RECOVERED OIL (PPM) 
EFFECT OF NO. 2 FUEL OIL ON 
LOBSTER FEEDING BEHAVIOR z o 
PRE OIL POST 
Figure 10-3. Effect of 1.5 ppm No. 2 Fuel Oil (WAF) 
on Lobster Feeding Behavior. 
NOTE: Large bars indicate number of lobsters not feeding within 10 minutes 
of food introduction. Broken line represents estimated oil levels in lobster 
tanks based on actual recovery measurements (indicated by dots and stand¬ 
ard deviation bars). Hatched horizontal bar shows period of oil introduction 
into the system. "Pre" is the 5 day pre-exposure period: all lobsters feed and 
recovered oil remains below 0.05 ppm. "Oil" is the exposure period: highest 
exposure level 1.7 ppm, oil stopped after 30 hrs. "Post" is the recovery per¬ 
iod: oil quickly leaves the system, feeding behavior remains seriously affected 
for the entire 5-day period. 
• Moderate (three lobsters) — These animals were generally out of their 
burrows in two alternating stances. In one, the tail and head were down, 
the antennae were folded back, the antennules beat slowly, and the 
animal lay down low on the walking legs. This appeared to be a resting 
position. Then the tail and head arched up, the claws were opened and 
held close to the body, the antennae and antennules were held straight up 
and together, animal stood high on walking legs, and made frequent tail 
flips. Poor coordination was exhibited. Frequent aggressive lunges were 
made with open, raised seizer claw, or jabs with both claws at no obvious 
target. Lobsters were unaware of the presence of food, at times walking 
right over it without responding. If they did pick up the food, they 
continued to wander aimlessly around the tank with the food clutched 
tightly in the maxillipeds. Recovery in five days was almost complete in 
two animals; one animal did not recover. 
• Light (one lobster) — This animal remained in its burrow but was high on 
its walking legs, “spider” position and shaking. There were sporadic alerts 
not necessarily related to food. It exhibited no search. After two days 
recovery, there were slow hesitant approaches to the food with tail flips at 
the slightest irregularity. At the end of five days there was complete 
recovery. 
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