It’s time again, time for the Humpbacks to begin their
annual migration through Caribbean waters on the trek to their summer feeding
grounds off the northeastern coast of the United
States and
Canada. Hopefully, a fortunate few
of us will see one as it passes by, perhaps a lone bull leading the way or,
luckier still, one of the mother and calf pairs that follow the bulls a few
weeks later.
Those of
us who do see one will be seeing one of the world’s most endangered
whales. Because they are relatively slow and stay close to the surface as well
as closer to shore than other species of whales, the Humpback was hunted to
near extinction throughout the world’s oceans where they once numbered in
the hundreds of thousands. Today, there are fewer than 12,000 worldwide with
approximately 3,000 remaining in the Atlantic.
Humpback
whales come to the Caribbean during the months
of January through March to breed and give birth in our waters; waters that are
warm but lack the rich nutrients upon which the Humpbacks feed. During the
three or so months they spend in the Caribbean,
they lose several hundred pounds.
At 30-60
feet in length, Humpbacks are actually one of the smaller whales, having a
rather stout body that can weigh up to 75 tons. They are Baleen whales, one of
the rorqual whales as are the Blues (the
largest mammal ever to exist on earth), Minke, Brydes, Sei, and Fin whales.
Humpbacks and other rorquals feed by scooping up huge
mouthfuls of sea water and then forcing it through as many as 30 baleen plates
where the krill, plankton, herring, and other fish are filtered out as the
water pours from the sides of the whales’ mouths.
All rorqual whales have a dorsal fin and, particularly, in
Humpbacks its shape and size varies greatly, giving scientists yet another way
to identify individuals. Humpbacks have very long, thin pectoral fins that
measure approximately 1/3 the entire length of the whale. A 50-foot long
Humpback will have graceful pectoral fins, each about 17 feet in length. Their
scientific name Megaptera novaeangliae translates to “Great Wings of New
England”.
Another
striking characteristic of Humpback whales is their tail fluke, which can reach
some 20 feet across. Their dorsal or upper body is black while their ventral
side or underside ranges from black to gray to white, and is often mottled. The
ventral coloring extends to the under surface of the fluke and each fluke
pattern is different. Because Humpbacks are considered the acrobats of the
whale world they often expose the underside of their tail flukes and the
individual patterns on those flukes allow for easy identification even from a
distance. Another physical characteristic allowing identification are the knobs
on the whales’ heads, known as tubercles from which hairs protrude. It is
believed that these hairs provide a sense of touch, since Humpbacks are very
tactile, especially with their young.
They
reach sexual maturity around the age of 9-10 years and breeding females deliver
a single calf every 2-3 years. Whales are air-breathing mammals so when the 15
foot, 5,000 pound calf is born, the mother must quickly nudge him toward the
surface for his first breath. Within 30 minutes of birth, the calves are
surfacing for breath and swimming on their own. They nurse from their mothers
for about a year before learning to eat solid food. They can live for up to 100
years, although many meet with early deaths due to entanglement in fishing
gear, collisions with boats, and still today, both illegal and legal whaling.
Humpback
whales are the only whales known to sing, developing long, melodious songs that
carry for many miles through the oceans. Since only the males sing, scientists
are relatively certain that the singing is to attract females. And, the songs
are individual to distinct populations based on locale. Those studying the
songs have witnessed songs changing with additions and deletions of passages
over time but the songs remain distinctive between populations.
So…if you are one of the fortunate few to see a Humpback as it
travels north this year, stop, do not approach the whale and never attempt to
separate a mother from its calf. If you stop and remain still, you might be
very surprised when a curious juvenile approaches the boat to inspect you. If
you are so fortunate as to encounter a Humpback, you may also be privileged to
see an acrobatic display beyond description with leaps and rolls and breaches
and tail slapping.
Remember
how endangered all whales are and how tentative is their hold on survival. And
think about this: There are those in the Caribbean and elsewhere who would see
whaling return to our waters. If they have their way, instead of seeing a
mother whale gently lifting her new calf to the surface for its first breath, someday
soon you might see a ship hauling a carcass on board while hundreds of gallons
of blood flow into the water.
