Whales and Dolphins of Australia and New Zealand: an identification guide. Bryden, M. Dugongs, Whales, Dolphins and Seals. A guide to the sea mammals of Australasia. Menkhorst, P. A Field Guide to Mammals of Australia. Oxford University Press, Melbourne, Australia. Reeves, R. Back to top. Search website Submit Search. Close Modal Dialog. Humpbacks often feed in large groups and are famous for their "song.
The whales may repeat the same song for several hours. Researchers are not certain why humpback whales sing. They have hypothesised that the songs attract females or are used as territorial markers. Winters are spent mating and calving in warm sub-tropical waters, with an annual migration back to colder waters to feed.
This population migrates south to the Caribbean and south from the southern Bahamas to Grenada, the Grenadines and Venezuela. Diet Humpbacks are baleen whales, which means they filter their food through baleen plates.
They strain krill, anchovies, cod, sardines, mackerel, capelin, and other schooling fish from the waters. Some humpbacks have been observed creating "bubble nets" to catch their prey. The whales dive deep then swim up in a spiral pattern, while releasing a steady stream of bubbles from their blow holes.
As the bubbles rise they form a "net" that surrounds the whales' prey. The whales swim up through the centre of the bubble net and feed on the prey trapped inside. Breeding Humpback whales have complicated courtship behaviours. Meal made from whale bones was used as fertilizer. However, these animals are no longer hunted extensively. They do continue to have some economic impact, as ecotourism and whale sighting tours are quite popular in appropriate coastal areas. Humpback whales staying close to the shore on the Eastern Canadian seaboard damage cod and herring traps and can tear loose long lengths of a set net.
Currently, there are an estimated 6, humpbacks in the earth's waters, with possibly 1, to 3, more. The healthiest populations occur in the western north Atlantic Ocean. A few other areas in which there are small populations include the waters near Beguia, Cape Verde, Greenland, and Tonga. Global humpback populations have begun to strengthen, although this species is still a conservation concern. Humpback whales received some protection in when the International Whaling Commission instituted a moratorium on commercial whaling.
In the early part of the twentieth century, during the modern whaling era, humpback whales were highly vulnerable due to their tendency to aggregate on the tropical breeding grounds and to come close to the shore on the northern feeding grounds. More than 60, humpbacks were killed between to in the southern hemisphere, and there were other peaks of exploitation in the 's and 's.
In the North Pacific, there were peak catches of over 3, in to In order to combat the problem of depletion, catching humpback whales was prohibited in the Antartic in , although that plan was abandoned in In the southern hemisphere, hunting was banned in In the North Atlantic, hunting was banned in Finally hunting was banned in the North Pacific in The common name "humpback" also comes from the animal's tendency to round its back when diving. Some humpbacks have whitish, oval-shaped scars, which are the marks of parasitic sea lampreys.
Humpback whales have few predators other than humans. They are sometimes harassed, perhaps killed, by killer whales, and sharks feed on their dead bodies.
Little is known about the diseases that affect humpback whales. However, true rorquals get cirrhosis of the liver and mastitis.
It is unlear as to whether humpbacks also get them. Humpbacks are the most parasitized of all of the Balaenopteridae. They tend to carry a wide variety of ecto and endoparasites. The number of parasites may be related to the swimming speed of this species. The slow pace of humpbacks is thought to allow accumulation of parasites to occur.
Humpbacks have different types of whale lice living in their scars, scratches, chins, throats, and urogenital slits. Barnacles also live in their throats, chins, and urogenital slits. Some endoparasites that live within the whales are trematodes, cestodes, nematodes, acanthocephalans. Helminths live in the blubber, liver, mesentery, and intestine, while Ogmogaster ceti a commensal nematode specific to the Balaenopteridae lives in the baleen plates.
The levels of these toxins vary during the migratory pattern of the humpbacks. The levels are highest during feeding and are lowest during breeding. It is the second largest ocean in the world after the Pacific Ocean. Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones.
Bottom habitats in the very deepest oceans below m are sometimes referred to as the abyssal zone. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends.
Synapomorphy of the Bilateria. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a now extinct synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds. Used mainly by aquatic invertebrates, especially plankton, but also by baleen whales. Iteroparous animals must, by definition, survive over multiple seasons or periodic condition changes.
Compare to phytoplankton. Encyclopedia Britannica, vol 5. William Benton, Publisher, Chicago. Encyclopedia Britannica, vol The New Encyclopedia Britannica, vol Univeristy of Chicago Press, Chicago. David Macdonald, ed.
Humpback whale. The Encyclopedia of Mammals. Facts on File Press, New York. Ridgway, S. Ridway and Sir Richard Harrison, eds. Handbook of Marine Mammals. Academic Press Harcourt Brace, London. Humpback whales are known for their magical songs, which travel for great distances through the world's oceans. These sequences of moans, howls, cries, and other noises are quite complex and often continue for hours on end.
Scientists are studying these sounds to decipher their meaning. It is most likely that humpbacks sing to communicate with others and to attract potential mates. Humpback calves are known to "whisper" to their mothers. Listen to a humpback whale song and explore what it looks like as sheet music. These baleen whales are found near coastlines, feeding on tiny shrimp-like krill, plankton, and small fish.
Humpbacks migrate annually from summer feeding grounds near the poles to warmer winter breeding waters closer to the Equator. Mothers and their young swim close together, often touching one another with their flippers with what appear to be gestures of affection. Females nurse their calves for almost a year, though it takes far longer than that for a humpback whale to reach full adulthood.
Calves do not stop growing until they are 10 years old. Humpbacks are powerful swimmers, and they use their massive tail fins, called flukes, to propel themselves through the water and sometimes completely out of it. These whales, like others, regularly leap from the water, landing with a tremendous splash. Scientists aren't sure if this breaching behavior serves some purpose, such as cleaning pests from the whale's skin, or whether whales simply do it for fun. How scientists are unlocking the hidden world of whale culture.
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