Behavior 



In the first experiment, the recovered oil level in the exposure tanks was 

 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 tvdtches. 



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 three 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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