FISHERY BULLETIN: VOL. 83, NO. 8 



When an adult and calf were both at the surface, 

 they were usually within one adult-length of each 

 other. Videotape sequences showed the mean 

 distance apart to be 0.61 adult whale lengths (SD = 

 0.564, n = 8, range = 0.1-1.5), or about 9 m. The 

 calves spent most of the time lying beside the adult, 

 and facing in the same direction as the adult. At 

 times, the calf strayed up to two whale lengths from 

 the adult, and then oriented toward the adult. While 

 the adult lay at the surface, the calf often submerged 

 near the belly of the adult with its tail close to the 

 adult's tail. This position is probably indicative of 

 nursing. The calf then often swam under the adult, 

 surfaced on the other side, respired one or two times, 

 and submerged again toward the adult's belly, alter- 

 nating sides with each surfacing. The calf also ap- 

 peared at times to rest, lying quietly on the back and 

 tail of the adult. 



Calves were sighted at similar frequencies in all 3 

 yr (Table 3). However, durations of surfacings by 

 calves were longer in 1982 than in 1980-81. Because 

 of this, calves accounted for 15% of whale-hours of 

 observation in 1982, but only 3% in 1981, and 4% in 

 1980 (Table 3). 



Calves Alone 



In 1982, calves spent almost 40% of their time at 

 the surface unaccompanied by an adult. This was 

 comparable with their behavior in 1981, but unlike 

 1980 when they were rarely seen alone. (Table 3). 



On 24 August 1981, we saw three calves separated 



from each other and from the closest adults by 100 m 

 to more than 300 m. It was, therefore, often not 

 possible to assign calves to particular females. The 

 nearest adults spent much time submerged, but the 

 calves remained stationary at the surface. At one 

 point, we videotaped an adult that surfaced 4.9 adult 

 lengths from a calf lying stationary at the surface. 

 During another videotaped sequence, an adult-calf 

 pair, 0.2 lengths apart, was separated from a lone 

 calf by 7.6 adult lengths. We suspect that the adults 

 were feeding in the water column while calves 

 waited at the surface. 



In 1982, we observed four lone calves at the sur- 

 face, on 18, 19, and 23 August, and on three of these 

 occasions we saw the calf rejoin its presumed 

 mother. On 18 August, a lone calf surfaced and 

 oriented straight toward an adult at a distance of 1 .6 

 km. When it came within 75 m of the adult, the adult 

 also began to swim rapidly toward the calf. During a 

 second incident on the same day, a calf and adult 

 swam rapidly toward each other from at least 300 m 

 distance. In both cases, the two dove simultaneously 

 after coming together. On 23 August 1982, an adult 

 surfaced 180 m from a lone calf, and the adult 

 oriented toward the calf. When the two whales were 

 ~ 120 m apart, the calf also oriented toward the 

 adult, but the adult was mainly responsible for clos- 

 ing the distance between them, as it swam at 

 medium speed toward the calf. When the two whales 

 were ^ 20 m apart, the calf dove and reappeared 18 

 s later, reoriented by 180°, lying to the right of the 

 adult, and facing in its direction. The calf then 



Table 3. — Calf sightings and observation time in 1980, 1981, and 

 1982. Only flights with behavioral observations are considered, 

 and both presumably undisturbed and potentially disturbed 

 periods are included. The number of sightings of calves is an 

 approximate count because multiple counts of the same calf 

 were possible in cases where the calf and its mother were not in- 

 dividually recognizable. 



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