Delphinus capensis (Gray, 1828)

English: Long-beaked common dolphin
German: Cape-Delphin, Gewöhnlicher Delphin mit langem Schnabel
Spanish: Delfín común a pico largo
French: Dauphin commun a bec large

Family: Delphinidae


Delphinus capensis © Wurtz-Artescienza (see links).


1. Description

Until 1994 all common dolphins were classified as a single species, D. delphis, but research by Heyning and Perrin (1994), later confirmed by Kingston and Rosel (2004), led to the recognition of two distinct species: the long-beaked and the short-beaked common dolphins.

The taxonomic status of D. capensis has been further clarified in a morphometric study (Jefferson and Van Waerebeek 2002) The authors suggest that the Indian Ocean form called by some Delphinus tropicalis (as reviewed in van Bree and Gallagher, 1978) is actually a long-beaked subspecies of D. capensis, which may hybridize or intergrade with the standard capensis-form in Southeast Asia and possibly along the east coast of Africa. The appropriate name is Delphinus capensis tropicalis (van Bree, 1971).

D. capensis may be difficult to distinguish from D. delphis, especially at sea. Its body is more slender and it has a longer beak than the short-beaked common dolphin. The beak is sharply demarcated from the melon, which is somewhat flat in appearance. The coloration is somewhat muted and the chin-to-flipper stripe, which often merges with the lip patch, thus darkening the lower jaw, is broader. In addition, white is absent from the dorsal fin and flippers (occurs in some short-beaked common dolphins). There are 47-67 sharp pointed teeth in each tooth row, more than in any other delphinid. Body size reaches 2.54 m and body mass 235 kg (Jefferson et al. 2008).



Detail of Delphinus capensis © Michelle Berman, Santa Barbara

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2. Distribution

Disjunct populations of D. capensis are found in warm temperate and tropical coastal waters around the world. The overall distribution remains imperfectly known because of past confusion with D. delphis (Rice, 1998; Sanino et al., 2003).

D. c. capensis -occurs in the Atlantic and Pacific Oceans on 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 (Hammond et al. 2008). However, Bernal et al. (2003) report on the long-term residency of two long-beaked common dolphins in two small bays off the central coast of Chile, extending the eastern South Pacific range southward by 800 nm.


Distribution of Delphinus capensis: disjunct populations in warm temperate and tropical coastal waters (Hammond et al. 2008; © IUCN; Click here for large map).

D. c. tropicalis - 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 (Hammond et al., 2008).

Beware that some authors have haphazardly applied the name D. bairdii or D. delphis bairdii to all Pacific Ocean Delphinus (Rice, 1998).

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3. Population size

There is no estimate of global abundance for D. capensis and few local abundance estimates. The distribution and abundance of long-beaked common dolphins off California appears to be variable on interannual and seasonal time scales (Heyning and Perrin 1994). As oceanographic conditions change, long-beaked common dolphins may spend time in Mexican waters, and therefore a multi-year average abundance estimate is the most appropriate for management within the U.S. waters. The most recent estimate of abundance in waters of California, Oregon and Washington is 15, 334 (Barlow and Forney, 2007). Gerrodette and Palacios (1996) estimated 55,000 within Pacific coast waters of the Mexican EEZ and 69,000 in the Gulf of California. About 15,000-20,000 are estimated to occur off South Africa. The tropicalis subspecies is widespread in the Indian and western Pacific oceans, but there are no estimates of abundance for any portion of its range Hammond et al. (2008).

Photograph by courtesy of Clinton Bauder, Metridium Fields (see "links").back to the top of the page


4. Biology and Behaviour

Habitat: D. capensis seems to prefer shallower and warmer water and occurs generally closer to the coast than D. delphis (Perrin, 2009). It is found mostly over continental shelf water depths (< 180 m), and generally does not occur around oceanic islands far from mainland coasts (Jefferson and Van Waerebeek 2002, Sanino et al. 2003).

