Author index of volume 130

Abstract

Juvenile spot (Leiostomus xanthurus Lacépède) feed by obtaining sediment and manipulating it in its buccal cavity to remove meiobenthic prey. As meiofaunal densities increase, spot increase their number of feeding strikes and manipulation (processing) time. We used these behaviors to determine the effects of sediment contaminated with polycyclic aromatic hydrocarbons (PAH) on the ability of spot to use meiofauna as prey. Laboratory experiments were conducted with produced-water (at 22 mg PAH kg−1 dry sediment) and diesel-contaminated (at 122 mg PAH kg−1 dry sediment) sediments. In an avoidance experiment (at 22 ppm PAH), spot were allowed to choose between contaminated and uncontaminated sediment in the same aquarium to determine if they were capable of detecting and avoiding PAH. Based on the location and pattern of feeding strikes, spot did not avoid contaminated sediments. Two selectivity experiments were conducted to determine whether sediment-bound PAH interfere with spot's ability to locate and utilize high-density patches of meiofauna. In sediments contaminated at 22 ppm PAH, significant differences were found among meiofauna densities in mean per-strike processing times. Cumulative processing time (a function of per-strike processing time and the number of strikes) was not affected by 22 ppm PAH. Burrowing avoidance by meiofauna may have contributed to a non-significant increase in feeding strikes in contaminated sediment. At 122 ppm PAH, cumulative processing time significantly decreased in contaminated sediments due to decreased feeding strikes. Seven out of ten fish stopped feeding before the end of 30 min feeding trials, probably due to a narcotic effect of PAH released into the water column as sediments were resuspended during feeding. Spot did not alter feeding behavior at moderate–high PAH concentrations, which puts them at risk for both sublethal and lethal effects – immune-system suppression, reduced growth, endocrine disorders, fin erosion, skin lesions, cataracts, and ultimately death.