Sperm Whale

Photograph by Brian J. Skerry

Sperm whales' heads are filled with a mysterious substance called spermaceti. Scientists have yet to understand its function, but believe it may help the animal regulate its buoyancy.

Sperm whales are easily recognized by their massive heads and prominent rounded foreheads. They have the largest brain of any creature known to have lived on Earth. Their heads also hold large quantities of a substance called spermaceti. Whalers once believed that the oily fluid was sperm, but scientists still do not understand the function of spermaceti. One common theory is that the fluid—which hardens to wax when cold—helps the whale alter its buoyancy so it can dive deep and rise again. Sperm whales are known to dive as deep as 3,280 feet (1,000 meters) in search of squid to eat. These giant mammals must hold their breath for up to 90 minutes on such dives.

These toothed whales eat thousands of pounds of fish and squid—about one ton (907 kg) per day.

Sperm whales are often spotted in groups (called pods) of some 15 to 20 animals. Pods include females and their young, while males may roam solo or move from group to group. Females and calves remain in tropical or subtropical waters all year long, and apparently practice communal childcare. Males migrate to higher latitudes, alone or in groups, and head back towards the equator to breed. Driven by their tale fluke, approximately 16 feet (5 meters) from tip to tip, they can cruise the oceans at around 23 miles (37 kilometers) per hour.

These popular leviathans are vocal and emit a series of "clangs" that may be used for communication or for echolocation. Animals that use echolocation emit sounds that travel underwater until they encounter objects, then bounce back to their senders—revealing the location, size, and shape of their target.

Sperm whales were mainstays of whaling's 18th and 19th century heyday. A mythical albino sperm whale was immortalized in Herman Melville's Moby Dick, though Ahab's nemesis was apparently based on a real animal whalers called Mocha Dick. The animals were targeted for oil and ambergris, a substance that forms around squid beaks in a whale's stomach. Ambergris was (and remains) a very valuable substance once used in perfumes.

Despite large population drops due to whaling, sperm whales are still fairly numerous.

Type: Mammal

Diet: Carnivore

Size: 49 to 59 ft (15 to 18 m)

Weight: 35 to 45 tons (31.8 to 40.8 metric tons)

Group name: Pod

Did you know? Sperm whales and giant squid may be mortal enemies. Many stories of deadly battles between these two massive animals exist, and sperm whales have even been seen with suction cup-shaped wounds and remnants of giant squid in their stomachs.

Protection status: Endangered

source : http://animals.nationalgeographic.com, Youtube

Bowhead Whale

The bowhead is one of the largest of the baleen whale species. Adults average nearly 19 m long (65 ft.) and may weigh more than 60 t (66 tn.).

Its high-arching mouth ("bowhead") is distinctive, and the ponderous head forms more than one-third of its body length. Large sheets of baleen suspended from the upper jaw are used as screens for catching its food, mainly shrimp-like crustaceans known as "krill".

Some Arctic adaptations include:

• thick blubber that provides the animal with food reserves and insulation against cold seas
• an absence of a dorsal fin, which is useful for moving among ice floes
• a massive head that can break through ice up to 0.6 m (2 ft.) thick when it is necessary to create breathing holes.

This slow-moving whale inhabits the Arctic Ocean and the sub-Arctic waters of the north Atlantic and Pacific Oceans. They cruise along at 2 to 4 knots, and sound for up to 30 minutes.

These whales are among the longest-lived mammals; they are still growing after age 50, and have been proven to live well beyond 100 years.

Whaling for the bowhead began near Spitsbergen as early as 1611 and continued until the early 1900s. Around that time the demand for whalebone dwindled, and the number of animals became too low for hunting them to be of economic interest.

The bowhead has been protected by the International Whaling Commission since 1937. However, native peoples are still allowed to hunt them for food. Aside from humans, the bowhead's only other predator is the killer whale.

