Tuesday, 20 September 2011

The humpback whale (Megaptera novaeangliae)

Humpback whale (Near Magawish Island - Hurghada - Red Sea - Egypt) Photo by/ Sandra Caramelle
i can recall spotting of those whales twice in my life , one time by Mr kiros paschalis behind shadwan island ..another time at the National geopgraphic history films of red sea at the times of Hans Hass and Cousteau ..but its there ..wish those whales stay away from intruders and fishermen .. Says Dr. Ehab M Tomoum one of Egypt’s leading diving pioneers. 
In HEPCA's blog Madda says "Commonly spotted all year round off Oman, sighting in the Gulf of Aden are limited and this fascinating creatures have been spotted in the Egyptian Red Sea only twice before (despite a very few not-confirmed sightings have been reported, two have been documented: a young individual off Dahab in 1992 and an adult in October 2006 off Sharm El Sheikh), making this recent sighting an incredible event indeed!"
Humpback whales live at the surface of the ocean, both in the open ocean and shallow coastline waters. When not migrating, they prefer shallow waters. They migrate from warm tropical waters where they breed and calve to arctic waters where they eat. Humpback whale distribution map. www.iucnredlist.org.
The humpback whale (Megaptera novaeangliae), One of the larger rorqual species, adults range in length from 12–16 metres (39–52 ft) and weigh approximately 36,000 kilograms (79,000 lb). The humpback has a distinctive body shape, with unusually long pectoral fins and a knobbly head. It is an acrobatic animal, often breaching and slapping the water. Males produce a complex song, which lasts for 10 to 20 minutes and is repeated for hours at a time. The purpose of the song is not yet clear, although it appears to have a role in mating.
Found in oceans and seas around the world, humpback whales typically migrate up to 25,000 kilometres (16,000 mi) each year. Humpbacks feed only in summer, in polar waters, and migrate to tropical or sub-tropical waters to breed and give birth in the winter. During the winter, humpbacks fast and live off their fat reserves. The species' diet consists mostly of krill and small fish. 

Humpbacks have a diverse repertoire of feeding methods, including the bubble net feeding technique.
Humpback whale - Photo by/ marine mammal laboratory and the dolphin institute
Humpback whales (Megaptera novaeangliae) are baleen whales (Suborder Mysticeti). They are one of 76 cetacean species, and are marine mammals.
Humpback showing his head - Photo by/ Sandra Caramelle
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.  Humpback whales have 14-35 throat grooves that run from the chin to the navel. These grooves allow their throat to expand during the huge intake of water during filter feeding. They have small, round bumps on the front of the head (called knobs or tubercles), edging the jaws.

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. 
Humpback whales grow to be about 52 feet (16 m) long, weighing 30-50 tons (27-45 tonnes). The females are slightly larger than males, as with all baleen whales. The four-chambered heart of the average humpback whale weighs about 430 pounds (195 kg) - about as much as three average adult human beings. 
underwater sighting of two Humpback whale (Hurghada - Red Sea - Egypt) Photo by/ Sandra Caramelle
Humpback whales breathe air at the surface of the water through 2 blowholes located near the top of the head. They spout (breathe) about 1-2 times per minute at rest, and 4-8 times per minutes after a deep dive. Their blow is a double stream of spray that rises 10-13 feet (3.1-4 m) above the surface of the water. 

The two blowholes located near the top of the head - Photo by/ Sandra Caramelle
 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. 

Photo by/ Sandra Caramelle
Photo by/ Sandra Caramelle

Photo by/ Sandra Caramelle
Photo by/ Sandra Caramelle
 Humpback whales are not the most critically endangered species of whale but they still need protection. Although large-scale commercial hunting of whales has reduced greatly since the end of the 20th century, some whaling, including of humpbacks, still occurs. Humpbacks and other whales also face other problems. Their ocean habitat is vulnerable and if pollution or other problems kill off a food supply, the whales go too. Individuals can do plenty to help save them.



Bibliography:    
  • Balcomb, K. and S. Minasian. 1984. The World's Whales. Smithsonian Books. W. W. Norton, New York.
  • Leatherwood, S.L. and R.R. Reeves. 1983. The Sierra Club Handbook of Whales and Dolphins. Sierra Club Books, San Francisco.
  • Winn, L.K. and H.E. Winn. 1985. Wings in the Sea; the Humpback Whale. University Press of New England, Hanover, NH.
  • http://redseadolphinproject.wordpress.com/2011/09/17/humpback-whales-yes-in-my-backyard/
  • http://en.wikipedia.org/wiki/Humpback_whale

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