attached to the upper (splash zone) marker stake and the other end 

 was attached to the center stake on the bottom. This ensured exami- 

 nation of the same area on each side during the four seasonal sur- 

 veys. Divers carrying 1- square meter quadrats, underwater clip- 

 boards, and plastic collecting bags swam the transect lines, re- 

 cording data on densities of all species of macrobiota (in duplicate 

 samples) at 1 -meter increments. 



Seasonal density values were recorded as percent of unit area 

 covered for algae and encrusting colonial animals or as number per 

 unit area for species for which individuals could be counted. Cer- 

 tain species (e.g., Serpulorbis sguamigerus , the scaled worm shell) 

 were recorded for both numbers of individuals and percent coverage. 

 Species of uncertain identity were collected, making notation of 

 the quadrat number from which they were collected, and later identi- 

 fied. Each transect was photographed using an underwater camera. 



The marker stakes remained intact during the entire year of sur- 

 vey. They were located on each sampling trip except one on the north 

 side of the island. Extreme water turbidity precluded attachment of 

 the transect line to the bottom marker. In this case, the transect 

 was repeated by placing the line on structures (including a submerged 

 pipeline) recognized from previous surveys. 



The same two diver biologists recorded the data on each seasonal 

 survey with the exception of the north side during the summer (August 

 1976) and the west side during the winter (February 1977) surveys, 

 when another diver was used. Heavy surf prevented collection of 

 complete data on the west-side transect during the fall (November 

 1976) and winter (February -March 1977) . Data were not collected in 

 the upper zone during either of these two seasons. 



All data were transcribed from the field sheets to data tables 

 which listed densities of both plants and animals in each quadrat. 

 Fifty-four of the more common species were analyzed for seasonal 

 abundance. Details of the methods used in the analyses of the perma- 

 nent transect data for significant seasonal differences in species 

 densities are provided in Subsection 2 of Appendix A. 



5. Mapping of Major Species Associations . 



The fourth subtask was to chart the distribution of major species 

 associations over all submerged parts of the island. A series of 

 charts was prepared depicting the boundaries of major species associ- 

 ations and the spatial disposition of these associations, accurate to 

 +0.2 meter in depth and +^0.3 meter in korizontal distance from perma- 

 nent reference points on the island. This phase of the work required 

 identification of faunal and floral associations on the basis of sub- 

 strate character and recurrent groups of species that were conspicu- 

 ous by virtue of size, abundance, or biomass. 



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