Subject: humpback whale information

Lindsay J Porter (h9390327@hkucc.hku.hk)
Fri, 5 Dec 1997 11:18:22 +0800

Hello my name is Katie, I am doing a research project on the humpback
>whale. If you could send me any infromation on this topic it would be
>most helpful. 

Dear Katie,
Try looking on the website 
http://www.oit.itd.umich.edu/bio/doc.cgi/Chordata/Mammalia/Cetacea/Balaenopt
eridae/Megaptera_novaeangliae.ftl

I have edited some text from this site I hope you find useful.  Other
humpback sites include...
Humpback Whale Adoption
http://www.webcom.com/~iwcwww/whale_adoption/waphome.html
3D animation of feeding humpbacks
http://fas.sfu.ca/cs/research/projects/Whales
Hawaiian Humpbacks
http://www.nos.noaa.gov/nmsp/hinms
Hervey Bay, Australian humpbacks
http://owl.qut.edu.au/

I hope you find this a useful start to your research
best wishes

Lindsay

>Humpback whales belong to the family 
>Balaenopteridae (rorquals)
>This family includes 6 species, including minke, Bryde's, sei, fin,
humpback, and >blue whales. These range in size from the relatively small
minke whale, about 8-10 >m in length, to the giant blue whale, at 20 - 28 m
length and
>almost 200,000 kg weight. The shape and color of the body, and the size and
>shape of fins, varies considerably among
>species. A shared external trait is the presence of deep longitudinal
grooves in the skin, running over the entire throat and
>chest. 

>The baleen plates of rorquals are short and broad. These species feed by
gulping >large quantities of water and straining
>crustaceans and fish by shooting the water out between the baleen plates.
>
>Rorquals feed in cold currents at high latitudes during the summer, mostly
on the >eastern sides of the oceans. Some species
>range mostly offshore, others are more often found in coastal waters. Their
food is >primarily krill, euphausiid crustaceans,
>which congregate near the surface in cold water. Blue whales eat little but
>euphausiids; other species have a broader diet,
>even including some fish. During the autumn, most species migrate toward
>equatorial latitudes. They fast for several month, living
>by metabolizing blubber.
>

>The geographical range of the humpback whale is that of polar and tropical
>waters, particularly those of the Atlantic, Artic, and Pacific Oceans. It
also >includes the waters of the Berring Sea and the
>water surrounding Antartica. 
>

HUMPBACK WHALES 
Physical Characteristics

>Humpback females are larger than the males. They are one of the few species
of >mammals for which this is true. 
>
>The most distictive external features of humpbacks are the number of
ventral >pleats, fliper size and form, and fluke coloration
>and shape. The humpback has the greatest relative blubber thickness for its
size of >any rorqual, and is usually second only to
>the blue whale in absolute thickness. Blubber thickness varies at different
times of >the year, and with age and physiological
>condition. 
>

>Food Habits
>Humpbacks are generalized feeders. They are highly mobile and opportunistic.
>They feed on plankton, the plant and animal life at the surface of the
ocean's > water, or fish in large patches or schools. They do eat commercially
> exploited fishes. Feeding by humpbacks takes place during the summer. 

> Feeding habits: Typically an animal takes the food and water into its
mouth, >while the ventral grooves in the throat
> allow for expansion. Once all of the food is present in the mouth, the
mouth is >then closed and the water is pressed out.
> Meanwhile, the food is caught in the baleen plates and is then swallowed.
This > process is aided by the internal
> mechanism of rorqual feeding: the tongue. 

>     Humpbacks have five main feeding behaviors (the fist three are more
commonly observed than the last two):
>
>     1. Humpbacks have an elaborate feeding behavior in which they lie on
the >         ocean's surface and swim in a circle. While
>        doing so, they strike the water with their flukes forming a "ring
of foam," >        surrounding their prey. Then, they dive under
>        the ring and resurface in the center with their mouth open to
obtain their >        prey.
>
>     2. Humpbacks also practice a behavior referred to as lunging. They
feed by >         swimming vertically or obliquely up
>         through aggregations of plankton or fish. This occurs only when
their food is >         abundant. In addition some variation may
>         occur by means of lateral and/or inverted lunging.
>
>     3. Some humpbacks practice a feeding behavior entitled: bubble
behavior. It >         refers to underwater exhalations: bubble
>         clouds and bubble columns. 
>
>       cloud: This large inter-connected mass of bubbles, is formed by one
>       underwater exhalation which concentrates or
>       herds a mass of prey. Feeding is presumed to occur underwater. After
that the >       humpback rises slowly to the surface
>       within the bubble cloud.
>
>      After several blows and some shallow diving, the manuever is
repeated. This >      appears to assist in prey detection or in
>      the possible capturing methods, immobilizing and confusing prey. It
does this >      by causing a dumping response among
>      the prey, aiding the predator in prey detection, or diguising the
predator from >      the prey. 
>
>      column: This is formed as a humpback swims underwater in a broad
circle >      while exhaling. However, an individual
>      column forms rows, semicircles, or complete circles. In addition it
acts like a >      seive net, carying out its purpose of
>      concentrating or herding the prey.
>
>     4. When humpbacks use the tail slashing method, the individual animal
swims >         in a large circle while slashing its tail
>         through the water. The actual feeding takes place in the center of
the >         turbulence.
>
>     5. Humpbacks that use the "inside loop behavior" make a shallow dive,
while    >         hitting the water with their flukes as they
>         submerge. A 180 degree roll is then rapily executed as the
animalmakes a >         sharp U turn(the "inside loop") and then the
>        whale lunge feeds slowly through the turbulent area created by its
flukes. The >         whale feeds beside the area of
>         turbulence. 


