8. Gill Net Survey . 



A gill net survey was conducted on 15 and 16 June 1977. A 

 single multimesh nylon monofilament net, 30.5 meters long and 2.4 

 meters deep, was deployed obliquely along each cardinal side of the 

 island (Fig. 3). The nets consisted of ten 3.05-meter-long panels 

 with two panels each of 1.27-, 2.54-, 3. 81-, 5. 08-, and 6.35-centi- 

 meter bar mesh. Position of these panels in the net was random. 

 When deployed, the nets extended from the intertidal zone of the 

 island to the toe of the island revetment. The nets were fished for 

 two periods: a daytime period of about 4 hours, and a day-night 

 period ranging from a minimum of 17 hours (west side) to a maximum of 

 23.5 hours (east side). 



Fishes caught in each net were removed and identified, and a 

 record was made of the standard length (snout to distal end of caudal 

 peduncle) for bony fishes and total length (snout to end of caudal 

 fin) for sharks. Lengths were recorded to the nearest 0.5 centi- 

 meter. Numbers of individuals occurring in each mesh size were also 

 recorded. Summary data tables were prepared listing numbers of indi- 

 viduals, mean length, and length range for each species captured on 

 each side of the island. 



V. RESULTS AND DISCUSSION 



1. General . 



A total of 330 species of macrobiota was identified during this 

 study; 160 of these taxa had not been reported as occurring at Rincon 

 Island. This addition to the number of species reported in Keith and 

 Skjei (1974) brings the total species list to 458. Many additional 

 species undoubtedly exist among the island's varied habitats. An up- 

 dated master list of taxa of Rincon Island is given in Table 1. 



2. Volume and Dimensions of Talus Beds . 



Dimensions of the shell talus beds along each of the four cardi- 

 nal sides are shown in perspective view in Figures 5 to 8 and in plan 

 view in Figures 9 to 12, (The upper boundaries of the talus beds do 

 not match precisely with the lower boundaries of the deepest associ- 

 ations in these figures for two reasons: First, talus bed measurements 

 were taken at positions of change of the talus bed geometry, while 

 associations were measured along fixed transects; second, the deepest 

 association frequently extended into the talus bed on isolated rocks.) 

 Approximate volumes of shell calculated from the measurement of 

 talus bed dimensions are as follows: 



West side: 1^450 cubic meters 

 South side: 98 cubic meters 



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