Whales

Frequently Asked Questions

What are whales?

Whales are mammals.

They are warm blooded, breath air through lungs and give birth to live young that are suckled on milk secreted from the mother’s mammary glands. Many of the features we associate with other mammals have been modified or lost during the long process of evolution from land dwelling ancestors and they have become superbly adapted to life in oceans, seas and rivers.

How many types of whales are there?

Whales, dolphins and porpoises, collectively known as cetaceans and are divided into two groups, the toothed whales or odontocetes and the baleen whales or mysticetes.

The toothed whales generally feed on larger food items such as fish or squid and include groups such as the river dolphins, dolphins, porpoises, beluga, narwhal, Killer Whales, Sperm Whale, pygmy sperm whales and beaked whales.

There are around 72 species worldwide at present.

The baleen whales feed by filtering seawater to trap food such as planktonic invertebrates (e.g. krill), copepods, amphipods and small fish. They differ from the toothed whales in generally being larger, having baleen instead of teeth and having paired nostrils. The mysteceti include species such as the Gray Whale, Right Whales, Pygmy Right Whale and the rorqual’ a group that includes the Blue, Fin, minkes, Sei, Bryde’s and Humpback Whales.

There are around 13 species worldwide at present.

How many whales are there in Australia?

At present there are around 44 species recorded from Australia, 35 of these are toothed whales and 9 are baleen whales.

Of the toothed whales, 19 species are from the family Delphinidae (including dolphins, pilot whales and Killer Whales) and 12 are from the family Ziphiidae (beaked whales). Also included are the Pygmy Sperm Whale, Dwarf Sperm Whale, Sperm Whale and Spectacled Porpoise.

The baleen whales include the Southern Right Whale, Pygmy Right Whale and seven species of rorquals (a group characterized by the presence of long folds of skin behind and below the mouth).

The number of whales species recognized worldwide and in Australia is constantly changing as the results of ongoing morphological and molecular studies become available.

What are whales closest relatives?

Because whales are so different from any land mammal it has been very difficult to determine their precise origins. Recent fossil discoveries and molecular studies indicate that hippopotamuses are the nearest living relatives of whales.

What do whales eat?

The large baleen whales (mysticetes) obtain their food by filter feeding using comb-like baleen plates that grow from the roof of the mouth. Prey is captured either by gulping large amounts of seawater and forcing it across the plates thereby trapping small food items, or by ‘skimming’ across the surface of the water and then removing trapped food with the tongue. Items such as krill, (shrimp-like crustaceans), copepods, amphipods, molluscs, polychaete worms, other planktonic invertebrates and schooling fish make up most of the diet of the baleen whales.

The toothed whales (odontocetes) hunt and eat a wider range of larger food items including fish, squid, octopus, molluscs and polychaete worms. Some species, such as the Killer Whale eat other cetaceans, seals and sea otters.

Why do baleen whales have two nostrils and toothed whales have one?

Is there a reason for the difference?

Scientists believe there may be an evolutionary reason for this difference, perhaps in symmetry in the skull and the development of echolocation. Toothed whales echolocate, using their air passages to generate sounds (air is moved between sacs under the blowhole to generate high-pitched sounds) . We do not think that baleen whales use echolocation or, if so, to a much more limited extent. However, baleen whales do generate very low-frequency sounds that may allow for extremely long-distance communication.

How do whales breathe?

Whales are voluntary breathers meaning they have to consciously breath in and out (it’s not an involuntary reaction like we have). They swim to the surface to draw in air through their blowholes. Whales have limited breathing functions through their mouths. When a whale inhales, it fills up its lungs to capacity each time and then exhales 90% of its air supply with each breath. Humans exhale only 25% of their lung capacity. The whales exhale through the blowholes, a whole exhale in less than half a second and sometimes at over 300 mps, while inhaling takes place in a leisurely second.

Whales are often seen breaching, and flipper and tail slapping. For what purpose are these actions?

These activities performed by surface active groups are usually involved in breeding behaviors. Researchers think the males are competing for the chance to mate with available females. Some of the behaviors shown were breaching, flipper/pec (pectoral fin) slapping and tail slapping. Breaches and slaps, in addition to being aggressive displays during courtship, may also be a play behavior in juvenile and adult whales Breaches and slaps may also be used to remove pesky barnacles or old skin (a form of grooming).

What size can whales grow to?

MINKE WHALE.

BRYDE'S WHALE.

HUMPBACK WHALE.

SEI WHALE.

SPERM WHALE.

FIN WHALE.

BLUE WHALE. *

* On display at the Eden Killer Whale Museum are the lower jaw bones from the largest Blue Whale ever caught by a hand-held harpoon from an open whale boat.

