What is a Humpback Whale?
The humpback whale, Megaptera novaeangliae is a large baleen whale noted for its mysterious song. Humpbacks are found in most of Earth’s oceans and seas, and are occasionally objects of legends or worship. There are believed to be about 75,000 humpback whales alive, but populations have never fully recovered from large-scale whaling industries of the 17th-20th centuries.
Humpbacks are distinguishable by their characteristic long dorsal fin that forms the hump on their back for which they are named. They are mostly black, but may have white patterns on their underside, fins and tail fluke. The distinctive patterns of color and ridges on their flukes are used for identification photographs, as no two humpback tails are exactly alike.
At birth, a humpback whale weighs approximately one ton (907 kg,) and is between 10 and 15 feet (3-4.5 m) in length. A mature whale will be between 40-50 feet (12.2-15.2 m) long and weight 25-40 tons (22,680-36,287 kg.) Females reproduce every two or three years, upon reaching sexual maturity between the ages of five and seven. For many years, experts believed the average Humpback lived 50-60 years, but recent specimens of similar whale species have been found to be much older. It is now believed possible that humpbacks could live for over a hundred years.
The humpback whale is classified as a baleen whale, and thus does not have teeth. Instead, they have a series of flexible plates made out of keratin in their mouths, through which they can filter their food. Their diet consists of small fish, shrimp and krill. Humpbacks use a hunting technique called bubble net fishing, where a group of whales swim in a circle, blowing bubbles through their blowholes to surround fish in a ring. After they have sufficiently enclosed their prey, the whales will take turns darting through the circle to swallow the fish.
By forcing air through their blowholes, the male humpback whale can produce a vocal pattern or song. Each song lasts for between 10-20 minutes, and is sung by all males in a regional group. Although all males sing the same song, the song pattern can change over seasons. Despite extensive studies, experts remain baffled by the songs. Although theories suggest various functions of the songs, such as breeding or dominance behavior, no theory has been conclusively proven.
The humpback whale was hunted extensively during the days of widespread commercial whaling, and the global population is believed to have fallen to as low as 10% of its pre-whaling levels. Despite an International Whaling Commission (IWC) ban in the 1960s, some nations continued to hunt humpbacks for commercial and research purposes. In 2007, Japan announced its intention to kill 50 humpbacks for research purposes, and was met with global protests. The hunt was postponed pending an IWC conference regarding the matter.
Despite the IWC ban, the humpback whale remains in danger from noise and water pollution, collisions with ships, and entanglements in commercial fishing gear. Although population levels have recovered somewhat since the 1960s ban, the species has not yet regained pre-whaling populations, and is considered by some experts to be vulnerable to extinction in the future. The popularity of whale-watching industries is hopeful for the species, but experts warn that conservation measures for the humpback whale must be taken seriously if humans intend to protect the animals from harm.
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