceanographer and Lydonia Canyons. By systematic- 

 ally classifying the faunal assemblages inhabiting these 

 canyons it is hoped that possible "fragile" communities can 

 be identified and avoided to lessen the impact of future 

 resource development. The results of this survey can also be 

 utilized as part of a baseline index for future environmental 

 monitoring. 



Until recently relatively little has been known about the 

 fauna that inhabits major submarine canyon systems. Previous 

 studies have been limited to small or not deeply incised canyon 

 systems. One of these studies was further hampered by the fact 

 that the method used to study the epi fauna, benthic trawling, 

 does not adequately sample localities of high relief such as 

 are frequently found in canyons. Studies by Rowe and Menzies 



