made before the island's construction, but Brisby estimates from personal 

 observations and from discussions with others that the population was 

 restricted to: coelenterates (i.e., the radially symmetrical inverte- 

 brate animals such as corals, sea anemones, jellyfish, and hydroids) ; 

 crustaceans, primarily crabs; and echinoderms , such as starfish. Occa- 

 sional growths of giant kelp were also seen in the area. The fish 

 population included migratory sport fish, silversides, and turbots . 

 California gray whales, sea lions, and harbor seals passed through the 

 area, and there was also a substantial transient movement of birds 

 characteristic of the coastal environment. 



c. Postconstruction Biota - Brisby 's assessment of the greatly- 

 increased present biological population of the island area is set forth 

 in detail in his report, attached as an Appendix. It is summarized here. 



Brisby has identified 27 species of algae including all three major 

 types (red, brown, and green). These are primarily restricted to the 

 region above the 30-foot depth, and the greatest variety is found in the 

 upper 10 feet. The larger stands of algae are destroyed by winter storms 

 but a rapid regrowth occurs in late spring and summer. The algae provide 

 both a food supply and a habitat for many of the marine organisms. 

 Brisby lists 10 major Phyla of fauna: 



1. Porifera . Over 24 species of sponges have been observed, of 

 which 14 have been identified. 



2. Coelenterate s. These form one of the most diverse groups of 

 organisms on the island. At least 19 species have been identified, and 

 possibly others might be found in the deeper recesses of the armor rock 

 surface. 



3. Platyhelminthes . The flatworms are present in large nxombers. 

 Brisby has tentatively identified four species. 



4. Nemertea . Several ribbon worms have been observed, but none 

 has yet been identified as to species. 



5. Annelida . These worms are common, generally large, and 

 therefore comparatively easy to classify. There are probably many more 

 species present than the 10 which have been identified. 



6. Arthropoda. Arthropods, the invertebrate animals with arti- 

 culate body and limbs (crabs, barnacles, lobsters, and shrimp) are present 

 in abundance and diversity. Brisby lists 21 species that have been identi- 

 fied. He also notes that their presence in such numbers indicates that oil 

 spills and contamination are not occurring at the island, since these 

 animals are particularly sensitive to hydrocarbons. 



7. Mollusks . Brisby notes that of the fauna, the mollusks have 

 experienced probably the greatest increase in numbers. He identifies 61 

 species, representing four classes of mollusks, with gastropods and 



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