Behavior 
In the first experiment, the recovered oil level in the exposure tanks waj 
about 0.08 ppm total hydrocarbon. The temperature gradually rose from 22° 
to 24.5° C over the 15-day experimental period. Behavioral changes were 
observed in the morning alert times, which, when comparing oil-exposed days 
with pre-exposure days, slowed in experimental animals (p < 0.05). Total food 
localization time was also slower (p < 0.025), perhaps as a result of slower 
alerting. Control animal behavior did not change (Table 10-1). In this first 
experiment, defensive postures and sometimes erratic and frantic behavior was 
observed in most of the exposed lobsters, and not in control animals. Defensive 
postures are characterized by wide open seizer claws, held close to the body, 
while the animal sits retreated far into its shelter. Erratic and frantic 
movements are sudden, unprovoked seizer snapping, jerky body movements 
and twitches. 
In the second experiment, the recovered oil level was about 0.15 ppm; 
temperature was a constant 10° C. Neither oil-exposed nor control animals 
showed significant changes in feeding behavior in the morning obervation, 
when comparing pre-oil with oil exposure period. In the afternoon observation, 
oil-exposed animals did not change their search speed but their alert was 
delayed (p < 0.05). Control animals had a faster search time in the afternoon 
(p < 0.005). Both control (p < 0.01) and experimental animals (p < 0.05) 
showed shorter wait times (Table 10-1). 
In the third experiment the temperature rose from 11° to 13.5° C, and the 
recovered oil level was 1.5 ppm. At 30 hours the lobsters showed gross 
neuromuscular defects, and oil inflow was stopped. In this experiment, 
behavior in post-exposure recovery period was compared with pre-exposure 
behavior. Experimental lobsters were slower in all phases of feeding behavior 
during the five-day recovery period than in the five-day pre-oil period 
(p < 0 .001). Even five days after exposure to 1.5 ppm #2 fuel oil for 30 hours, 
half the lobsters did not feed within the 10-minute limit (Figure 10-3). Control 
lobsters showed no significant differences (Table 10-1). The animals during this 
last experiment showed three levels of effects, some animals being affected 
much more than others. A description of the tliree levels follows (see also 
Figure 10-3). 
• Most extreme (two lobsters) —After 30 hours of oil exposure, these 
lobsters were found outside their burrows lying on their backs, pleopods 
twitching or still, tail half curled, walking legs twitching, antennae and 
antennules limp, gill bailers moving slightly. Occasionally the back and tail 
were arched and then curled. At times, attempts were made to right itself. 
Body jerked after food entered into tank. No recovery occurred in five 
days. 
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