The great convenience of access and supply provided by the causeway 

 has resulted in very little use of the wharf. A minor exception is that 

 following the 1968 Santa Barbara oil spill, the wharf was used by small 

 boats engaged in clean-up operations. This alternative to supplying clean- 

 up boats at Santa Barbara or Ventura resulted in a considerable savings in 

 time during these operations. 



9. Ecological Effects 



a. Study Procedure - Although Rincon Island was constructed for 

 other purposes, it was anticipated that the construction of armor revet- 

 ments on the island faces would furnish desirable habitats for marine 

 organisms, and thereby favorably alter the environment for marine biota 

 in the area. A study of this topic conducted by William L. Brisby, 

 Professor of Marine Biology at Moorpark College, Moorpark, California, was 

 undertaken for this report. Professor Brisby is particularly qualified 

 for this study because of his personal knowledge of the marine environment 

 prior to the island's construction, and because he has been conducting 

 detailed field studies of the same environment during the postconstruction 

 period, using the island as a field station. 



Brisby 's study consisted of observing and identifying marine organisms 

 on and near the island. The observation program was adjusted to accommodate 

 two major problems. The solution to the first of these, the obvious diffi- 

 culty posed by observation of an underwater environment, was the use of 

 scuba gear. Brisby estimates that 85 to 90 percent of all observations were 

 made using scuba. Most observations were conducted using the island as a 

 base. When it was not feasible to proceed with the scuba technique, sur- 

 face craft and mechanical collecting gear were used, including Peterson 

 grabs (a small clamshell), dredges, trawls, fishing gear, and traps. 



The second major impediment to the observation program was the fre- 

 quent underwater turbidity caused when fine-grained bottom sediments were 

 stirred by waves or currents. Visibility is severely restricted under 

 these conditions. Underwater lighting was tried, but was of little or no 

 help. The solution was to schedule observations for those times when the 

 area had been sufficiently calm long enough to allow most of the fine 

 materials to settle out. Brisby notes that turbulence tends to keep some 

 of this material in suspension, limiting average visibility to 1 to 2 feet 

 at the bottom and to about 8 feet at the surface. 



In addition to visual observation and identification, Brisby used 

 underwater color photography. The camera used was a Nikonos 2 with Ekta- 

 chrome film and flash lighting. 



b. Preconstruction Conditions - Brisby notes that prior to the 

 island's construction, the area supported only a sparse population of marine 

 organisms. This is generally attributable to the presence of a soft, fine- 

 grained bottom which to a large extent excluded reef -dwelling organisms 



and also provided no means of attachment for sessile or base-attached orga- 

 nisms. No organized study of the biological population of the area was 



47 



