Delphinus capensis

Saddleback Dolphin

Share this species with family and friends:

Saddleback Dolphin

 

Description

The Long-beaked common dolphin (scientific name: Delphinus capensis) is one of two species of common dolphin. Known for its long beak, this dolphin has the most teeth out of any dolphin in the world. Both species of common dolphin are extremely colorful, however, the long-beaked common is typically less brightly colored. In addition to slightly different coloring, beak size, and other physical characteristics; the long-beaked common dolphin differs from the short-beaked in that it prefers more shallow, warmer waters. Also, the long-beaked common dolphin is less abundant than the short-beaked common dolphin.

A marine mammal, the Long-beaked common dolphin is a member of the family Delphinidae, part of the order of cetaceans. Thie species name, capensis, was derived from the location of the original specimen for this dolphin, being found on the Cape of Good Hope in the early 1800s.

Long-beaked common dolphins have a rounded melon, moderately long beak, and a sleek but robust body with a high, pointed, falcate dorsal fin located in the mid portion of the back. This species can be identified by its distinct bright contrasting coloration patterns. There is a dull yellow/tan thoracic panel between the dark cape and white ventral patch forward of the dorsal fin. The bold coloration forms a crisscrossing hourglass pattern below the dark saddle, and a lighter gray area extends up to the tail stock.

Long-beaked common dolphins usually occur in sizable social groups ranging from 100 to 500 individuals, but have been occasionally seen in larger herds of thousands of individuals. These large schools are believed to consist of smaller sub-groups of 10 to 30 animals that are possibly related or separated by age and/or sex.

 

Sexual Dimorphism: Males are 5% larger than females.

Length:
Range: 2-2.5 m males; 1.9-2.2 m females

Weight:
Range: 135 kg

Geography

Long-beaked common dolphins generally occur within about 180 km of the coast. The overall distribution of this species remains imperfectly known, because until 1994, all common dolphins around the world were classified as a single species: D. delphis (Heyning and Perrin 1994).

There are two subspecies recognized:

D. c. capensis – This subspecies appears to be found in distinct areas and apparently-disjunct subpopulations are known from the east coast of South America, West Africa, southern Japan, Korea and northern Taiwan (and possibly China), central California to southern Mexico, Peru, and South Africa.

D. c. tropicalis – This subspecies ranges in the Indo-Pacific from at least the Red Sea/Somalia to western Taiwan/southern China and Indonesia, and including the Persian Gulf and Gulf of Thailand (Jefferson and Van Waerebeek 2002).

Ecosystem

Habitat and Ecology
Long-beaked common dolphins inhabit tropical and warm-temperate waters of all three major oceans. D. capensis seems to prefer shallower and warmer water and occurs generally closer to the coast than does D. delphis (Perrin 2002). It is found mostly over continental shelf water depths

Conservation

Although the species is widespread and its aggregate abundance probably numbers in the high tens or low hundreds of thousands, in several areas (most notably West Africa, the east and west coasts of South America and East Asia) there are known incidental and directed takes of unknown, but possibly large, magnitude, making it difficult to make a reliable assessment of the impact on the species. Therefore, the Long-beaked Common Dolphin is listed as Data Deficient

 

Threats

Major Threats
Long-beaked common dolphin are known to be taken in bottom-set gillnets and purse seine fisheries off southern California, but potential impacts are uncertain. Some bycatch has also been documented in drift gillnets off California (Carretta et al. 2005). They are only occasionally involved as bycatch in the eastern tropical Pacific tuna fishery. They are present off Japan, and some have been taken in drive fisheries there. There are anecdotal reports of potentially large numbers of dolphins, including long-beaked common dolphins, killed for bait in some coastal fisheries off Baja California, Mexico (K. Forney pers. comm.). Long-beaked common dolphins have been taken opportunistically by harpoon in northeastern Taiwan and are caught incidentally by oceanic driftnets off eastern Taiwan (J. Wang pers. comm.). There is a large direct kill around Margarita Island, off eastern Venezuela, in which dolphins are harpooned in large numbers (Romero et al. 2001). In the Indian Ocean and Chinese waters, they are taken in gillnets, trawls, and purse seines. There is growing concern about the large numbers of long-beaked common dolphins killed off Peru and used for human food or shark bait (K. Van Waerebeek pers. comm.). Incidental catches of Delphinus sp. in pelagic driftnets in southern and south-eastern Brazil have been recorded (Zerbini and Kotas 1998), but no current estimates of bycatch are available. Given that this fishery occurs in the presumed range of the species, some of these individuals may belong to this species.

View Source Articles & Credits on EOL

 

Friend a Species
Supporting Ambassadors
  • Yo Yoshida
  • Roger Voisinet
Image Credits
  • Southwest Fisheries Science Center, NOAA Fisheries Service