1 stations all look very different from each other, in spite of that 



2 dominance by Ampelisca at both the slope station and the fine sediment 



3 canyon station. 



4 At 550 meters we have one station in the canyon and one station in 



5 the slope. Again we see that the faunal dominance and composition was 



6 very different between the two. The same small polychaete, a seratulid 



7 called Tharyx baptistae was dominant at both stations, but again the 



8 percentages were very different. 



9 In the canyon, this one species accounted for 32 percent of all 



10 individuals collected at the station. At this particular depth, this is 



11 a most unusual result. You don't expect to find a community dominated 



12 to that extent by one particular species. 



13 The same species was dominant on the slope, but it accounted for 



14 only 6 percent of all the individuals at the station. 



15 In terms of looking at the top 20 dominant species and how many 



16 were dominant and were shared between the canyon and the slope station, 



17 we find that there were 5 of the 20 in common between the two. 



18 As we saw at 150 meters, the density/m^ is much higher in the 



19 canyon that on the slope. In fact, it's not quite doubled but it's 



20 getting there, 



21 In terms of diversity, this time the Shannon Index and Hobert 



22 Rarefaction Method gave us similar results, and that is that the canyon 



23 station had a lower diversity than the slope station. The Shannon 



24 values are 4.66 for the canyon and 6.0 for the slope. 



25 On this slide we see the Hobert Rarefaction curves. Station 4 is 



26 our slope station and station 7 is our canyon station. 



27 You can see that the curve for station 4 is almost identical to 



28 that for station 12, which was another station at 550 meters of water 



29 depth, but it was several kilometers distant from our Lydonia Canyon 



30 station pair. Just for reference this station 11 was at 225 meters on 



31 the slope. 



32 When we looked at similarity, we did look at all the stations in 



33 the program, but this particular slide examines only stations at 550 



34 meters, and unfortunately I forgot my colored pens or I would have 



122 



