Common Name: Dwarf Sperm Whale
General Description: This species is very similar to the Pygmy Sperm Whale K. breviceps, but smaller. The snout is shorter than the Pygmy Sperm Whale’s. The shape of the head changes with age. In young individuals the snout slopes downward to the front; in an older animal it is straight, giving it a squarish profile. The dorsal fin is taller than in the Pygmy Sperm Whale, more than five percent of the total body length, and positioned farther forward on the back. This has a broad base, and a concave trailing edge.
The colouration is similar to the Pygmy Sperm Whale— medium grey above, and paler below with a pink tinge. There is a pale bracket mark or “false gill” on the head, but it is much less curved than in the Pygmy Sperm Whale.
Like the Pygmy Sperm Whale, Dwarf Sperm Whales may appear wrinkled.They differ from the Pygmy in having several short, irregular creases or grooves on the throat.
Size: Adults, Dwarf Sperm Whales attain lengths of 2.7 m, and weights of about 210 kg. Calves at birth,1 m long.
Appearance At Sea: Dwarf Sperm Whales are mostly encountered at sea lying at the surface, ‘like so many logs afloat’. They are usually seen in groups of two to seven individuals.
Kogia sima,Dwarf sperm whale in Daman,Gujarat,India @ Dipani Sutaria
Found In: The Dwarf Sperm Whale is an animal of tropical and subtropical seas. It seems to live exclusively on or near continental shelves. It is believed to make prolonged dives for food, as species of fish and squid that are known to live at depths of more than 250 m have been found in the stomachs of Dwarf Sperm Whales.
Records from India: Apart from the type specimen obtained from near Visakhapatnam, there are records of the Dwarf Sperm Whale from Trivandrum.
Date : 28 February 1853
Details : Skull from “Madras” — type specimen of “Physeter (Euphysetes) simus” gifted by Sir Walter Elliot to the British Museum (Natural History).
References : De Silva, 1987; Jerdon, 1867
Date : [?]
Details : Recorded from Vizagapatam by Blanford.
References : De Silva, 1987
Date : [?]
Details : Skull gifted by the Superintendent, Trivandrum Museum to the British Museum (Natural History).
References : De Silva, 1987
Dwarf Sperm Whales have been sighted off the coasts of Sri Lanka, Pakistan and Oman. They have stranded in Pakistan and Sri Lanka. They are caught occasionally by net fisheries in Sri Lanka.
World Distribution: This species has been recorded off much of the eastern coast of North America, but only the southern part of its western coast, off South Africa, South Australia, Japan, Hawaii and Guam.
Could Be Confused With:There is a possibility of confusion with the Pygmy Sperm Whale Kogia breviceps, the Pygmy Killer Whale Feresa attenuata and the Melon-headed Whale Peponocephala electra.
Species : Dwarf Sperm Whale
Size : Up to 2.7 m long
Fin : Less than 30 cm high, with slightly concave trailing edge, strongly curved and usually set near midpoint of the body
Markings : White false gill marking on head
Flippers : Broad square flippers
Face : Flat face
Species : Pygmy Sperm Whale
Size : Up to 3.4 m long
Fin : Less than 20 cm high, usually set well back
Markings : White false gill marking on head which is more curved than in Dwarf Sperm Whale
Flippers : Short, broad flippers
Face : Conical head with blunt face
Species : Pygmy Killer Whale
Size : Up to 2.5 m long
Fin: 30-40 cm high, with a markedly concave trailing edge
Markings : No white markings visible
Flippers : Rounded flippers
Face : Long tapered face
Species : Melon-headed Whale
Size : Up to 2.7 m long
Fin : More than 40 cm high, with a notched and wavy trailing edge
Markings : White belly extending far enough up flank to be visible in water
Flippers : Pointed flippers
Face : Curved parrot-like face
Diagnostic Features: At sea, Tall, curved dorsal fin; white false gill marking on head.
Stranded Specimens: There may be seven to 13 pairs of teeth in the lower jaw. Unlike the Pygmy Sperm Whale, this whale may have up to three pairs of undeveloped teeth in the upper jaw as well. The teeth of this species are shorter and more slender than those of the Pygmy Sperm Whale.
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