In order to simulate an offshore oil spill event, we assessed the acute toxicity of the non-dispersed and the chemically dispersed water-accommodated fraction (WAF) of crude oil using Louisiana sweet crude and Corexit(®) 9500A with juvenile Harris mud crabs (Rhithropanopeus harrisii), an important Gulf of Mexico benthic crustacean. The chemical dispersion of crude oil significantly increased acute toxicity of the WAF in juvenile mud crabs compared to naturally dispersed oil. The majority of the mortality in the chemically dispersed treatments occurred within 24 h. While higher concentrations of chemically dispersed WAF had no survivors, at lower concentrations surviving juvenile crabs displayed no long-term effects. These results suggest that if the juvenile crabs survive initial exposure, acute exposure to dispersed or non-dispersed crude oil may not induce long-term effects.

No abstract

No abstract

Effects of feeding level and starvation on growth, water content and protein content were examined in juvenile Cherax quadricarinatus. Gain in body weight was positively related to feeding level. An increase in feeding level resulted in a decrease in water content and an increase in protein content. Although the majority of juveniles were able to tolerate starvation for at least 12 days, deprivation of feeding caused a loss of weight and a gradual decrease in protein content combined with a simultaneous increase in water content. Total protein content was reduced by 3.9% in juveniles starved for three days and by 8.3% in those starved for 12 days. Normal body protein content, however, was recovered within six days after subsequent feeding in juveniles that were deprived of food for 12 days.

No abstract