1 get into the specifics of these, because they are all, probably to some 



2 extent, available to you. You've seen them before, and time this 



3 morning really doesn't permit. 



4 I'm sure that we will be getting into the discussion of some of 



5 these specifics through panel sessions later on, especially tomorrow. 



6 At this time, I'm going to just generically summarize the findings 



7 of these 12 years of submarine canyon studies, primarily from the point 



8 of view of the Georges Bank canyons, Lydonia, Oceanographer, and Veatch, 



9 and show you, as I mentioned, the short video tape. 



10 Several summary comments I'd like to make. Submarine canyon heads 



11 are unique physical features, that through physical and biological 



12 processes present a wide range of low relief, three-dimensional habitats 



13 that attract and/or support a megabenthic fauna whose species diversity 



14 and abundance greatly exceeds adjacent non-canyon areas of the outer 



15 shelf, upper slope environments. 



16 A major reason for these three-dimensional habitats having been 



17 maintained as well, relatively speaking, as they have in recent years, 



18 certainly is the inaccessibility of canyon-head environments to mobile 



19 fishing gear, i.e., trawls and dredges. 



20 I can't imagine an impact any more devastating than trawls and 



21 dredges would be to these submarine canyon-head environments, having 



22 seen over the years what similar gear does to comparable environments in 



23 our inshore areas. 



24 Species abundance and community structure of the megabenthos is 



25 very much a function of surficial substrate characteristics. The so- 



26 called habitat types, as we've defined them in past years, habitat types 



27 1 through 5, vary considerably in most of the canyons--Welcker and Block 



28 are exceptions. 



29 Along a given depth contour and across depth contours, patch size 



30 of a given habitat type and the associated fauna, can be as small as a 



31 few meters and as large as several kilometers. In other words, these 



32 submarine canyon-head environments are "^ery heterogeneous areas in terms 



33 of habitat types, and therefore, their associated megabenthic fauna. 



11 



