Whales

The cetaceans include both the baleen and toothed whales, however the term whale tends not to be associated with the dolphins which fall under the toothed whale umbrella.

Humpback Whale
Sperm whale underwater

Sperm whale underwater

Classification

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Subclass: Eutheria
Order: Cetacea

Species

Toothed whales are active hunters, eating fish, squid and other mammals among others. Baleen whales use their thick baleen comb to filter micro-organisms and shoals of fish from large mouthfuls. Toothed whales have one blow hole while baleen whales have two.

Examples of toothed whales include sperm whales, belugas, narwhals and dolphins. Examples of baleen whales include blue whales, humpbacks and minke whales.

Communication

Whales communicate using a series of clicks and whistles, which their water medium can carry over huge distances. Some whales have also adapted this for echolocation, using an organ in the head to focus the sound and listen for returning echoes.

Size

Blue whales are the largest animal ever to populate the planet.

Hunting

Sperm whales actively hunt squid at great depths. As they eat the squid whole they need to ease their passing of the indigestible beaks by covering them in a thick liquid. This ambergris is used in perfumery to hold in the scent.

Humpback whale breaching

Humpback whale breaching

Behaviour

Humpback whales can be seen breaching spectacularly during the mating season. They can almost leap completely out of the water, coming down with an almighty splash.

Threats

Whales are in decline worldwide, mostly attributed to loss of available food and the actions of man. Some countries still actively hunt whales, a process called whaling, although some indigenous tribes do this in a sustainable fashion.

Whales are thought to be disturbed by naval sonar and this has been implicated in some beachings. However, recent evidence has suggested that whales can regulate their hearing, but this does not rule out discomfort from this noise.