>Reproduction
>Humpbacks appear to possess a polygynous/polygamous mating system, with
>the male competing aggressively for
>access to oestrous females. There is no parental investment on the part of
the >males.
>
>The reproductive habits of humpback whales are typically mammalian. The
>breeding seasonis during the winter, and
>breeding takes place in tropical waters. 
>

> Postnatal Development: The calves are born in the warm tropical water and
>subtropical waters of each hemisphere.
>The newborns are usually 4-5 m long, and they are suckled by their mothers
for >about 5 months. The females' milk is
>highly nutritive, containing high amounts of fat, protein, lactose and
water. Sexual >maturity is usually reached between
> 4-5 years. 
> Breeding usually takes place once every two years, but it may occur twice
every >three years. In the latter situation,
> lactation may last longer that 5 months.
>

>Behavior
>Humpback whales live in groups. They migrate seasonally from the tropics to
the >northern feeding grounds. In the
>tropics, they are found in dense aggregations on shallow banks. They are
usually >deep oceanic migrators between their
>feeding and breeding grounds; the vast majority of humpbacks do not come
into >coastal waters until they reach the
>latitudes of Long Island, New York or, Cape Cod, Massachussetts. They tend
to >disperse more widely in deep waters
>then when in shallow water.
>
>Migration: 
>Humpbacks migrate between northern and southern latitudes in phase with the
climactic cycle. Migration  is largely connected with the two functions of
feeding >and reproduction. 

>Humpbacks appear in large numbers is subartic waters in the spring and
remain >there until the summer. As the season
> advances, they become less numerous. The reason for humpback migration is
>thought to be that they seek warmer
>water in which to bring forth their young and that pairing and mating takes
place at >about the same time. 

> Swimming and diving: 
>Swimming speed may reach 27 km per hour and during migration, it may reach
>3.8-14.3 km
> per hour.Whales with calves swim the slowest, while lone whales travel
faster >than those in groups.
>
> Humpbacks dive 6-7 m for 15-20 minutes. During diving blows are not
regular >and flukes are not lifted as the whale
> submerges. In longer dives the flukes are lifted and the animal surfaces
between >dives for about 4 minutes, while
> blowing regularly. 
>
>Habitat
>The habitat of the humpback whale consists of polar to tropical waters,
including >the waters of the Artic, Atlantic, and
> Pacific Oceans, as well as, the waters surrounding Antartica and the
Bering Strait. >During migration, they are found in
>coastal and deep oceanic waters. Generally, they do not come into coastal
waters >until they reach the lattitudes of
> Long Island, New York and Cape Cod, Massachessetts. This occurs among
>humpbacks all over the world. 
>
>Humpbacks are divided into several populations. These are for the most part
>isolated, but with a little interchange in
> some cases. There are two stocks in the north Atlantic Ocean and two in
the >north Pacific. There are also seven isolated stocks in the southern
hemisphere.
>
>Currently, there are an estimated 6,000 humpbacks in the earth's waters,
with >possibly 1000- 3000 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. At the present time
there >is no special status provided to the
>humpback whales, because the global humpback population has begun to
>strengthen and replenish itself. They received some
>protection in 1985 when the International Whaling Commission instituted a
>moratorium on commercial whaling. In the early
>part of the twentieth century, during the modern whaling era, the 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 60,000 humpbacks were killed between 1910- 1916 in the southern
>hemisphere, and there were other peaks of
>exploitation in the 1930's and 1950's. In the North Pacific, there were
peak catches >of over 3000 in the years 1962-3.
>
>In order to combat the problem of depletion, catching humpback whales was
>prohibited in the Antartic in 1939, although that
>plan was abandoned in 1949. In the southern hemisphere hunting was banned
in >1963, in the North Atlantic in 1956, and
>finally in the North Pacific in 1966. 
>
>^ Other Comments
>
>The common name "humpback" 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 man. They are sometimes harrassed, not killed, by
killer >whales, and sharks feed on their dead
>bodies. 
>

>Pollutants that have been reported from the blubber of humpbacks include
DDT, >PCB's, chlordane, and dieldrin. The levels
>of these toxins vary during the migratory pattern of the humpbacks. The
levels are >highest during feeding and are lowest
>during breeding. 

email h9390327@hkucc.hku.hk
Dolphin Research Group
The Swire Institute of Marine Science
The University of Hong Kong
Cape d'Aguilar
Hong Kong
website: http://www.webdivers.co.uk/dolphin/index.html