Animals of Antarctica
Emperor Penguins
Type: Bird
Diet: Carnivore
Average life span in the wild: 15 to 20 years
Size: 45 in (115 cm)
Weight: Up to 88 lbs (40 kg)
Group name: Colony
Relative: Size relative to a 6-ft (2-m) man
Emperors are the largest of all penguins-an average bird stands some 45 inches (115 centimeters) tall. These flightless animals live on the Antarctic ice and in the frigid surrounding waters.Penguins employ physiological adaptations and cooperative behaviors in order to deal with an incredibly harsh environment, where wind chills can reach -60 degree Celsius.They huddle together to escape wind and conserve
Diet: Carnivore
Average life span in the wild: 15 to 20 years
Size: 45 in (115 cm)
Weight: Up to 88 lbs (40 kg)
Group name: Colony
Relative: Size relative to a 6-ft (2-m) man
Emperors are the largest of all penguins-an average bird stands some 45 inches (115 centimeters) tall. These flightless animals live on the Antarctic ice and in the frigid surrounding waters.Penguins employ physiological adaptations and cooperative behaviors in order to deal with an incredibly harsh environment, where wind chills can reach -60 degree Celsius.They huddle together to escape wind and conserve
warmth. Individuals take turns moving to the group's protected and relatively
toasty interior. Once a penguin has warmed a bit it will move to the perimeter
of the group so that others can enjoy protection from the icy elements.
Emperor penguins spend the long winter on the open ice-and even
breed during this harsh season. Females lay a single egg and then promptly leave it behind.
They undertake an extended hunting trip that lasts some two months!
Depending on the extent of the ice pack, females may need to travel
some 50 miles (80 kilometers) just to reach the open ocean, where they will
feed on fish, squid, and krill. At sea, emperor penguins can dive to 1,850
feet (565 meters)-deeper than any other bird-and stay under for more than 20 minutes. Male emperors
keep the newly laid eggs warm, but they do not sit on them, as many other birds do. Males stand and
protect their eggs from the elements by balancing them on their feet and covering them with feathered
skin known as a brood pouch. During this two-month bout of babysitting
the males eat nothing and are at the mercy of the Antarctic elements. When female
penguins return to the breeding site, they bring a belly full of food that they regurgitate
for the newly hatched chicks. Meanwhile, their duty done, male emperors take to the sea in search of food for themselves.
Mothers care for their young chicks and protect them with the warmth of their own brood pouches.
Outside of this warm cocoon, a chick could die in just a few minutes. In December, Antarctic summer,
the pack ice begins to break up and open water appears near the breeding site, just as young emperor
penguins are ready to swim and fish on their own.
Blue Whales
The blue whale (Balaenoptera musculus)
is a marine mammal belonging to the baleen whales
(Mysticeti). At 30 metres (98 ft) in length and up to 173 tonnes (191 short tons)
in weight, it is the largest extant animal and is the heaviest known to have existed.Long and slender,
the blue whale's body can be various shades of bluish-grey dorsally and somewhat lighter underneath.
There are at least three distinct subspecies: B. m. musculus of the North Atlantic and North Pacific,
B. m. intermedia of the Southern Ocean and B. m. brevicauda (also known as the pygmy blue whale)
found in the Indian Ocean and South Pacific Ocean. B. m. indica, found in the Indian Ocean, may be
another subspecies. As with other baleen whales, its diet consists almost exclusively of small crustaceans known as krill.
Blue whales were abundant in nearly all the oceans on Earth until the beginning of the twentieth century.
For over a century, they were hunted almost to extinction by whalers until protected by the international community in 1966.
A 2002 report estimated there were 5,000 to 12,000 blue whales worldwide,in at least five groups. More recent research
into the pygmy subspecies suggests this may be an overestimate. Before whaling, the largest population was in the
Antarctic, numbering approximately 239,000 (range 202,000 to 311,000). There remain only much smaller (around 2,000)
concentrations in each of the eastern North Pacific, Antarctic, and Indian Ocean groups. There are two more groups in
the North Atlantic, and at least two in the Southern Hemisphere. As of 2014, the Californian blue whale population
has rebounded to nearly its pre-hunting population.
Size
By comparison, one of the largest known dinosaurs of the Mesozoic Era was Argentinosaurus,
which is estimated to have weighed up to 90 tonnes (99 short tons), comparable to the average
of blue whale. Blue whales are difficult to weigh because of their size. As a whole, blue
whales from the Northern Atlantic and Pacific appear to be smaller on average than those from
sub-Antarctic waters. Adult weights typically range from 73-136 tonnes (80-150 short tons).
There is some uncertainty about the biggest blue whale ever found, as most data came from
blue whales killed in Antarctic waters during the first half of the twentieth century, which
were collected by whalers not well-versed in standard zoological measurement techniques.
The heaviest weight ever reported was 173 metric tons (191 short tons) for a southern hemisphere female in 1947.
The longest whales ever recorded were two females measuring 33.6 and 33.3 metres (110 and 109 ft), although in
neither of these cases was the piecemeal weight gathered.
The longest whale measured by scientists was 29.9 metres (98 ft) long.
Lieut. The longest reported in the North Pacific was a 27.1 metres (89 ft)
female taken by Japanese whalers in 1959, and the longest reported
in the North Atlantic was a 28 metres (92 ft) female caught in the Davis Strait.
Humpback Whale
The humpback whale (Megaptera novaeangliae) is a species
of baleen whale. One of the larger rorqual species, adults range in length
from 12-16 m (39-52 ft) and weigh about 36,000 kg (79,000 lb). The humpback
has a distinctive body shape, with long pectoral fins and a knobbly head.
It is known for breaching and other distinctive surface behaviors, making
it popular with whale watchers. Males produce a complex song lasting 10 to
20 minutes, which they repeat for hours at a time. Its purpose is not clear,
though it may have a role in mating.Found in oceans and seas around the world,
humpback whales typically migrate up to 25,000 km (16,000 mi) each year. Humpbacks
feed only in summer, in polar waters, and migrate to tropical or subtropical waters
to breed and give birth in the winter when they fast and live off their fat reserves.
Their diet consists mostly of krill and small fish. Humpbacks have a diverse repertoire
of feeding methods, including the bubble net technique.Like other large whales, the humpback
was a target for the whaling industry. Once hunted to the brink of extinction, its population
fell by an estimated 90% before a 1966 moratorium. While stocks have partially recovered,
entanglement in fishing gear, collisions with ships, and noise pollution continue to impact
the population of 80,000.
Size
Fully grown males average 13-14 m (43-46 ft). Females are slightly larger at 15-16 m (49-52 ft);
one large recorded specimen was 19 m (62 ft) long and had pectoral fins measuring 6 m (20 ft) each. The largest
humpback on record, according to whaling records, was a female killed in the Caribbean; she was 27 m (89 ft) long with
a weight of 90 metric tons (99 short tons), although the reliability of this information is unconfirmed due to illogicality
of the record. Body mass typically is in the range of 25-30 metric tons (28-33 short tons), with large specimens weighing
over 40 metric tons (44 short tons).
Newborn calves are roughly the length of their mother's head. At birth, calves measure 6 m (20 ft) at 2 short tons (1.8 t).
They nurse for about six months, then mix nursing and independent feeding for possibly six months more. Humpback milk is 50% fat and pink in color.
Females reach sexual maturity at age five, achieving full adult size a little later. Males reach sexual maturity around seven years of age.