Weinrich et al : Behavior of Megaptera novaeangliae during biopsy 



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responses in respiratory variables, we examined sep- 

 arately those animals that reacted to the biopsy strike 

 with an immediate hard tail flick (n 9), the most ob- 

 viously forceful immediate response to the biopsy 

 strike. This subset would therefore eliminate those 

 animals who may have not been affected by the biopsy 

 strike. However, variation among individuals during 

 the postbiopsy period was not appreciably different 

 from that portion of the sample where no hard tail flick 

 was observed (binomial test). Hence, the occurrence of 

 an immediate forceful response to the biopsy procedure 

 does not appear to be associated with subsequent 

 changes in respiratory variables. 



Net movement rate 



For 11 of the 21 animals, LORAN-C fixes allowed a 

 calculation of the animal's net movement rate in pre- 

 and postbiopsy focal samples. During the prebiopsy 

 sample, only two animals showed values > 1 kn. Dur- 

 ing the postbiopsy period, the average rate did not 

 increase significantly (Wilcoxon signed rank test, 

 Z -1.82, p 0.07). However, only three animals had 

 rates <lkn, and a generally increasing trend was 

 recorded (Table 7). 



Other behavioral responses 



To consider changes in behavior elicited by the biopsy 

 procedure, the possibilities of introducing new behav- 



iors or altering display rates of regularly observed 

 behaviors were both considered. The former was exam- 

 ined using the number of pre- and postbiopsy focal 

 samples during which each behavior type was observed, 

 while the latter was examined using the direction and 

 magnitude of changes in observed behavior types 

 within individual paired samples (Tables 8, 9). Only one 

 of the 30 tested behavior types showed significant dif- 

 ferences between the pre- and postbiopsy period. 



Eleven of the 21 (52.3%) postbiopsy focal samples 

 contained a hard tail flick, while the behavior was not 

 observed in the prebiopsy focal samples (binomial 

 distribution, p<0.001). Only once was a hard tail flick 

 observed more than one time after a biopsy strike. This 

 also was the only case in which the hard tail flick was 

 not an immediate response to the biopsy dart. The 

 percentage of biopsy strikes where the reaction in- 

 cluded a hard tail flick among paired samples was not 

 significantly different from that of the larger 1983-84 

 sample, where 34 of 50 animals displayed the hard tail 

 flick (x" 1.54, 1 df, p 0.21). 



As was the case in the number of 30-min samples in 

 which a behavior was displayed, only hard tail flicks 

 showed a significant increase in frequency during 

 the postbiopsy period (binomial distribution, p 0.001). 

 While results were not significant, one or more animals 

 also showed notable increases in the numbers of 

 trumpet blows, tail slashes, and belly-up lobtails follow- 

 ing the biopsy procedure; similar nonsignificant but 

 notable decreases were seen in back rises, tail rises, 

 and low head-ups (Tables 8, 9). The latter three 

 behaviors are associated with slow, unhurried travel, 

 resting, or interest in nonessential environmental 

 stimuli (e.g., boats, seaweed). 