Bowhead populations seem to be recovering well in the Bering, Chukchi and Beaufort Seas, but recovery has been slower in the Baffin Island, Greenland and Spitsbergen regions, where whaling was more intensive and carried on over a longer period. The species remains endangered, with approximately 8000 bowheads in existence today.

source : http://www.sdnhm.org, http://nature.ca, Youtube

Bottlenose Dolphin

Bottlenose Dolphin Profile

Bottlenose dolphins are well known as the intelligent and charismatic stars of many aquarium shows. Their curved mouths give the appearance of a friendly, permanent smile, and they can be trained to perform complex tricks.

In the wild, these sleek swimmers can reach speeds of over 18 miles (30 kilometers) an hour. They surface often to breathe, doing so two or three times a minute. Bottlenose dolphins travel in social groups and communicate with each other by a complex system of squeaks and whistles. Schools have been known to come to the aid of an injured dolphin and help it to the surface.

Bottlenose dolphins track their prey through the expert use of echolocation. They can make up to 1,000 clicking noises per second. These sounds travel underwater until they encounter objects, then bounce back to their dolphin senders, revealing the location, size, and shape of their target.

When dolphins are feeding, that target is often a bottom-dwelling fish, though they also eat shrimp and squid. These clever animals are also sometimes spotted following fishing boats in hopes of dining on leftovers.

Bottlenose dolphins are found in tropical oceans and other warm waters around the globe. They were once widely hunted for meat and oil (used for lamps and cooking), but today only limited dolphin fishing occurs. However, dolphins are threatened by commercial fishing for other species, like tuna, and can become mortally entangled in nets and other fishing equipment.

All dolphins, including the bottlenose, are porpoises. Although some people use these names interchangeably, porpoises are actually a larger group that also includes animals like the orca and the beluga whale.

Average lifespan in the wild: 45 to 50 years

Size: 10 to 14 ft (3 to 4.2 m)

Weight: 1,100 lbs (500 kg)

Group name: Pod

Did you know? Bottlenose dolphins have been observed to breach up to 16 feet (4.9 meters) out of the water, landing with a splash on their back or side.

Fast Facts
Type: Mammal
Diet: Carnivore
Average lifespan in the wild: 45 to 50 years
Size: 10 to 14 ft (3 to 4.2 m)
Weight: 1,100 lbs (500 kg)
Group name: Pod
Did you know? Bottlenose dolphins have been observed to breach up to 16 feet (4.9 meters) out of the water, landing with a splash on their back or side.


source : http://animals.nationalgeographic.com, Youtube, seapics.com

Beluga Whale

Beluga Whale Profile

Belugas are also called white whales, and their unusual color makes them one of the most familiar and easily distinguishable of all the whales. Calves are born gray or even brown and only fade to white as they become sexually mature around five years of age.

White whales are smallish, ranging from 13 to 20 feet (4 to 6.1 meters) in length. They have rounded foreheads and no dorsal fin.

Belugas generally live together in small groups known as pods. They are social animals and very vocal communicators that employ a diversified language of clicks, whistles, and clangs. Belugas can also mimic a variety of other sounds.

These whales are common in the Arctic Ocean's coastal waters, though they are found in subarctic waters as well. Arctic belugas migrate southward in large herds when the sea freezes over. Animals trapped by Arctic ice often die, and they are prey for polar bears, killer whales, and for Arctic people. They are hunted by indigenous people of the north, and by commercial fisheries that brought some populations, such as those in the Gulf of St. Lawrence, to near collapse.

Fast Facts

Type: Mammal

Diet: Carnivore

Average lifespan in the wild: 35 to 50 years

Size: 13 to 20 ft (4 to 6.1 m)

Weight: 2,000 to 3,000 pounds (907 to 1,361 kilograms)

Group name: Pod

Did you know? Unlike most other whales, the beluga has a flexible neck that enables it to turn its head in all directions.

Protection status: Threatened

source : http://animals.nationalgeographic.com, Youtube, www.oneinchpunch.net