The Clymene Dolphin (Stenella clymene), in some texts known as the Short-snouted Spinner Dolphin, is dolphin endemic to the Atlantic Ocean.

Taxonomy

From its discovery by John Gray in 1850 until a re-assessment in 1981, the Clymene Dolphin was regarded as sub-species of the Spinner Dolphin. In 1981 Perrin et al asserted the Clymene's existence as separate species. Up until this time, because Clymenes are relatively remote and regarded as "the same" as more accessible Spinners they were never heavily studied. Mead and Perrin went some way to redress this balance but the Clymene Dolphin is still one of the least understood of all cetaceans.

Physical description

The Clymene Dolphin looks very similar to the Spinner Dolphin and at sea, where the two species may intermingle in large groups, they may be indistinguishable. At close quarters it is possible to observe that the beak of the Clymene is slightly shorter that its relative. The dorsal fin is also less erect and triangular.

The basic colour of the Clymene Dolphin is "cetacean neapolitan" - it comes in three shaded layers - the underside being a white-pink colour. Next comes a strip of light grey that runs from just above the beak, round either side of the eye all the way back to the tail stock where the band thickens. The top layer, from the forehead, along the back to the dorsal fin and down to the top of the tail stock is a dark grey. The beak, lips and flippers are also dark grey in colour.

Clymene Dolphins grow to about two metres in length and 75-80kg in weight. No figures are available for the size of animals at birth. Gestation, lactation, maturation and longevity periods are all unknown but are unlikely to vary greatly from others in the Stenella genus.

Clymenes are fairly active dolphins. They do spin longitudinally when jumping clear of the water, but now with as much regularity and complexity as the Spinner Dolphin. They will also approach boats and bow-ride. Diet is likely to consist of small fish and squid. Group sizes vary from just a few individuals to great schools numbering upto 500.

Population and distribution

The Clymene Dolphin is endemic to the Atlantic Ocean. Its full range is still poorly understood, particular at its southern end. The species certainly prefers temperate and tropical waters. The northern end of the range runs approximately from New Jersey east-south-east to southern Morocco. The southern tips runs from somewhere around Angola to Rio de Janeiro. They appear to prefer deep water. Plenty of sightings have been recoreded in the Gulf of Mexico. The species has not been sighted however in the Mediterranean Sea.

Total population is unknown. The only population estimate available is for the north part of the Gulf of Mexico, where a count of 5,500 individuals was reported. The species may be naturally rare in comparison with others in the Stenella genus.

Human interaction

The species has not had much interaction with humans. Some individuals have been killed from directed fisheries in the Caribbean and others in nets off West Africa.

References

1. Stenella clymene, a rediscovered tropical dolphin of the Atlantic, Perrin, Mitchell, Mead, Caldwell and van Bree (1981) Journal of Mammology. Vol 62, pp 583-589.
2. Clymene Dolphin Perrin and Mead in Handbook of Marine Mammals. Vol 5. pp 161-171.
3. Clymene Dolphin by Thomas A. Jefferson in Encyclopedia of Marine Mammals pp. 234-236. ISBN 01255513402
4. Whales Dolphins and Porpoises, Mark Carwardine, Dorling Kindersley Handbooks, ISBN 0751327816
5. National Audubon Society Guide to Marine Mammals of the World, Reeves, Stewart, Clapham and Powell, ISBN 0375411410