irrawaddy dolphins

Size comparison against an average human Conservation status

Vulnerable (IUCN 3.1)[1] Scientific classification Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Cetacea

Family: Delphinidae

Genus: Orcaella

Species: O. brevirostris

Binomial name Orcaella brevirostris

Owen in Gray, 1866[2]

Orcaella genus range map

See: Irrawaddy Dolphin

Geographic Range Map

The Irrawaddy Dolphin (Orcaella brevirostris) is a euryhaline species of Oceanic dolphin found in discontinuous sub-populations near sea coasts and in estuaries and rivers in parts of the Bay of Bengal and Southeast Asia. Contents [hide] 1 Etymology and Taxonomic History 2 Description 2.1 Reproduction 2.2 Behavior 3 Habitat and sub-populations 4 Interaction with Humans 5 Threats 6 Conservation 7 References 8 Bibliography 9 External links //

Etymology and Taxonomic History

The Irrawaddy Dolphin was first described by Sir Richard Owen in 1866 based on a specimen found in 1852, in the harbour of Visakhapatnam on the east coast of India.[3]It is one of two species in its genus. It has sometimes been listed variously in a family containing just itself and in Monodontidae and in Delphinapteridae. There is now widespread agreement to list it in the Delphinidae family.

Genetically the Irrawaddy Dolphin is closely related to the Orca. The species name brevirostris comes from the Latin meaning short-beaked. In 2005, genetic analysis showed that the Australian Snubfin Dolphin found at the coast of northern Australia forms a second species in the Orcaella genus.

Overall grey to dark slate blue, paler underneath. No distinctive pattern. Dorsal fin small and rounded behind middle of back. Forehead high and rounded; beak lacking. Broad rounded flippers. The similar species that can be found in Borneo is the Finless Porpoise, Neophocaena phocaenoides, is similar and has no back fin: the Humpback Dolphin, Sausa chinensis, is larger, has longer beak and larger dorsal fin.[3]

The several common names for Orcaella brevirostris (Latin) include: English: Irrawaddy dolphin, Local Chilika dialect: Baslnyya Magaror Bhuasuni Magar (oil yielding dolphin), Oriya: Khem and Khera

[3], French: Orcelle, Spanish: Delfín del Irrawaddy, German: Irrawadi Delphin, Burmese: Labai, Indonesia: Pesut, Malay: Lumbalumba, Khmer: Ph’sout, Lao: Pha’ka and Filipino: Lampasut.[4] In Thai, one of its names is pía loma hooa baht, because its rounded head is thought to resemble the shape of a Buddhist monk's bowl, a hooa baht.[5]

Description

Irrawaddy dolphins are similar to dogs, they like having their bellies rubbed and they learn tricks easily. Though most closely related to the Orca. This species has a large melon and a blunt, rounded head. Its beak is indistinct. The dorsal fin, located about two-thirds posterior along the back, is short, blunt and triangular. The flippers are long and broad. It is lightly coloured all over, but slightly more white