Effect of Sublethal Concentrations of Fuel Oil on the Behavior and Survival of Larvae and Adults of the Barnacle Balanus Amphitrite Amphitrite (Darwin)

The sublethal effect of petroleum hydrocarbons (fuel oil) was investigated using different developmental stages of Balanus amphitrite amphitrite. 5, 10, 15 and 20 ppm concentrations of the water soluble fraction of the fuel oil were applied and found to have significant effect on the behavior and survival of the organism. Larval stage II was more sensitive than the other stages and was affected even with the lowest concentration of hydrocarbons (5 ppm) . Nutritional activity of the adults was affected by fuel oils due to effects on the movements of the cirri as indicated by altering the number of cirri beats. At 15 and 20 ppm concentration, cirri stopped moving and the organisms died. Accumulation of the hydrocarbons in the organisms's tissues was determined and was highest at 15 ppm concentration (after 48 hours exposure time) where it reached 240 ig/g dry weight. After 96 hours of exposure only adults exposed to 5 ppm could be recovered. Due to continuous pollution in the study area, there always be petroleum hydrocarbons in the organisms tissue which reach 55 ig/g, but the barnacles can tolerate up to 100 ig/g.