Diving 



The only right whale instrumented for depth dove deep routinely. The average dive 

 duration for individual right whales (86 s +/-48) varied between 54 - 162 s. The number 

 of dives varied from 9.2 to 153/hr. (x = 44.6/hr.). The variability in dive habits appears to 

 be real, making simple correction factors for aerial and ship surveys less likely. We believe 

 some of these differences were related to individual variability and environmental 

 circumstances rather than differences in sex, age, or behavior. Whale diving strategies 

 appeared to be most alike when they were swimming at "high"speeds (> lOkm/hr.) although 

 they were still not identical. We believe the relationship of average dive duration and 

 number of dives/hour during high speed swimming may approach an optimal aerobic 

 respiratory rate. 



Resting 



All whales spent time at the surface, but some more than others (range 13-33%). 

 Interestingly, the fastest animal (a female) spent the most time at the surface, with 69% of 

 all transmissions indicating surface resting. In contrast, a male spent less time surface resting 

 when he was traveling between breeding areas than when he settled into one area and was 

 presumably feeding. 



Effects of Tagging 



The 1989 attachment system was large, heavy, difficult to apply and not very effective. 

 The two-stage projectile sequence did not work well due to drag and turbulence. None of 

 the pole-deployed tags deployed in a completely satisfactory manner although one lasted 22 

 days and gave excellent dive depth information. 



We observed mixed reactions to the tagging process in 1989. None of the tags fully 

 deployed. One whale resumed sleeping almost immediately after tagging while two others 

 actively avoided the boat when we attempted to closely approach for follow-up observations. 

 Overall, 1989 responses were more than would have been expected by a close boat 

 approach. One whale tagged in 1989 was observed in 1990 at close range had a short 

 straight white scar were the tag had been. 



The transmitters in 1990 were greatly reduced in size and weight compared to those 

 used in 1989, although they no longer recorded depth data. The 1990 attachment system 

 worked well. The tags were easily applied and caused only mild reactions from a few 

 whales. Three whales were approached from 1-4 days after tagging with no more avoidance 

 response than untagged whales. While we did see some mild swelling shortly after tag 

 application on three animals in 1990, this was a normal and anticipated initial response to 

 the process. There appeared to be no long-term ill affects from tagging. Calves did not 



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