Clymene Dolphin (Stenella clymene)
Status | Taxonomy | Species Description | Habitat | Distribution |
Population Trends | Threats | Conservation Efforts | Regulatory Overview |
Key Documents | More Info
 Clymene Dolphins (Stenella clymene) Photo: NOAA's Southeast Fisheries Science Center |
|
Did You Know? · This species is also called the "short- snouted spinner dolphin"; it sometimes spins when it jumps out of the water. |
|
 Clymene Dolphin (Stenella clymene) Photo: NOAA |
|
Status
MMPA - Clymene dolphins, like all marine mammals, are protected under the MMPA.
Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Delphinidae
Genus: Stenella
Species: clymene
Species Description
Clymene dolphins, sometimes known as the "short-snouted spinner dolphin," are relatively small delphinids. In 1981, Clymene dolphins were separated from the "long-snouted spinner dolphin" (Stenella longirostris) and classified as a distinct species. Recent genetic analysis suggests that this species of dolphin is more closely related to striped dolphin, and appears physically similar to both striped and spinner dolphins (Shirihai and Jarrett 2006).
They are about 6-6.5 ft (1.8-2 m) in length and weigh about 165-200 lbs (75-90 kg). The species has a robust, streamlined body with a moderately short beak and a tall, "falcate" "dorsal" fin located midway down its back. The rounded melon is separated from the beak by a distinct crease. These dolphins are recognized by a tricolored pattern on their sides that includes a dark gray cape, moderately gray flanks, and a white or pale gray underside. They also have distinct black lips that appear similar to a "moustache" and a line that extends across the top ridge of their beak.
Clymene dolphins are usually found in small social groups of fewer than 60-80 individuals, but have been occasionally seen in larger groups of up to several hundred animals (Jefferson et al. 2008). Within these social groups, they may be organized by sex. This species sometimes associates with other cetacean species such as common dolphins and spinner dolphins. Their swimming behavior is often described as acrobatic due to their frequent aerial activity, such as jumping and spinning. They have also been known to approach vessels to bowride.
During dives they feed on small mesopelagic fish (e.g, "myctophids") and cephalopods (e.g., squid). Feeding sometimes occurs at night when their prey vertically migrates towards the surface. They have 36-52 pairs of small conical teeth in each jaw that are useful for grasping prey.
Little is known about the reproduction of this species of dolphin. Clymene dolphins become sexually mature and begin breeding at about 6 ft (1.8 m) in length. Females give birth to a single calf that is about 2.5-4 ft (0.8-1.2 m) long and weighs around 22 lbs (10 kg). The estimated lifespan of this species is unknown.
Habitat
Clymene dolphins prefer deep, tropical, subtropical and warm temperate waters in the Atlantic Ocean. This species generally occurs in oceanic waters 820-16,400 ft in depth (250-5,000 m).
Distribution
Clymene dolphins have a widespread distribution throughout the warm waters of the equatorial Atlantic Ocean. Their distribution ranges from the northwestern Atlantic (New Jersey), Gulf of Mexico, Caribbean, and Brazil to West Africa (Mauritania to Angola).
Population Trends
For management purposes, Clymene dolphins inhabiting U.S. waters have been divided into two stocks: the Northern Gulf of Mexico stock and the Western North Atlantic stock. The Northern Gulf of Mexico stock is estimated at 10,500-17,500 while the population in the Western North Atlantic stock is estimated at 3,000-6,000 animals. There are insufficient data available on current population trends, but their abundance is thought to be naturally uncommon.
Threats
Clymene dolphins have been incidentally taken as bycatch in fisheries such as gillnets in Venezuela and possibly tuna purse seine nets off the coast of West Africa. They are also sometimes targeted and hunted by artisan whalers using harpoons in the Caribbean Sea.
Conservation Efforts
The International Union for Conservation of Nature and Natural Resources (IUCN's) Red List of Threatened Species 
considers this species "Data Deficient" due to insufficient information on population status and trends.
Regulatory Overview
This species is protected under the Marine Mammal Protection Act of 1972, as amended.
Key Documents
(All documents are in PDF format.)
| Title | Federal Register | Date |
|---|---|---|
| Stock Assessment Reports | n/a | various |
References:
- Jefferson, T. A, M. A. Webber, and R. L. Pitman. (2008). Marine Mammals of the World, A Comprehensive Guide to their Identification. Amsterdam, Elsevier. p. 238-240.
- Shirihai, H. and B. Jarrett (2006). Whales, Dolphins and Other Marine Mammals of the World. Princeton, Princeton University Press. p.184-186.
