Whales at Table 
Text and photographs by James W. Greenough 
Banqueting in the cold waters off Alaska, humpback 
whales lunge at their prey with mouths agape 
Although not a biologist by educa- 
tion, I am a scientist of sorts — and an 
inveterate observer of wildlife. I am 
especially excited by great whales, even 
though I see them routinely while run- 
ning my commercial fishing boat. So 
when the opportunity arose to spend 
some time watching a group of hump- 
back whales in southeast Alaska during 
late November and December 1980, 1 
didn’t turn it down. One late fall morn- 
ing I transported John and Jan Straley 
of Sitka, Alaska, two whale observer 
friends, to their chosen bay off Admi- 
ralty Island. 
Well known among whale watchers as 
the most acrobatic of the great whales, 
the humpback leaps into the air more 
than any other species. Nearly everyone 
interested in whales has heard of or seen 
the dramatic breaches of the hump- 
back, in which thirty or forty tons of 
bulbous flesh erupt from the sea. Yet 
the humpback’s most dramatic behavior 
may well be its eating habits. The huge 
humpbacks (regularly about forty feet 
in length and occasionally over fifty 
feet) feed on a variety of tiny to small 
organisms, the largest of which is usu- 
ally the herring (sometimes up to ten or 
twelve inches, more commonly six 
inches). Needless to say, it takes a great 
many herring to feed one humpback 
whale. Specialized techniques are re- 
quired to round up and capture such 
quantities of fish. The techniques that 
humpbacks have evolved are both spec- 
tacular and complex. 
For three weeks we watched a group 
of twelve to fourteen whales surface 
feed continually during daylight hours. 
We were intrigued because it is not 
common lyiowledge that some hump- 
backs remain in Alaskan waters and 
continue to feed so late in the season. 
With the coming of cold weather and 
short daylight hours, the humpbacks 
generally head for warm tropical waters 
where they mate and rest, but do not 
feed. Indeed, most humpbacks had de- 
parted Alaskan waters by November, 
but for some reason these errant whales 
were still actively feeding in early De- 
cember. 
Humpbacks sometimes feed well be- 
low the surface in moderately deep wa- 
ters, but the type of feeding we watched, 
known as “vertical lunge” feeding, was 
done at the surface. The process, as 
performed by one whale, is simple. The 
whale sounds (dives), locates a school of 
herring (or a dense concentration of tiny 
organisms such as krill and plankton), 
then lunges upward through the prey, 
mouth agape. In this way it fills its 
gullet with herring and seawater. The 
gullet becomes greatly distended, ex- 
panding along the longitudinal pleats in 
the whale’s ventral surface. The whale’s 
mouth closes tightly, and then, with its 
huge tongue, it forces seawater out 
through its mesh of baleen while retain- 
ing the herring. 
A variation is the “horizontal lunge,” 
in which the whale pursues its food 
across the surface of the water. Horizon- 
tal lunges are made with the whale in 
virtually any orientation. At times the 
whale is on its side, often with one 
flipper out of the water, the lateral sur- 
faces of both upper and lower jaw ex- 
posed. At other times its dorsal surface 
and upper jaw are exposed in a posture 
reminiscent of a crocodile on the ram- 
page. Or the whale may be completely 
overturned, its pleated ventral surface 
and cavernous lower jaw protruding 
from the sea. Between the vertical and 
horizontal lunges there is a full range of 
possible angles in relationship to the 
sea’s surface. 
Lunge feeding in a single whale is 
dramatic enough, but when six or seven 
of these huge mammals lunge in a co- 
ordinated effort, the effect is stunning. 
Such group feeding seems more com- 
mon than lunge feeding by individual 
whales, and we rarely saw fewer than 
three participate in a lunge. The maxi- 
mum number we observed was seven. 
When such a group of whales feed 
together, it is not a loose association. 
Often the whales seem to be actually 
touching each other, so tightly are they 
grouped. The entire variety of lunge 
patterns was regularly observed in a 
single group lunge. Lateral, ventral, and 
dorsal surfaces of horizontally lunging 
whales, interspersed by one or two 
whales clearing the surface in vertical 
lunges, were a common sight. To see 
seven whales (weighing a total of per- 
haps 250 tons) erupt within a fifty- or 
seventy-foot circle, their lunges timed 
within a second or two, is awesome. 
Even more to the point, it suggests a 
respectable ability to communicate and 
coordinate actions. 
Almost as fascinating are the ways 
humpbacks prepare for feeding. Or, to 
be more objective, how they increase 
concentrations of the prey before ex- 
pending energy lunging. Bubble-net 
feeding is the most sophisticated 
method humpbacks employ to optimize 
food concentrations. One or two whales 
swim upward from below the prey in a 
closing spiral, blowing a constant stream 
of bubbles. The bubbles rise faster than 
the whales and form an ever narrower 
net around the trapped fish. The her- 
ring, following their instinct to flee from 
anything flashing in the water, swim 
away from the bubbles and gather at the 
center of the bubble-net. The whales 
then lunge upward, filling their gullets 
with seawater and herring. It has been 
reported that whales may vary the size 
of the bubbles in the net to suit the type 
of prey — small bubbles for tiny fish and 
large ones for larger fish such as herring. 
Bubble-net feeding has also been re- 
ported with plankton and other pas- 
sively drifting prey. 
No visible behavior of the whales can 
match the bubble-net for subtlety. On 
A humpback whale breaches the 
water off Admiralty Island, Alaska. 
30 
