(c) establish permanent transects on each side of the island 

 and survey major benthic organisms along these transects 

 on a seasonal basis, documenting changes in biotic compo- 

 sition and habitat character; and 



(d) conduct a gill net survey of the fish on each side of the 

 island; and 



(e) expand the existing species list of the area. 



II. PROJECT SETTING 



Rincon Island is located in the Santa Barbara Channel approxi- 

 mately midway between the cities of Santa Barbara and Ventura, 

 California. The island is about 0,8 kilometer off Punta Gorda in 

 about 14 meters of water, and is connected to the mainland by a 

 causeway (Fig. 1). The extreme tidal range at the island is 3.05 

 meters. Mean sea level (MSL) lies 0.79 meter above mean lower low 

 water (MLLW) . The island covers about 0.026 square kilometer of 

 ocean floor and the area above MLLW is approximately 0.013 square 

 kilometer. 



The island is constructed of rock revetments containing sandfill. 

 It was constructed in stages between February 1957 and September 

 1958, using many types and gradations of quarry rock. The most 

 exposed face (west side) is protected with 1,130 concrete tetrapods, 

 each weighing about 31,000 kilograms. The general shape of the is- 

 land and the local bathymetry are shown in Figure 2 (Dames § Moore, 

 1974) . Bottom conditions vary uniformly throughout the area (Blume 

 and Keith, 1959) . The sediment consists of siity sand ranging into 

 sandy silt with a thickness ranging from 4.3 to 7.6 meters. It 

 overlies a geologically recent shale or "siltstone" formation. 

 Average bottom slope is 3 percent. 



Details of the construction and engineering considerations in 

 the design of Rincon Island are summarized in Keith and Skjei (1974) 

 and Blume and Keith (1959). 



III. PREVIOUS RELATED STUDIES 



1. General Studies of Artificial Reef Habitat . 



The value of artificial structures for attracting marine fishes 

 was the subject of many papers presented at an International Arti- 

 ficial Reef Conference, cosponsored by Texas A^M University, the 

 Texas Coastal and Marine Council, and the National Marine Fisheries 

 Service (Colunga and Stone, 1974). The fish-attracting properties of 

 nearshore artificial reefs composed of tires, car bodies, and riprap 

 on the gulf and Atlantic coasts have been documented by Buchanan 

 (1972), Stone (1972, 1973); Stone, Buchanan, and Parker (1973); 

 and Stone, Buchanan, and Steimle (1974). The latter investigators 

 reported an increase in the fish-carrying capacity of an area 300 to 

 1,800 times that of the open bottom before reef construction. 



