Humpback Whales, gentle giants of the sea, travel thousands of miles (kilometers) each year between the Arctic or the Antarctic and the tropics. During the winter months Humpback Whales migrate to the tropics where it is nice and warm to give birth to their young. This usually lasts from December to April. When springtime comes they travel back to the Arctic for feeding. Whales that live in the Antarctic do the opposite. Since the seasons in the Southern Hemisphere are opposite of the North, during December to April they feed in the Antarctic because it is quite warm. When winter comes, around the months of May to September, they travel north to the tropics. When Humpbacks migrate they travel in groups that are spread out to a long distance. Since whales have to take in a lot of food, by scattering themselves they are more likely to find a feeding place.
They are large gentle creatures. Humpback Whales are known as Cetaceans. Cetaceans are marine mammals. They breathe, give birth to live babies, and nurse the young with milk. On an average, Humpback Whales are 75 - 90 feet (22.86 - 27.43m) in length. They weigh between 25 -40 tons (22,680 - 40,824kg). The estimated life span is 95 years. The whales have smooth and shiny skin that feels sort of rubbery. During their feeding season Humpbacks build up their blubber. This fatty layer lies underneath the skin. The blubber layer can be as thick as 6 inches (15cm). The blubber keeps the whales' body warm even in freezing cold water. On the head of the whales are many bumps called tubercles. On each tubercle sticks out a stiff hair called vibrissa. Each tubercle is connected to a complex network of nerves. Scientists believe they are for sensory functions. One way to tell one Humpback from the other is by the pattern of the tail called flukes. Like the human fingerprints, each whale has a unique pattern of its own. Humpbacks don't have teeth, but they have hair-like filtration arrangements. These hair-like teeth are called baleen. Thus, Humpbacks fit into the category of Baleen Whales.
As winter nears, hormonal change begins to occur in both the males and the females. Males start to produce more testosterone and sperm. The females are getting ready to ovulate, and be impregnated. Whales are famous for their songs. At this time the males begin to sing to attract their mate. During this time, there are occasional fights between males competing for one female. When a male finds a female they would mate. They swim together belly facing belly. If the female is impregnated, it'll take her 11 - 12 months before giving birth to a calf. The mating cycle only allows them to produce one calf every other year. Twin births are very uncommon. Scientists believe the tail comes out first then the head. A newborn, on an average, measures 16 feet (5m) in length. Females nurse their young with milk. Whale milk contains 40% fat, whereas cow milk only 4%. The mother produces 1,000 pounds (450kg) of milk each day. In a week the calves are double their size. The mother nurses the calf for 6 months. At this stage they can eat solid food. When they are adult size, the calves start to practice diving, breaching, and holding their breath. The mother is always there to protect her young.
Humpbacks feed on schooling fish, plankton, and krill. They would scoop into their mouth hundreds of gallons of water. They push the water back out with their tongue. The baleen inside the mouth filters the food. When the Humpbacks are catching their food, they would swim around their prey and blowing bubbles. This way their prey cannot escape and also they can't see where they are going.
These giants of the sea, are going toward extinction. People have been killing them for the meat, blubber, and baleen. The blubber they can sell it for lamps, and the baleen they can make a profit out of numerous products. Ninety-five percent of the whales were killed by human exploitation. As technology advances people are developing more efficient weapons to hunt down these whales. Now they have the ability to remain at sea for many days, and the crafts are much sturdier than many centuries ago. Some countries see the important need to preserve the whales. In 1964 they formed the International Whaling Commission (IWC). This organization limited months when hunter can go whaling. Some countries, like the U.S., have stopped whaling. In 1973, the United Nation pressed on to end whaling, but it failed. Again, in 1988, the IWC voted to end whaling, but it was also a failure. Thus, non-whaling countries took the responsibility on their hand to encourage other whaling countries to end whale hunt.
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