Absolute Dolphins

The Dusky dolphin was named its scientific name Obscurus Latin for "indistinct", describing its unique appearance. A small and compact dolphin, its beak is short and its forehead slopes gently. The dorsal cape of its shoulders ranges from a dark grey to a blue black with a slight increase of light grey on the rear of the dorsal fin, and the flippers are dark. White or grey brightly marks its undersides and flanks, and each eye is encircled with a small dark patch. It can commonly be confused with the Peale's dolphin, and the Hourglass dolphin, but the latter is strikingly black and white only.

Preferring the inshore coastal regions, Duskies inhabit the temperate waters of South Africa, New Zealand and South America.

Adult length: Duskies are smaller dolphins, and their size as adults range from 1.6 metres and 2.1 metres in length.

Habitat: Coastal waters, and inshore temperate regions are where Dusky dolphins prefer to live. They are found in New Zealand, South America and South Africa.

Group size: A dusky's pod can range from small units of 6 to 15 numbers to larger groups of 6 to 500. Massive groups of over 1,000 can also occur though the former numbers are more common. The largest gatherings of this species are generally found in the summertime.

Behaviour: Dusky's are highly social and extremely acrobatic, leaping, spinning, somersaulting and bowriding. Associations with Common dolphins and Southern Right Whales are common. Even seabirds such as albatrosses and petrels have been seen to join the Dusky's pods. A highly inquisitive animal, the Dusky dolphin is usually easy to approach and appears to enjoy contact with boats as well as people. They love to ride bow waves and leap a dozen times in a row. Interestingly, when one dolphin starts jumping and frollicking, the rest of the group will join in also.

Reproduction: Gestation is thought to last between 9 and 11 months. In New Zealand, birth occurs during winter from June to August, though in Argentina birth takes place in the summer months. Females have only a single baby every two to three years.

Calves: Newborn calves weigh around 5 kg and eat anchovies and squid. Females will attain sexual maturity when they reach 1.65 metres.

Diet & Feeding: The Dusky mostly feeds on a variety of deep sea fish such as octopus, anchovies, and squid. The dusky pod will work together to herd fish into a tightly packed group near the surface, so the fish cannot escape. The dolphins then charge into the school, with the fish panicking, making them easy to catch.

Noteable features: The Dusky is a quick and energetic swimmer. It surfaces four to five times per minute to breathe, for 5 to 13 seconds. They follow ships going at a speed of 29.5 to 32.5 km per hour, and can reach depths of 150 metres. These cetaceans groups by age. Along the coast of Argentina the Dusky dolphin's behaviour changes from day to night - where during the day it is active and looks for food, but once night falls it becomes lethargic. Mass strandings of the Dusky dolphin in New Zealand have also ben observed.

Threats: Dusky dolphins are accidentally caught in Argentinean drift nets during October and November, and also in fishing tackle in New Zealand. Peru also culls around 700 each year with the meat being sold on the food market. They are also fished by net or harpoon for human consumption in South Africa. A few of these dolphins have also been caught for aquariums in New Zealand and South Africa. It is unknown as to how many remain. Duskies in captivity don't appear to survive well, with only low to moderate success.

Population: Numbers are unknown.

Other Dusky Dolphin Facts:

The adult's body is very spindle shaped, with a short rounded snout.

The flukes are small compared to the rest of the body.

Generally dark grey on the back and white on the stomach, with a large grey area at the bottom of the flanks.

Duskies have about 24 to 36 pairs of small teeth

Duskies travel to the north of New Zealand in April to mate and give birth, returning to the south with its offspring in October.

Duskies seem to invite the company of other species as well as those of their own species.

Duskies make violent water slaps to heard its prey.

Interesting Dusky Dolphin Facts:

A Dusky may make 40 to 50 acrobatic leaps one after the other.

Duskies closely resemble their cousins , the Pacific White-Sided dolphin (Lagenorhynchus obliquidens) although they don't inhabit the same waters.