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| Ecology and Behavior |
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Habitat: Continental slope/oceanic
Striped dolphins are fast swimmers, and tend to be more easily alarmed than other tropical dolphins; this and their color pattern have prompted fishermen to call them "streakers." Although most herds number between 100 and 500 individuals, striped dolphins sometimes assemble into herds of thousands. At least off Japan, there appears to be some age/sex segregation of such herds.
Reproduction:
Off Japan, where the biology of this species has been best studied, there are two calving peaks one in summer, another in winter. Newborns are about 1 m in length. |
| Feeding and Prey |
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Feeding mode: Seizing
Broad diet dominated by: Squid > fish > other invertebrates
The diet of this species consists primarily of small, midwater squid and fish, especially lanternfish.
Known prey species:
Notoscopelus kroyeri, Xenodermichthys copei, Merluccius merluccius, Micromesistius poutassou, Belone belone, Boops boops, Engraulis encrasicholus, Stomias boa, Chauliodus sloanei, Maurolicus muelleri, Hygophum sp., Diaphus rafinesquei, Diaphus sp., Lobianchia gemellarii, Lampanyctus crocodilus, Lampanyctus sp., Ceratoscopelus maderensis
Cephalopods: Sepietta oweniana, Heteroteuthis dispar, Neorossia caroli, Sepiolidae sp., Loligo forbesi, Alloteuthis media, Onychoteuthis banksii, Ancistroteuthis lichtensteini, Histioteuthis bonnellii, Histioteuthis reversa, Illex coindetii, Todaropsis eblanae, Todarodes sagittatus, Scaeurgus unicirrhus
Invertebrates:Acantephyra sp., Sergestes sp., M. norvegica, Pasiphaea multidentata, Acanthephyra pelagica, Sergia robusta |
| Threats and Status |
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Main threats include:
Harvest
Fisheries bycatch
Conservation status:
The IUCN lists the striped dolphin as lower risk/conservation dependent. In the U.S., striped dolphins are not listed as threatened or endangered. Striped dolphins are the main delphinid species involved in small cetacean harpoon and drive fisheries in Japanese waters. Although catches vary widely, in past years they were over 20,000. This species has also been directly captured in the Caribbean, Sri Lanka, and occasionally in the Mediterranean. Incidental catches occur throughout the range in various types of fishing gear, especially purse seines and driftnets. Large numbers of this species were formerly caught in pelagic driftnets in the Mediterranean and in North Pacific. A massive die-off in the Mediterranean is thought to have been at least partly related to environmental contaminants.
NMFS has estimated the size of several populations of striped dolphins. The western North Atlantic population, from Florida to the Gulf of St. Lawrence, was estimated in 1998 to be 61,546 (CV=0.40). The northern Gulf of Mexico stock was estimated using data from 1991-1994 to be 4,858 (CV=0.44). The California/Oregon/Washington stock was estimated using data from 1991-1996 to be 20,235 (CV=0.14). Estimates for the eastern tropical Pacific have been made for several recent years, the lowest in 1986, being 801,210 (CV=0.191) and the highest in 1988, being 1,497,428 (CV=0.139).
For current information on the conservation status of this species, please consult the following websites.
CITES web-page
International Whaling Commission
U.S. NMFS Stock Assessment Reports
Convention on Migratory Species (Appendix II, eastern tropical Pacific and western Mediterranean populations) |
| References |
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Aguilar, A., and J.A. Raga. 1993. The striped dolphin epizootic in the Mediterranean Sea. Ambio 22:524-528.
Archer, F.I. 2002. Striped dolphin Stenella coeruleoalba. Pp. 1201-1203 in W.F. Perrin, B. Würsig and J.G.M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.
Archer, F.I., and W.F. Perrin. 1999. Stenella coeruleoalba. Mammalian Species 603:1-9.
Calzada, N., A. Aguilar, C. Lockyer, and E. Grau. 1997. Patterns of growth and physical maturity in the western Mediterranean striped dolphins, Stenella coeruleoalba (Cetacea Odontoceti). Canadian Journal of Zoology 75:632-637.
Hassani, S., L. Antoine, and V. Ridoux. 1997. Diets of albacore, Thunnus alalunga, and dolphins, Delphinus delphis and Stenella coeruleoalba, caught in the Northeast Atlantic albacore drift-net fishery a progress report. Journal of the Northwest Atlantic Fisheries Science 22 119-123.
Miyazaki, N. 1984. Further analyses of reproduction in the striped dolphin, Stenella coeruleoalba, off the Pacific coast of Japan. Reports of the International Whaling Commission Special Issue 6:343-353.
Perrin, W.F., C.E. Wilson, and F.I. Archer III. 1994. Striped dolphin Stenella coeruleoalba (Meyen, 1833). Pp. 129-159 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Volume 5 The first book of dolphins. Academic Press.
Wurtz, M. and D. Marrale. 1993. Food of the striped dolphin, Stenella coeruleoalba, in the Ligurian Sea. Journal of the Marine Biological Association of the United Kingdom 73571-578.
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