Food: Off Brazil, D. capensis seems to prefer cephalopods (De Oliveira Santos et al. 2002). D. capensis off southern California feeds on sardines (Sardinops coerulea), anchovies (Engraulis mordax), sauries (Cololabis saira), small bonitos (Sarda chiliensis), and squids (Loligo opalescens). Long-beaked common dolphins off southern Africa feed mainly on pilchards (Sardinops ocellatus), anchovies (Engraulis capensis), and squids (Loligo v. reynaudii) but had many other prey species of fishes and squids, including myctophids in their stomachs (Ohizumi et al. 1998). While these authors find that there seems to be no obvious difference in the diet between C. delphis and C. capensis, recent investigations on fatty acid composition of blubber tissue of animals from the coast of California show differences that seem to stem from dietary differences (Smith and Worthy, 2006). back to the top of the page


5. Migration

Unknown.back to the top of the page


6. Threats

Fisheries interactions: Miscellaneous lesions of the head, skull, teeth, trunk, appendages, skin and genital tract were observed in 120 of 930 long-beaked common dolphins taken in fisheries off Peru between 1985 and 2000. The majority of traumas encountered were diagnosed as caused by violent, fisheries-related interactions, and the skin in 20.4% of specimens (n = 54) showed healed scars from such interactions. There is concern that total fisheries-related dolphin mortality is thought to be higher than can be accounted for by the tallying of landed specimens. In Peru, long-beaked common dolphins were frequently captured by industrial purse-seiners, including in directed sets, at least until 1994. (Van Bressem et al. 2006).

Delphinus capensis © Parissa Yazdi, Hamburg


A total of 44 specimens were reported as incidental marine mammal bycatch in the California drift gillnet fishery for broadbill swordfish Xiphia gladius and common thresher shark, Alopias vulpinus, in the 7-year period, 1996 to 2002 (Carretta et al. 2004). Hammond et al. (2008) report that they are presently only occasionally involved as bycatch in the eastern tropical Pacific tuna fishery. 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.
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Long-beaked common dolphins have been taken opportunistically by harpoon in northeastern Taiwan and are caught incidentally by oceanic driftnets off eastern Taiwan. In the Indian Ocean and Chinese waters, they are taken in gillnets, trawls, and purse seines. They are present off Japan, and some have been taken in drive fisheries there. Incidental catches of Delphinus sp. in pelagic driftnets in southern and south-eastern Brazil have been recorded, but no current estimates of bycatch are available. There is a large direct kill around Margarita Island, off eastern Venezuela, in which dolphins are harpooned in large numbers (Hammond et al. 2008).

Pollution: Wide ranges of organochlorine residues were determined in the blubber of long-beaked common dolphin incidentally caught in Brazilian coastal waters (Kajiwara, 2004). Concentrations of DDTs and PCBs were the highest, followed by CHLs, TCPMOH, dieldrin, TCPMe, heptachlor epoxide, HCB, and HCHs. Unexpectedly, significant contamination by PCBs, DDTs, TCPMe, and TCPMOH was observed, implying the occurrence of local sources in the Southern Hemisphere comparable to those in the Northern Hemisphere, probably due to high industrialization in Brazil.back to the top of the page


7. Remarks

Range states :
Argentina; Brazil; Chile; China; Côte d'Ivoire; Djibouti; Egypt; Eritrea; Gabon; Guyana; Hong Kong; India; Indonesia; Iran, Islamic Republic of; Japan; Korea, Democratic People's Republic of; Korea, Republic of; Kuwait; Madagascar; Malaysia; Mauritania; Mexico (Baja California, Sinaloa, Sonora); New Zealand; Oman; Pakistan; Peru; Saudi Arabia; Senegal; South Africa; Sri Lanka; Sudan; Suriname; Taiwan, Province of China; Thailand; United Arab Emirates; United States (California); Uruguay; Venezuela; Viet Nam; Western Sahara; Yemen (Hammond et al. 2008).

Because of past confusion with D. delphis, very little is known about this species. Overall distribution, behaviour at sea, movements, reproduction and other key parameters, such as abundance, are poorly known. Threats are presumably similar to those affecting D.delphis. The lower density, however, could reflect that this species is not as abundant as D. delphis and thus could be more strongly affected by by-catch in fisheries. See further recommendations on South American stocks in Hucke-Gaete (2000) (see Appendix 1) and on Southeast Asian stocks in Perrin et al. (1996) (see Appendix 2).

D. capensis is categorized as "Data Deficient" by the IUCN. The species is listed in Appendix II of CITES. Not listed by CMS.

