g. Rhodymenia-Veleroa Association . 



On the east side, an association exists which is signifi- 

 cantly depauperate in Lithothamnium complex and significantly en- 

 riched (relative to adjacent Lithothamnium associations) in the red 

 alga, Rhodymenia sp. This is the Rhodymenia-Veleroa association, 

 labeled G in Figs. 9 to 12. High densities of Veleroa complex, 

 ectoprocts, colonial anemones, corals, Serpulorbis sguamigerus , and 

 the densest growths of Dodecaceria fewkesi on the island are found 

 here. Nudibranches, especially Flabellinopsis iodinea, are also 

 common in this zone. The more fragile branching ectoprocts which 

 occur in deeper water on all four sides of the island exist at shallow 

 depths only on the east side, apparently because wave forces are much 

 reduced relative to the other three more exposed sides. 



h. Lithothamnium-Tetraclita Association . 



Above the Rhodymenia-Veleroa association (association G) on 

 the east side, an association composed almost entirely of Lithotham- 

 nium complex and the large thatched barnacle, Tetraclita squamosa 

 occurs over extensive shallow subtidal and intertidal areas (associ- 

 ation H in Figs. 9 to 12). Although the two species are found in 

 association in other parts of the island's intertidal and shallow sub- 

 tidal areas, these occurrences are very limited in extent. 



i. Diopatra-Cerianthid Anemones Association . 



Small pockets of shell talus, usually partially covered 

 with silt, are commonly found in the deeper areas of association F. 

 These areas are designated as association 1 in Figures 9 to 12, and 

 they extend over the talus beds to the natural bottom. The tube 

 worm, Diopatra ornata; tube anemones, Pachycerianthus spp.; bat 

 stars, Patiria miniata, and nudibranches (Dendrodoris fulva) are 

 very common in these associations. 



6. Gill Net Survey Results . 



Results of the gill net survey are summarized in Table 3. The 

 nets yielded a total of 270 fishes of 23 species. Five taxa ac- 

 counted for 61 percent of individuals captured. In decreasing order, 

 they were: olive rockfish, Sebastes serranoides ; midshipman, 

 Porichthys spp.; walleye surfperch, Hyperprosopon argenteum; swell 

 shark, Cephaloscy Ilium ventriosum; and white seaperch, Phanerodon 

 furcatus. Four of these species (all except C. ventriosum) were 

 captured on all four sides of the island. The highest number of 

 individuals and species was captured on the east (most protected) 

 side of the island. Average catch rates were highest during the day 

 on the west side, lowest on the east side. However, for the gill net 

 sets overlapping day and night periods, this pattern was reversed. 

 The south and east sides had the greatest number (15) of species in 

 common; the north and west sides were least similar in this respect. 



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