Habitat selection and utilization of white croaker (Genyonemus lineatus) in the Los Angeles and Long Beach Harbors and the development of predictive habitat use models.

ABSTRACT

White croaker (Genyonemus lineatus) are a sentinel fish species for contamination due to their direct interaction with contaminated sediments through benthic foraging. White croaker within the Los Angeles (LA) and Long Beach (LB) Harbor exhibited hierarchical habitat selection avoiding dredged areas while selecting for areas of high sediment total organic carbon (4.8-8.1%), high polychaete density (406-700 polychaetes/0.1 m(2)), and small sediment grain size (<23.5 µm). Model results suggest that these fish are moving into shallower waters at night, which may be to forage and refuge more during the day presumably to avoid predation. The predictive model for white croaker habitat use indicated three important areas of use within the LA-LB Harbor Consolidated Slip, Inner Long Beach Harbor, and Fish Harbor. The areas containing the most frequently selected habitats by white croaker are also often areas of high sediment contamination, and thus are likely locations where these fish are acquiring contaminants. While many sediment mitigation alternatives exist, identifying and remediating sediments in key white croaker habitat may lead to a decrease in white croaker tissue concentrations over time if the fish continue to utilize these areas post remediation.