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8. Sources

Barlow J, Forney KA (2007) Abundance and population density of cetaceans in the California Current ecosystem. Fish. Bull., U.S. 105:509-526.
· Bernal R, Olavarria C, Moraga R (2003) Occurrence and long-term residency of two long-beaked common dolphins, Delphinus capensis (Gray 1828), in adjacent small bays on the Chilean central coast. Aquat. Mamm. 29: 396-399
. Bree PJH van (1971) Delphinus tropicalis, a new name for Delphinus longirostris Cuvier 1829. Mammalia 35: 345-346
· Bree PJH van, Gallagher MD (1978) On the taxonomic status of Delphinus tropicalis van Bree, 1971 (Notes on Cetacea, Delphinoidea IX). Beaufortia 28: 1-8.
· Carretta JV, Price T, Petersen D, Read R (2004) Estimates of marine mammal, sea turtle, and seabird mortality in the California drift gillnet fishery for swordfish and thresher shark, 1996-2002. Mar. Fish. Rev. 66: 21-30
· De Oliveira, Santos MC, Rosso S, Dos Santos RA, Lucato SHB (2002) Insights on small cetacean feeding habits in southeastern Brazil. Aquat. Mamm. 28: 38-45.
· Gerrodette T, Palacios DM (1996) Estimates of cetacean abundance in EEZ waters of the eastern tropical Pacific. SWFSC Admin. Rep. LJ-96-10, 28 pp.
· Hammond PS, Bearzi G, Bjørge A, Forney K, Karczmarski L, Kasuya T, Perrin WF, Scott MD, Wang JY, Wells RS , Wilson B (2008) Delphinus capensis. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1. <www.iucnredlist.org>
· Heyning JE, Perrin W F (1994) Evidence for two species of common dolphins (genus Delphinus) from the eastern North Pacific. Los Angeles County Mus. Nat. Hist. Contr. Sci. 442: 1-35.
· Hucke-Gaete R, ED. (2000) Review on the conservation status of small cetaceans in southern South America. UNEP/CMS Secretariat, Bonn, Germany, 24 pp.
· Jefferson TA, Van Waerebeek K (2002) The taxonomic status of the nominal dolphin species Delphinus tropicalis van Bree , 1971. Mar. Mamm. Sci. 18: 787-818
· Jefferson TA, Webber MA , Pitman RL (2008) Marine mammals of the world. Elsevier, Amsterdam, 573 pp.
· Kajiwara N, Matsuoka S, Iwata H, Tanabe S, Rosas FCW, Fillmann G, Readman JW(2004) Contamination by persistent organochlorines in cetaceans incidentally caught along Brazilian coastal waters. Arch. Environ. Contam. Toxicol. 46: 124-134
· Kingston SE, Rosel PE (2004) Genetic differentiation among recently diverged delphinid taxa determined using AFLP markers. J. Hered. 95: 1-10
· Li S (1997) Studies on sea mammals and its distribution from Fujian coastal waters. J. Oceanogr. Taiwan Strait; Taiwan Haixia 16: 479-485.
· Ohizumi H, Yoshioka M, Mori K, Miyazaki N (1998) Stomach contents of common dolphins (Delphinus delphis) in the pelagic western North Pacific. Mar. Mamm. Sci. 14: 835-844.
· Perrin WF (2009) Common dolphins. In: Encyclopedia of marine mammals 2nd Ed. (Perrin WF, Würsig B, Thewissen JGM, eds.) Academic Press, Amsterdam, pp. 255-259.
· Perrin WF, Dolar MLL, Alava MNR (1996) Report of the Workshop on the Biology and Conservation of Small Cetaceans and Dugongs of Southeast Asia. East Asia Seas Action Plan. UNEP(W)/EAS WG. 1/2, Bangkok, Thailand. 101 pp.
· Rice DW (1998) Marine mammals of the world: systematics and distribution. Society for Marine Mammalogy, Spec. Pub. 4, Lawrence, KS. USA.
· Sanino GP, Van Waerebeek K, Yanez J (2003) Revision de la distribucion del género Delphinus y registros documentados de Delphinus delphis en Chile. Bol. Mus. Nac. Hist Nat. (Chile) 52: 97-102.
· Smith HR, Worthy GAJ (2006) Stratification and intra- and inter-specific differences in fatty acid composition of common dolphin (Delphinus sp.) blubber: Implications for dietary analysis. Comp. Biochem. Physiol. B143: 486-499
· Van Bressem M-F, Van Waerebeek K, Montes D, Kennedy S, Reyes JC, Garcia-Godos IA, Onton-Silva K, Alfaro-Shigueto Joanna (2006) Diseases, lesions and malformations in the long-beaked common dolphin Delphinus capensis from the Southeast Pacific. Dis. Aquat. Org. 68: 149-165


© Boris Culik (2010) Odontocetes. The toothed whales: "Delphinus capensis". UNEP/CMS Secretariat, Bonn, Germany.http://www.cms.int/small-cetaceans
© Illustrations by Maurizio Würtz, Artescienza.
© Maps by IUCN.

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