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Humpback Whales

To look up into the mountains and see the steam rolling from a mountain stream
on a cold winters morning is a beautiful sight. However, to look out over the
horizon and see the white spray of salt water coming from the blow of a huge
humpback whale is much more exciting sight and a whole lot warmer. The first
time I had the opportunity to see the ocean was on a vacation to California,
when I was about 15 years old. It was even better than I had dreamed it would
be. The different animal in the ocean, the color of the water, and the warm sand
between my toes was what made me take a vacation to Hawaii. When I first saw the
humpback whale I was amazed at their huge size and how they could breach out of
the water so gracefully. It is as if they were trying to play or show off. So
when we were asked to choose a favorite animal, I had no problem deciding on the
humpback whale. The hump-back whale gets it’s name from the distinctive hump
in front of the dorsal fin and from the way it raises it’s back high above
water before diving. They are a member of the order Cetacea. This order is of
aquatic mammals and the humpback belongs to the suborder of the Mysticeti. The
Mysticeti are the baleen whales, which have three families and several species.

The family in which the humpback belongs is the Balaenopteridae, the true fin
backed whale. The thing that separates this genus from the other fin-backed
whales is the pectoral fins, which grow in lengths of about 16.4 feet. This
Genus is called Megaptera meaning great wing (Tinker 290). There was a
controversy over the species name in the late nineteenth and early twentieth
century. In 1932, Remington Kellogg finally settled the matter with Megatera
Novaeangliae (Cousteau 84). The common English name is the humpback whale. The
humpback whale lives in both the Atlantic and the Pacific oceans. Since we live
in the Pacific I’ll be discussing the humpbacks of the North Pacific. They
migrate from North to South. In the months of July through September they gather
in the Aleutian Islands, Bering Sea or the Chukchi Sea. They head south for the
winter. They go to one of three areas: Between the Bonin Islands, the Marianas
Islands, the Ryukyu Islands and Taiwan; The Hawaiian Islands, and along the
coast of Mexico (Tinker 291). One of the reasons these whales go north is for
feeding. They have a short food chain compared to most mammals. Phytoplankton
turns sunlight into energy and this energy is consumed by zooplankton. Small
fish eats the zooplankton and phytoplankton. The whale in turn eats the fish.

The chain is complete when waste products or dead whales decompose. They have a
very short time frame in which they eat compared to the twelve months out of the
year. They have not been seen feeding in Hawaii. It seems that they only feed
during the summer months up north. During the fasting periods, in Hawaii, they
survive on their blubber. They mix their diet with copepods, krill, and small
fish, primarily herring and capelin. They are considered filter feeders, using
baleen plates to filter out their food. They take huge amounts of water into
their mouth using a gulping method and then when they push the water out, they
put their tongue up so the water must pass through the baleens. The food becomes
trapped and falls toward the rear of the mouth. The two gulping methods humpback
whales use are lunge feeding and bubble net feeding. Lunge feeding is used when
food is abundant. The whale simply swims through the prey with its mouth open
engulfing the prey. They can do this vertically, laterally or inverted. This is
done toward the surface of the ocean. Bubble net feeding is used when the prey
is less abundant. The whale dives below the prey and discharges bubbles from its
blowhole. As the bubbles ascend they form a net that disorients the prey. Then
the whale swims upward and fills his mouth with the net of fish and bubbles
(Kaufman 55). Humpbacks have ventral grooves in their throat that expand
allowing an enormous amount of water to be gulped. Humpbacks consume nearly a
ton of food in a day’s time during their feeding season. The humpback
whale’s stomach consists of three chambers and the duodenal ampulla much like
a cow. The three