The dusky dolphin is a small cetacean that belongs to the Delphinidae family and the genus Lagenorhynchus, which also includes other five species.

It has a distribution limited to the southern hemisphere of the planet, with subpopulations scattered throughout the southeast and southwest Atlantic and Pacific oceans, including waters of Tasmania, southern Australia, New Zealand, the Chatham and Campbell Islands, South America and the Falkland Islands.

It also dwells around oceanic islands such as Tristan da Cunha, a British archipelago in the South Atlantic. Some of the countries that have dusky dolphins in their waters are Australia, Argentina, Chile, New Zealand, Peru and South Africa.

They sometimes stay close to bottlenose dolphins, but there is no evidence of interaction between the two species, unlike Risso dolphins, with whom they share feeding areas or with common dolphins that show some social contact.

This dolphin stays close to the coast, but unlike others, the coasts where they inhabit do not have warm waters. It is common to observe this cetacean on continental platforms and slopes where the waters are cold, and the currents have low temperatures, more or less of 10 to 18 Celsius degrees. The observed range of this species suggests that it limits to depths less than 200 meters and about 200 nautical miles away from the coast.

Its range of distribution goes hand in hand with the habitat that can provide them a great abundance of prey, among which is the anchovy that is found very close to the surface in shallow waters, and benthic creatures such as squids, hake and various types of fishes.

The cold habitat in which it lives does not deter humans from harming this species. Years ago, its capture was very constant in New Zealand, Peru and Chile mainly. Now, this has diminished, but its population situation, and therefore, its current state of conservation, is unknown.

Oceanic dolphins are aquatic mammals, members of the family Delphinidae which is part of the infraorder Cetacea.

They are closely related to whales and porpoises which are also cetaceans.

According to some sources, there are 43 species of dolphins, 38 species of dolphins which belong to the family Delphinidae of oceanic dolphins and five species of river dolphins. However, during 2011 a new species, the Burrunan dolphin was discovered, increasing the number to 44.

Dolphin Species List

1. Long-Beaked Common Dolphin, Delphinus capensis
2. Short-Beaked Common Dolphin, Delphinus delphis
3. Bottlenose Dolphin, Tursiops truncatus
4. Indo-Pacific Bottlenose Dolphin, Tursiops aduncus
5. Northern Rightwhale Dolphin, Lissodelphis borealis
6. Southern Rightwhale Dolphin, Lissodelphis peronii
7. Tucuxi, Sotalia fluviatilis
8. Costero, Sotalia guianensi
9. Indo-Pacific Hump-backed Dolphin, Sousa chinensis
10. Indian humpback dolphin, Sousa plumbea
11. Atlantic Humpbacked Dolphin, Sousa teuszii
12. Atlantic Spotted Dolphin, Stenella frontalis
13. Clymene Dolphin, Stenella clymene
14. Pantropical Spotted Dolphin, Stenella attenuata
15. Spinner Dolphin, Stenella longirostris
16. Striped Dolphin, Stenella coeruleoalba
17. Rough-Toothed Dolphin, Steno bredanensis
18. Chilean Dolphin, Cephalorhynchus eutropia
19. Commerson’s Dolphin, Cephalorhynchus commersonii
20. Heaviside’s Dolphin, Cephalorhynchus heavisidii
21. Hector’s Dolphin, Cephalorhynchus hectori
22. Risso’s Dolphin, Grampus griseus
23. Fraser’s Dolphin, Lagenodelphis hosei
24. Atlantic White-Sided Dolphin, Lagenorhynchus acutus
25. Dusky Dolphin, Lagenorhynchus obscurus
26. Hourglass Dolphin, Lagenorhynchus cruciger
27. Pacific White-Sided Dolphin, Lagenorhynchus obliquidens
28. Peale’s Dolphin, Lagenorhynchus australis
29. White-Beaked Dolphin, Lagenorhynchus albirostris
30. Australian Snubfin Dolphin, Orcaella heinsohni
31. Irrawaddy Dolphin, Orcaella brevirostris
32. Melon-headed Whale, Peponocephala electra
33. Killer Whale (Orca), Orcinus orca
34. Pygmy Killer Whale, Feresa attenuata
35. False Killer Whale, Pseudorca crassidens
36. Long-finned Pilot Whale, Globicephala melas
37. Short-finned Pilot Whale, Globicephala macrorhynchus
38. Guiana dolphin, Sotalia guianensis

River Dolphins

1. Boto (Amazon River Dolphin), Inia geoffrensis
2. Chinese River Dolphin (Baiji), Lipotes vexillifer (considered functionally extinct)
3. Ganges River Dolphin, Platanista gangetica gangetica
4. La Plata Dolphin (Franciscana), Pontoporia blainvillei
5. Indus River Dolphin, Platanista gangetica minor

New Species

Burrunan Dolphin, Tursiops australis