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Fishery Bulletin 97(3), 1999 



habitat is suitable, one would expect more newly 

 settled California halibut and newly recruited barred 

 sand bass at sites nearest the entrance because they 

 are more likely to encounter these areas first. This 

 might be especially true for embayments where the 

 entrance is small, such as in Alamitos Bay, which 

 could enhance chances of individuals encountering 

 a shallow site nearest the mouth of the bay. 



It is also possible that the distribution patterns 

 we observed were due to active site selection. Dia- 

 mond turbot, whose larvae also occur in nearshore 

 waters (Barnettetal., 1984; Walker et al., 1987) and 

 are thus exposed to the same hydrodynamic pro- 

 cesses, were most abundant in the inner part of the 

 bay and least abundant nearest the mouth of the bay. 

 Kramer (1991b) also obtained opposite distribution 

 patterns for juvenile California halibut and diamond 

 turbot. Burke (1995) found that the distribution of 

 two newly settled flounders that immigrated to an 

 estuary were influenced by the availability of pre- 

 ferred prey types. Although we have no data on in- 

 vertebrate prey distributions among sites, it is pos- 

 sible that California halibut and diamond turbot also 

 select sites on the basis of availability of their pre- 

 ferred food items. Juvenile California halibut and 

 diamond turbot have very different diets: small ju- 

 venile California halibut feed mainly on small crus- 

 taceans (Haaker, 1975; Plummer et al., 1983; Allen, 

 1988; Drawbridge, 1990), whereas juvenile diamond 

 turbot feed mainly on polychaetes (Lane, 1975). As 

 halibut grow larger, they become more piscivorous 

 and gobies become an increasingly important part of 

 their diet (Allen, 1988; Drawbridge, 1990). This might 

 explain why we found relatively larger halibut at 

 Belmont Shore than at Bay Entrance because this 



area contained more arrow gobies and cheekspot 

 gobies. Inhabiting an area with preferred food items 

 might lead to accelerated growth rates, which may 

 be an advantage for reducing size-selective preda- 

 tion. Sogard (1992) found that winter flounder 

 iPleuronectes americanus) and tautog (Tautoga 

 onitis) were most abundant in estuarine areas that 

 supported faster growth rates. However, we can not 

 discount that larval supply may also be a factor be- 

 cause the spawning locations of diamond turbot are 

 not known. Lane (1975) suggested that spawning 

 takes place in or very near the outer harbor. This 

 area would be much closer than where halibut spawn, 

 and inner parts of the bay would be closer to eggs 

 and larvae. In addition, laboratory experiments in- 

 dicate that diamond turbot larvae are able to sur- 

 vive longer periods of starvation than halibut larvae 

 (Gadomski and Petersen, 1988). This may enable 

 diamond turbot larvae to remain in the water col- 

 umn longer and reach inner parts of the bay whereas 

 halibut larvae must settle earlier 



Barred sand bass may also actively select sites 

 within Alamitos Bay. However, the differences in 

 physical characteristics of eelgrass among sites ap- 

 peared not to affect the abundance of new recruits 

 and juveniles. Although Bay Entrance had signifi- 

 cantly more eelgrass shoots and longer blade lengths 

 than Belmont Shore, barred sand bass abundances 

 at the two sites were not significantly different. This 

 lack of difference suggests that the effect of seagrass 

 physical characteristics on fish abundance breaks 

 down over larger spatial scales. However, if barred 

 sand bass settle indiscriminately into the first eelgrass 

 bed encountered, we would have expected significantly 

 more individuals nearest the bay mouth. Sogard ( 1989) 



