Lopez-Rasgado and Herzka: Assessment of habitat quality for juvenile Paralichthys cahfornicus 
353 
10 
8 
6 
4 
2 
0 
10 
8 
6 
i Outer 
i Central 
i Inner 
-o -o 
B 
ll S I a 1 1 1 1 I ■ 
i 1 1 i a 
Oct Jan Mar May Jun Sep 
Oct Jan Mar May Jun Sep 
Figure 6 
(A) Recent otolith growth rates of wild-caught juvenile California halibut ( Paralichthys 
californicus) sampled between October 2004 and October 2005. Different letters indicate 
significant differences. (B-E) Recent otolith and somatic growth rates of juveniles held 
in cages for either 14 (B, D) or 28 days (C, E). Values are means ±standard error (SE). 
Asterisks represent lost cages. 
tolerant species such as juvenile California halibut may 
utilize the entire embayment as juvenile habitat. 
Various studies have reported that small juvenile 
California halibut are found in higher densities in 
shallow habitats (~<2 m; Allen and Herbinson, 1990; 
Fodrie and Mendoza, 2006). This is consistent with 
our results; the highest densities of juveniles in Punta 
Banda Estuary occurred at depths between 1-2 m. 
To our knowledge there are no studies examining the 
causes of underlying the depth-related distribution pat- 
terns in juvenile California halibut, but size-specific 
depth preferences have been associated with resource 
partitioning, avoidance of predation by conspecifics, and 
feeding excursions into shallow areas (Kramer 1990; 
Gibson, 1994; Able et al., 2005). In addition, the use 
of shallower habitats subject to stronger variations in 
temperature by smaller juveniles is consistent with 
the higher tolerance of smaller juveniles reported by 
Madon (2002). 
The low proportion of the variance explained by the 
GLM analysis suggests other abiotic or biotic variables 
also influence juvenile density. The lack of a significant 
relationship between dissolved oxygen concentrations 
and density is probably due to the absence of low DO 
levels during our surveys; values <2 mg/L are typically 
associated with detrimental effects on growth and sur- 
vival of fishes (Stickney, 2000). Abundance of juvenile 
flatfish has been negatively related to sediment grain 
size, although the relationship varies among species and 
with size (e.g., Drawbridge, 1990; Amezcua and Nash, 
2001). This may be due to the influence of sediment 
grain size on prey availability, or related to the burial 
