SKIN, SHAPE AND FINS Humpbacks come in 4 different color schemes, ranging from white to gray to black to mottled.
There are distinctive patches of white on underside of the flukes (tail). These markings are unique to each individual whale,
like a fingerprint. The humpback's skin is frequently scarred and may have patches covered with barnacles.
Humpbacks have huge, mottled white flippers with rough edges that are up to one-third of its body length; these are the
largest flippers of any whale. The humpback's genus, Megaptera, means "huge-wings," referring to its flippers. The flippers
may have barnacles growing on them. The deeply-notched flukes (tail) are up to 12 feet (3.7 m) wide. Humpbacks have a small
dorsal fin toward the flukes.
DIET AND BALEEN Humpback whales (like all baleen whales) are seasonal feeders and carnivores that filter feed tiny
crustaceans (krill - mainly Euphausia superba, copepods, etc.), plankton, and small fish (including herring, mackerel, capelin,
and sandeel) from the water. They are gulpers (not skimmers), filter feeders that alternatively swim then gulp a mouthful
of plankton or fish. The species feeds only in summer and lives off fat reserves during winter. It is an energetic feeder.
It will hunt fish by direct attack or by stunning them by hitting the water with its flippers or flukes. Concentrated masses
of prey are preferable for this method of feeding. An average-sized humpback whale will eat 4,400-5,500 pounds (2000-2500
kg) of plankton, krill and small, schooling fish each day during the feeding season in cold waters (about 120 days). They
eat twice a day.
Humpbacks cooperate in hunting and have developed a method of rounding up highly concentrated masses of prey that is called
bubble-net feeding. The hunting members of a pod form a circle 10-100 feet (3.1-31 m) across and about 50 feet (15 m) under
the water. Then the humpbacks blow a wall of bubbles as they swim to the surface in a spiral path. The cylindrical wall of
bubbles makes the trapped krill, plankton, and/or small fish move to the surface of the water in a giant, concentrated mass.
The humpbacks then eat a large, hearty meal.
The humpback whale has about 330 pairs of dark gray baleen plates with coarse gray bristles hanging from the jaws. They
are about 25 inches (0.6 m) long and 13.5 inches (34 cm) wide.
DIVING, BREACHING, SPYHOPPING, AND LOBTAILING Humpback whales can dive for up to 30 minutes, but usually last only
up to 15 minutes. Humpbacks can dive to a depth of 500-700 feet (150-210 m).
Humpbacks are very acrobatic, often breaching high out of the water and then slapping the water as they come back down.
Sometimes they twirl around while breaching. Breaching may be purely for play or may be used to loosen skin parasites or have
some social meaning.
Spyhopping is another humpback activity in which the whale pokes its head out of the water for up to 30 seconds to take
a look around.
Humpbacks also stick their tail out of the water into the air, swing it around, and then slap it on the water's surface;
this is called lobtailing. It makes a very loud sound. The meaning or purpose of lobtailing is unknown, but may be done as
a warning to the rest of the pod. Humpbacks lobtail more when the seas are rough and stormy. Slapping a fin against the surface
of the water is another unexplained humpback activity.
MIGRATION Humpback whales take long seasonal migrations. They mate and calve in tropical waters during the winter
and then travel to cold polar waters during the summer to feed. During the summer in the warm waters, adults do not eat, but
live off their ayer of blubber (fat); the young calves feed on rich mother's milk.
Humpbacks migrate at 3-9 mph (4.8-14 kph). They have incredible powers of endurance, traveling over 3,100 miles (5000 km)
during each seasonal migration with almost no rest along the way. During migrations, they cover over 1,000 miles per month.
For more whale watching information go to California Whale Adventures
About the Author
This author runs a Whale Watching tour business called California Whale Adventures, out of San Francisco's Fisherman's
Warf. For information on whale watching tours call 415 760 8613
