4. Distribution of Major Species Associations . 



Dendograms resulting from the computer analysis are presented 

 in Appendix C. The species groups identified by the computer generally 

 agreed with the field observations. Clusters are particularly distinct 

 for intertidal associations, as might be expected. On the basis of 

 this exercise and first-hand field observations, the following 13 

 species associations (not including the shell talus beds) were tenta- 

 tively identified and designated with generic names of conspicuously 

 dominant species: 



a. Diopatra/cerianthid anemones 



b. Astrangia/gorgonians 



c. Lagenipora/Scrupocellaria 



d. Lithothamnium complex/ Serpulorbis/Veleroa 



e. Macrophytic algae 



f. Mytllus/Pollicipes 



g. Barnacles/limpets 



h. Corynactls/Astrangla 



i. Lithothamnium com-plex/Serpulorbis/Dodecaceria/Veleroa 



j . Astrangia/Corynactis/Lophogorgia 



k. Tetraclita/Lithothamnium complex 



1 . Lithothamnium/Lagenipora/Veleroa 



m. Lophogorgia/Corynactis/Veleroa 



The results of the fieldwork which entailed charting of the bound- 

 aries of these preliminary or tentatively identified associations rela- 

 tive to permanent features on the island are shown in Appendix C (Figs. 

 C-3 to C-6) . The scale on each of these charts may be used to determine 

 plan view distances and actual (i.e., measured down the slope of each 

 side) distances of all association boundaries from permanent features 

 on the island. Permanent features include: navigational warning 

 devices, surveyor triangulation points, and corners of concrete 

 planter boxes used for landscaping the island. 



Over most transects, boundaries between associations were distinct. 

 Certain areas which appeared to have characteristics in common with 

 adjacent associations are labeled "transition" zones in the charts. 

 The intertidal associations 5, 6, 7, and 11 were particularly dis- 

 tinct. They contained species not found in other associations, their 

 boundaries were sharply defined, and they were generally much nar- 

 rower than the remaining (subtidal) associations. Associations 4 and 

 9, characterized by heavy coverages of Lithothamnium complex, accounted 

 for the largest subtidal area of the island. 



The east (protected) side differs in the general pattern of as- 

 sociations from the other three (more exposed) sides. Over most of the 

 east side, sea cucumbers (Parastichopus) , gorgonians (Muricea, 

 Lophogorgia) , stony corals (Astrangia, Paracyathus ) , and ectoprocts 

 (Lagenipora, Scrupocellaria) occurred in abundance. These groups were 



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