FISHERY BULLETIN: VOL. 83, NO. 3 





SANTA. BARBARA 



Figure 1 . - Location and block numbers of sampling sites about the northern Channel Islands, C A. 



boat at the beginning of the trip and remained 

 aboard, measuring and identifying all fish caught by 

 the passengers, until the boat returned to dock. A 

 particular effort was made to measure every fish 

 landed, even those returned alive to the water 

 because of undesirability or in compliance with bag 

 or size limit regulations. Also noted were the number 

 of anglers aboard the vessel, the hours of fishing, and 

 the location and depth of fishing effort. 



Each fish was placed on a plastic measuring sheet 

 held in a two-sided aluminum frame and the length 

 marked. Total length (tip of snout to tip of depressed 

 caudal fin) was recorded for all fish except members 

 of the jack (Carangidae) and mackerel (Scombridae) 

 families, from which fork length was taken. 



A portion of the caudal fin was clipped from each 

 fish measured so that the fish could be recognized 

 later. When fish were brought aboard too rapidly for 

 all to be measured, samplers gave immediate priority 

 to those being returned to the water and measured 

 the remaining fish at the end of fishing or during a 

 break in activity. When samplers were uncertain of 

 the identification of a fish, they retained it for 

 positive identification. After completing a trip, the 

 samplers tallied and recorded by species the data col- 

 lected. Individual fish lengths were measured on the 

 plastic sheet with a meter stick. 



The California Department of Fish and Game has 

 divided marine waters off California into numbered 

 blocks. For this study, we utilized data from block 

 numbers 684-690 and 707-712 (Fig. 1). Care was 

 taken to remove data from mainland fishing sites in 

 block number 684. Block 710 was Santa Rosa Island 

 alone. 



We measured fish abundances by catch per unit 

 effort, which was defined as number of fish taken per 

 angler hours (where angler hours = number of 

 anglers x number of hours fished). 



RESULTS 



One hundred and nineteen trips were made, and 

 the catches from 3,712 anglers were sampled. A 

 total of 23,089 fishes of 78 species were tallied, of 

 which 49 are listed in Table 1. Rockfishes (particu- 

 larly bocaccio, Sebastes paucispinis; blue rockfish, S. 

 mystimcs; and olive rockfish, 5. serranoides) and 

 kelp bass, Paralabrax clathratus, were numerically 

 dominant. Among the 20 most abundant species, 

 only 4 {Paralabrajc clathratus; chub mackerel. Scom- 

 ber japonictts; lingcod, Ophiodon elongatus; ocean 

 whitefish, Caulolatiliis princeps) were not rock- 

 fishes. 



We stratified our data by depth (36 m intervals). 



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