Long-Beaked Common Dolphin (Delphinus capensis)
Status | Taxonomy | Species Description | Habitat | Distribution |
Population Trends | Threats | Conservation Efforts | Regulatory Overview |
Key Documents | More Info
 Long-Beaked Common Dolphin (Delphinus capensis) Photo: NMFS Southwest Fisheries Science Center |
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Did You Know? · The species name capensis refers to the Cape of Good Hope. The type specimen for this species was collected there in the early 19th century (Reeves et al. 2002). |
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Status
MMPA - Long-beaked common dolphins, like all marine mammals, are protected under the MMPA.
Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Delphinidae
Genus: Delphinus
Species: capensis
The short-beaked common dolphin (Delphinus delphis) is another species of common dolphin.
Species Description
Long-beaked common dolphins are relatively small dolphins that can reach lengths of 6-8.5 ft (1.9-2.6 m) and weigh 160-500 lbs (80-235 kg). Males are slightly larger than females.
Long-beaked common dolphins have a rounded melon, moderately long beak, and a sleek but robust body with a tall, pointy, "falcate" dorsal fin located in the middle 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. Narrow dark stripes extend from the lower jaw to the flipper and from the eye to the anal area. The coloration and patterns of young and juvenile dolphins are muted and darker. Morphologies can be distinct and vary by geographic and regional areas.
The short-beaked common dolphin is another species of common dolphin that appears very similar to the long-beaked common dolphin. Both species are within the same genus, Delphinus, and in some areas their distribution overlaps. The two species differ slightly in physical size, features, coloration, and pattern. Short-beaked common dolphins generally prefer deeper and cooler waters farther from the coast when compared to long-beaked common dolphins. There is a distinct tropical population/subspecies of long-beaked common dolphins in the Indian Ocean and Southeast Asia region called Delphinus capensis tropicalis.
Long-beaked common dolphins are usually found in large social groups averaging from 100-500 animals, but have been occasionally seen in larger herds of thousands of individuals. These large schools are thought to consist of smaller sub-groups of 10-30 animals that are possibly related or separated by age and/or sex. These gregarious, energetic dolphins are commonly seen swimming rapidly, "breaching", "porpoising", and frequently engaging in other surface active behavior. They will often approach ships to "bowride" for long periods of time.
Long-beaked common dolphins are capable of diving to at least 900 ft (280 m) and holding their breath for up to 8 minutes to feed on prey. The majority of their diet consists of small schooling fish (e.g., anchovies, hake, pilchards, and sardines), krill and cephalopods (e.g., squid). Dolphin groups may work together to herd schools of prey. This species has 47-67 pairs of small sharp conical teeth in each jaw used for grasping prey.
Long-beaked common dolphins become sexually mature at around 6.5 ft (2 m) in length (Jefferson et al. 2008). Breeding usually takes place between the spring and autumn, followed by a 10-11 month gestation period. Females give birth to a single calf that is about 2.5-3 ft (0.8-1 m) long and weighs about 20 lbs (10 kg), and have an estimated calving interval of 1-3 years. These dolphins have an estimated lifespan of approximately 40 years.
Habitat
Long-beaked common dolphins generally prefer shallow, tropical, subtropical and warmer temperate waters closer to the coast (usually within 50-100 nautical miles (90-180 km)) and on the continental shelf.
Distribution
Long-beaked common dolphins have a restricted distribution in the Atlantic, Indian and Pacific Oceans. Long-beaked common dolphins are commonly found along the U.S. west coast, from Baja California (including the Gulf of California) northward to about central California. They are not known to occur along the U.S. Atlantic coast. Distinct populations can be found off the coasts of California and Mexico, South America (Peru, Chile, Venezuela, Brazil, and Argentina), West Africa, South Africa, Madagascar, the Arabian Peninsula, India, Indonesia, China, Korea, and southern Japan. The abundance and distribution of this species may change with varying oceanographic conditions.
Population Trends
For management purposes, long-beaked common dolphins inhabiting U.S. waters have been placed in a single California Stock. Currently, it is estimated that there are 25,000-43,000 animals off the U.S. coast of California. There are estimated to be 15,000-20,000 off of eastern South Africa (Shirihai and Jarrett 2006). Long-beaked common dolphins are not as abundant as short-beaked common dolphins, but they are not considered threatened or endangered.
Threats
Long-beaked common dolphins have been incidentally taken as bycatch in a number of fisheries that include driftnets, gillnets, purse seines, and trawls. A small number of animals have been killed for food and bait in the Caribbean, South America (e.g., Peru), West Africa, and other offshore islands. They have been taken in the Japanese drive fisheries as well.
Conservation Efforts
The International Union for Conservation of Nature and Natural Resources (IUCN's) Red List of Threatened Species 
considers this species "Low Risk Least Concern."
In 1997, NMFS implemented the Pacific Offshore Cetacean Take Reduction Plan, which requires the use of pingers (an acoustic deterrence device) and 6-fathom net extenders in the CA/OR drift fishery to reduce bycatch of cetaceans, including long-beaked common dolphins. The Pacific Offshore Cetacean Take Reduction Team continues to meet and recommend measures to further reduce bycatch and achieve MMPA goals.
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 |
| Pacific Offshore Cetacean Take Reduction Plan (POCTRP) | 62 FR 51805 | 10/03/1997 |
- NMFS Southwest Fisheries Science Center Common Dolphin Information
- NOAA's National Marine Sanctuaries
References:
- Reeves, R. R., P. A. Folkens, et al. (2002). Guide to Marine Mammals of the World. New York, Alfred A. Knopf. p. 392-394.
- 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. 249-252.
- Shirihai, H. and B. Jarrett (2006). Whales, Dolphins and Other Marine Mammals of the World. Princeton, Princeton University Press. p. 174-176.
