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Fishery Bulletin 90(4), 1992 



relatively heavy settlement was observed throughout 

 the coastal area, as far north as Stn. 2. The greatest 

 numbers were taken off Stns. 2 (Refugio Beach), 6 

 (Ventura), 10 (Malibu), and 13 (Belmont Shore). None 

 were taken at Stn. 15 (Laguna Beach) where they were 

 most abundant a month earlier. In August, the number 

 of recently-settled white seabass had declined from the 

 July peak. Moderate numbers were captured at Stns. 

 7 (Hueneme), 11 (El Segundo), 13 (Belmont Shore), 

 and 15 (Laguna Beach). In September, young seabass 

 settled at the middle stations (stns. 6-11). By October, 

 no new settlement was detected at any of the study 

 sites (Fig. 5). The only YOY white seabass was an older 

 fish (78mmSL) taken at Stn. 16 (San Mateo Pt.). 



Sixty-three percent (170 individuals) of all YOY were 

 taken at the 5m depth in 1988. YOY white seabass 

 were most numerous at the 5 m isobath at Stns. 2-4, 

 10-13, and 15, but were more abundant at 10 m at Stns. 

 5-9 (Fig. 6). 



Analysis of variance of CPUE values in 1988 indi- 

 cated that only the observed monthly differences were 

 statistically significant (Table 1). Differences in CPUE 

 among stations and depths were not significant in 1988. 



YOY white seabass densities ranged from a low of 

 0.3 individuals/ha in October 1988, to a high of 37.8 in 

 July 1988. In 1988, population estimates varied great- 

 ly along the approximately 300km of coastline (ex- 

 cluding the offshore islands) covered in 1988. Overall 

 density for the 5-month period yielded a population 

 estimate of 130,000 individuals in the area of southern 

 California covered by the sampling. 



Summer 1989 Sampling from May to August 1989 

 along the coastlines of the mainland and the offshore 

 islands produced 85 YOY. The catch rate at the main- 



Figure 5 



Abundance of YOY white seabass A. nobilis by station over 

 the five months (June-October) of the 1988 survey. 



Figure 6 



CPUE of YOY white seabass A. nobilis by station and 

 depth for the 1988 survey. 



land stations was 15 times higher than at island sta- 

 tions (CPUE 0.59/tow in 128 tows vs. 0.04/tow in 240 

 tows) (Fig. 7). Most (88%) of the YOY were captured 

 at three of the mainland stations: Stns. 6 (Ventura, 

 n 22), 10 (Malibu, n 14), and 15 (Laguna Beach, n 38). 

 Five YOY were captured at Stns. 17 and 18 on Santa 

 Cruz I., four were taken at Stn. 22 (White's Cove) on 

 Santa Catalina I., and none were taken at Santa Rosa 

 or San Clemente I. 



The CPUE was low in May (0.14/tow), peaked in June 

 (0.45/tow), and declined through July-August (0.14/ 

 tow) (Fig. 8). Settlement was restricted to the southern 

 mainland stations (13 and 15) in May (Fig. 9). By June, 

 settlement was observed as far north as Stn. 6 (Ven- 

 tura) with the greatest numbers occurring off Stns. 10 

 (Malibu) and 15 (Laguna Beach). In July and August 

 settlement was highly variable at the mainland sta- 

 tions. The five YOY white seabass taken at Santa Cruz 

 I. (Stns. 17 and 18) were captured during June, July, 