            It was harpooned by Archer Davidson in a “5 oared” open whale boat at Twofold Bay in 1910

            The Whale Boat measured:-        6.8 metres (22 foot) in length.

            The Blue Whale measured:-        29.8 metres (97 foot) in length.    200+ tonnes in weight. (Estimated)   Jaw Bones are 8.3 metres (27 foot) long.

Killer Whales (Orcinus Orcas)

Frequently Asked Questions

What are Killer Whales?
Killer Whales or Orcinus Orcas are marine mammals. They are one of 85 Whale (cetacean) species. The killer whale is a toothed whale (Odontoceti) and is an efficient predator, even attacking huge blue whales. Killers live in small, close-knit, life-long pods and have one blowhole. Killers breathe air at the surface of the water through this blowhole which is located near the top of its head. Their blow is a single, low bushy cloud. The killer whale belongs to the family of dolphins and is its largest member. It is sometimes called the "wolf of the sea" because its behavior is similar. This species was named in 1758.

How do they live?
Killer whales live in small pods of 6-40 whales; they are very social animals. The bonds between the close-knit members of killer whale pods are strong and last for life. The members of a pod hunt together in a very sophisticated manner, attacking even very large prey and then sharing it. The pod members protect the young, the sick and the injured.

How big is a Killer Whale?
Killer whales grow to be about 8-10 m  long, weighing more than 3.500-5.500 kg. The male killer is larger than the female.

What do Killer Whales look like?
The killer whale's skin is mostly black with distinctive white patches. Killers have stocky bodies and a rounded head with a distinctive beak. They have a tall, falcate (sickle-shaped) dorsal fin and large, paddle-like flippers. The dorsal fin of the male is taller (up to 2 m tall) and more upright than that of the female (whose dorsal fin is up to 1.2 m tall). The color of the saddle patch is of great interest, white indicates it is from the northern hemisphere, grey from the southern.

When do they breed and what size are they at birth?
Killer whale breeding occurs mostly in the winter to early spring while near the surface and in warm waters. The gestation period is about 16-17 months and the calf is born tail first (this is normal for cetaceans) and near the surface, usually between October and March. The newborn instinctively swims to the surface within 10 seconds for its first breath; it is helped by its mother, using her flippers. Within 30 minutes of its birth the baby whale can swim. The newborn calf is about 2 - 2.5 m. long, weighing up to 180 kg. Twins are extremely rare. The baby is nurtured with its mother's milk. The mother and calf stay together until maturity, which female killer whales reach at 10-15 years, and males at 12-16 years. The first born male calf stays with his mother as her companion for life.

How long do Killer Whales live?
Male killer whales have a life expectancy of 50-60 years. Females have a life expectancy of 80-90 years.

What do they eat?
Killer whales are efficient hunters that eat a very diverse diet of fish, squid, sharks, marine mammals (including whales and seals), turtles, octopi, and birds (penguins and gulls). They have even been known to attack blue whales and other large baleen whales. They have 10-13 pairs of large, interlocking conical, enameled teeth distributed in BOTH the upper and lower jaws (for a total of 20 to 26 pairs, so the killer has from 40 to 52 teeth). The teeth curve inwards and backwards - this helps the killer catch its prey. Teeth average about 7.5 cm long and about 2.5 cm in diameter, but some are even longer. Members of a pod frequently cooperate in hunts. An average-sized killer will eat 250 kg of food a day.

How deep do Killer Whales dive?
Killer whales can dive to a depth of 30 m in order to hunt. Killers commonly breach (swim at very fast speeds toward the surface in order to rise above it and then fall back again). Spy-hopping (poking its head out of the water to look around) and lob-tailing (slapping its tail on the water) are also common activities.

Do Killer Whales communicate?
Killer whale vocalizations include clicks, as used in echolocation, whistles, and scream-like pulses. The sounds are used to communicate with other killers, for mating purposes, and for locating prey. Different pods (long-lasting groups of killers) have distinctive "accents" and can recognize members by this accent.

How fast do they swim?
Killer whales are very fast swimmers. They can swim up to 50 km in bursts in order to catch prey.

Do Killer Whales migrate?
Killer whales don't make long, seasonal migrations. They may, however, cover an area of hundreds kilometres in order to find seasonal prey.

What is their habitat?
Killer whales live in waters ranging from tropics to the polar ice caps, and both coastal and deep oceanic waters. They are found in all the world's oceans and most of the seas. Killers sometimes enter estuaries, but don't go far from the sea. The species is in no danger as their numbers are abundant.