Pygmy Sperm Whales
Pygmy sperm whales are porpoise-like in body shape, and robust, with a distinctive underslung jaw, not unlike sharks. They have a short rostrum and the skull is markedly asymmetrical. They are larger than dwarf sperm whales. Colouration in adults is dark bluish gray to blackish brown on the back with a light venter. On the side of the head, between the eye and the flipper, there is often a crescent-shaped, light-coloured mark often referred to as a "false gill". Teeth are only found in the lower jaw and are very sharp and thin, lacking enamel.
They do not approach boats but are known to lie quietly at the surface practically until touched which makes them very easy to approach. They are rather slow and sluggish and have no visible blow.
They live mostly beyond the edge of the continental shelf in tropical and temperate waters around the world, ranging from Nova Scotia, the Azores, The Netherlands, Miyagi on the east coast of Honshu, Hawaii, and northern Washington State to the Cape Province, the Tasman Sea, Islas Juan Fernández, and Chile, and Argentina. It appears to be relatively common off the southeastern coast of the USA and around southern Africa, south-eastern Australia, and New Zealand.
Large sharks and killer whales
It is suggested that they migrate further offshore in the colder time of the year. Less strandings in summer support this thesis, but ut has not been proved yet.
Social system/Group size
Usually seen solitary, although groups of up to six animals have been reported.
They suffer from pollution, noise and are often seen entangled in gillnet fisheries.
In areas where they frequently strand, members of the genus Kogia are considered to be one of the most common species to come ashore. While many large males strand, many Kogia strandings also consist of a female and small calf or a female that has given birth only recently.