FISHERY BULLETIN: VOL. 75, NO. 1 



shallow water. Gilmore (1969), for one, reported 

 no aggression from unprovoked whales during his 

 work in the calving lagoons. We can lay these 

 suspicions to rest. Female gray whales separated 

 from their young are apt, indeed, to be vigorously 

 aggressive. But like Gilmore, we have never seen 

 aggression from unprovoked whales. Two exam- 

 ples from our field notes will suffice. 



During capture the female stays in close at- 

 tendance with the young, often placing herself 

 between the baby and the shore line party. She 

 sometimes pressed against the young, literally 

 yanking the line from line handlers. These 

 thrashings increased in intensity as the baby 

 neared the shelf and it is our opinion that the 

 mother was very dangerous at this time. We have 

 always taken care to work with the baby 20 m or so 

 into shallow water where the mother could not 

 come. She patrolled the shelf edge at this time in 

 water just deep enough to allow her passage and 

 she even partially stranded herself. When the 

 baby was taken into very shallow water or far over 

 a flat, the mother sometimes wandered away. We 

 presume this to indicate a loss of effective acoustic 

 communication. 



During one capture a line handler allowed 

 himself to come within a few meters of the shelf 

 beyond which the mother patrolled. She reared up, 

 swung her flukes laterally just at the water's edge, 

 with sufficient force that a sheet of water was sent 

 over the entire work party. The blow missed the 

 nearby line handler by a couple of meters but none 

 of us doubted that it would have done serious in- 

 jury if it had hit him. 



On another capture, a young animal was 

 stranded and the scientific party had worked on 

 harnessing the animal for perhaps 20 min when 

 the mother wandered away. The collection vessel 

 had been given the task of keeping the mother 

 close to the shore party by maneuvering around 

 her. The ship was standing by 1 km to the south 

 and about 0.5 km off the channel edge during 

 stranding and then moved up to within about 100 

 m of the shore party to herd the mother whale 

 while we harnessed the calf. The adult disap- 

 peared below the surface for about 45 s and came 

 up under the stern of the vessel, hitting the hull so 

 hard that the vessel was lifted up about a meter 

 and heeled over 25°-30° to starboard. The whale's 

 tail swung up in the air astern, with the broadside 

 of the flukes toward the ship and approximately 2 

 m of the tail extended above water. The captain 

 put the ship full speed ahead at about 12 knots and 



attempted to elude the whale. The whale followed 

 below the vessel and three times rose to hit it, 

 swinging her flukes up above water astern even 

 though in full chase. The vessel ran in broad cir- 

 cles and finally swung over fairly shallow water, 

 and at the same time threw seal bombs into the 

 water (firecrackers used to disperse sea lions from 

 fishing nets). The whale moved away at this point, 

 after a chase of 5 to 7 min. The ship was largely 

 undamaged except for a slightly bent propeller 

 blade. The captain felt that the fast maneuvering 

 prevented serious damage to the vessel. 



Phonation 



Evidence has been accumulating in recent years 

 that the gray whale produces a number of different 

 sound signals, including grunts, pulses, clicks, 

 moans, bubble-release sounds, knocks, and rasp- 

 ing pulses. These sound records have been re- 

 viewed by Poulter (1968) and by Fish et al. (1974), 

 and the latter workers recorded the sound of the 

 yearling captive gray whale Gigi. These authors 

 suggest that the metallic pulses recorded from 

 Gigi may have been associated with the internal 

 flow of air bubbles, since no air was released dur- 

 ing the sound emission. They also reported click 

 trains released by feeding gray whales, which 

 consisted of clicks with principal energy from 2 to 

 6 kHz and duration of 1.0-2.0 ms, with a click 

 repetition rate of 9.5 to 36.0/s. Similar click trains 

 have been recorded by us in the channel near 

 Lopez Mateos. In addition, we can directly attri- 

 bute two kinds of sounds in whale calves since both 

 were heard or recorded directly from these ani- 

 mals as they lay partially out of water; these were 

 repeated low pulses and a very loud bang or in- 

 tense click. 



Low resonant pulses, which were not recorded, 

 were emitted by a stranded calf on 27 January 

 1973 during harnessing. Each was a second or less 

 in duration, emitted each 2-3 s, and concurrent 

 with such emission one could see slight movement 

 of the animal's body surface behind the head on 

 the lateral body surfaces. No air was released 

 during emission. This young animal was emitting 

 pulses when reintroduced to the bay. The mother 

 had wandered off some 300 m down channel by 

 this time and as the baby swam across channel, 

 the mother was seen to throw her flukes twice and 

 then swim directly toward the distant baby. As 

 they met, the mother slashed the water rather 

 violently with her flukes, circled the baby and the 



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