APPENDIX 



THE BIOTA OF RINCON ISLAND 



by 



William L. Brisby 



Professor of Marine Biology 



Moorpark College 



Moorpark, California 



I. PRECONSTRUCTION BIOTA 



Rincon Island was constructed on a sand-silt substrate with relatively 

 little biota present. These soft sediments eliminated, to a large extent, 

 those organisms which are commonly found in reef areas and, except for a 

 few exposed rocks, provided no basis for attachment of sessile organisms. 



The in- and epi-fauna consisted primarily of coelenterates such as 

 Stytatuta elongata, Ceriantheopsis sp., and Vadhycevianthus sp., crustaceans 

 of the genus Canoev , and echinoderms , primarily Astvo'peoten armatus , Patiria 

 miniata, and Paras tiehopus sp. Occasional growths of Maarooystis sp. came 

 to the surface from the few rock outcroppings on the bottom. 



The pelagic organisms were mostly transients, with the exception of 

 silversides and turbots which might be considered resident forms. Transient 

 vertebrates included many of the migratory sportfish and the three major 

 mammals, Zatophus oalifovnianus , Fhoca vitulina, and Esohriahtius glaueus. 



The information on the biota of the area before construction is not 

 complete as no organized study of this parameter was undertaken. The infor- 

 mation in this report is from personal observation and from discussions with 

 sportsmen and the California Department of Fish and Game. Undoubtedly there 

 were other forms of life present that are not listed here, but the area can 

 be called a "biological desert" and the listing here simply is to indicate 

 this sparsity of life. 



II. POSTCONSTRUCTION BIOTA 



With the construction of Rincon Island a new environment was esta- 

 blished with a great number of hard surfaces for the attachment of various 

 organisms. The placement of the large slabs of quarry rock and tetrapods 

 provided additional positive components to the environment by providing 

 crevices and caves into which various animals could retreat for protection 

 from both current and enemies. The sand-silt bottom still has an effect 

 upon the island, however, as the turbidity currents continually carry the 

 benthic sediments up onto the base structure to a height of approximately 



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