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Home/Species/ Risso's Dolphin

Grampus griseus

(G. Cuvier, 1812)

Risso's Dolphin

G5Secure Found in 2 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
Identity
Unique IDELEMENT_GLOBAL.2.101302
Element CodeAMAGE08010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
CITESAppendix II
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassMammalia
OrderCetacea
FamilyDelphinidae
GenusGrampus
Other Common Names
Dauphin de Risso (FR) Dauphin gris (FR) Delfín de Risso, Delfín Gris (ES) Marsouin gris (FR)
Concept Reference
Wilson, D. E., and D. M. Reeder (editors). 1993. Mammal species of the world: a taxonomic and geographic reference. Second edition. Smithsonian Institution Press, Washington, DC. xviii + 1206 pp. Available online at: http://www.nmnh.si.edu/msw/.
Conservation Status
Rank MethodExpertise without calculation
Review Date2016-04-04
Change Date1996-11-15
Range Extent Comments
Not uncommon worldwide in tropical, subtropical, and warm temperate oceans. In the North Atlantic: Newfoundland to Lesser Antilles in the west, Sweden to the Mediterranean in the east. South to Argentina and South Africa in the south Atlantic. In the Pacific Ocean: Alaska and the Kuiles south to central Chile, Australia, and New Zealand. Occurs also in the Indian Ocean and Red Sea. May wander into cooler waters in summer. See Leatherwood et al. (1980) for information on distribution in the eastern Pacific Ocean.
Threat Impact Comments
Hunted only incidentally in small cetacean fisheries throughout the world (Leatherwood and Reeves 1983). The only known substantial threat is local--incidental take that occurs in association with the Sri Lankan gillnet fishery in the Indian Ocean (IUCN 1991).
Ecology & Habitat

Habitat

Pelagic waters; generally in water >180 m deep (>1000 m deep according to IUCN 1991). In the northern Gulf of Mexico, occurs mainly in steep sections of the upper continental slope, where water depth is 350-975 m and gradient is greater than 24 m per 1.1 km (Baumgartner 1997).

Ecology

Usually occurs in groups; off California, groups averaged usually between 30-50, sometimes over 200; in the eastern tropical Pacific, groups averaged 15-26; in the northeastern Atlantic and Mediterranean, average group size was 6-7, with maximum of 20-30 (Leatherwood et al. 1980, IUCN 1991). Commonly associates with pilot whales.
Other Nations (2)
CanadaN5
ProvinceRankNative
British ColumbiaS5Yes
United StatesNU
ProvinceRankNative
OregonSNAYes
North CarolinaSNAYes
HawaiiSNAYes
FloridaSNRYes
MassachusettsS3Yes
MarylandSNAYes
New YorkSNRNYes
South CarolinaS4Yes
Threat Assessments
ThreatScopeSeverityTiming
5 - Biological resource use——High (continuing)
5.4 - Fishing & harvesting aquatic resources——High (continuing)
9 - Pollution——High (continuing)
9.6 - Excess energy——High (continuing)
11 - Climate change & severe weather——Moderate - low
11.1 - Habitat shifting & alteration——Moderate - low

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Roadless Areas (2)
Alaska (2)
AreaForestAcres
Game CreekTongass National Forest54,469
GravinaTongass National Forest37,381
References (18)
  1. American Society of Mammalogists (ASM). 2025. Mammal Diversity Database (Version 1.13) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.10595931. Online. Available: https://www.mammaldiversity.org/
  2. Banfield, A. W. F. 1974. The mammals of Canada. University of Toronto Press, Toronto, Canada. 438 pp.
  3. Baumgartner, M. F. 1997. The distribution of Risso's dolphin (<i>Grampus griseus</i>) with respect to the physiography of the northern Gulf of Mexico. Marine Mammal Science 13:614-638.
  4. Bradley, R.D., L.K. Ammerman, R.J. Baker, L.C. Bradley, J.A. Cook. R.C. Dowler, C. Jones, D.J. Schmidly, F.B. Stangl Jr., R.A. Van den Bussche and B. Würsig. 2014. Revised checklist of North American mammals north of Mexico, 2014. Museum of Texas Tech University Occasional Papers 327:1-28. Available at: http://www.nsrl.ttu.edu/publications/opapers/ops/OP327.pdf
  5. Folkens, P. 1984. The whale watcher's handbook. Doubleday Co., Inc., Garden City, NY 208 pp.
  6. Godin, A. J. 1977. Wild mammals of New England. Johns Hopkins University Press, Baltimore. 304 pp.
  7. Gubbins, C. 2002. Use of home ranges by resident bottlenose dolphins (<i>Tursiops truncatus</i>) in a South Carolina estuary. Journal of Mammalogy 83: 178-187.
  8. Hall, E. R. 1981a. The Mammals of North America, second edition. Vols. I &amp; II. John Wiley &amp; Sons, New York, New York. 1181 pp.
  9. Hebda, A.J. 2011. List of mammals of Nova Scotia (including synonyms used in the literature relating to Nova Scotia) (revision 2) 24 July 2011. Nova Scotia Museum Collections Unit, Halifax, Nova Scotia. 24 pp. Online. Available: https://naturalhistory.novascotia.ca/sites/default/files/inline/images/names_and_synonyms_ver3.pdf
  10. IUCN (World Conservation Union). 1991. Dolphins, Porpoises and Whales of the World: the IUCN Red Data Book. M. Klinowska (compiler). IUCN, Gland, Switzerland, and Cambridge, United Kingdom. viii + 429 pp.
  11. Jones, J. K., Jr., R. S. Hoffman, D. W. Rice, C. Jones, R. J. Baker, and M. D. Engstrom. 1992a. Revised checklist of North American mammals north of Mexico, 1991. Occasional Papers, The Museum, Texas Tech University, 146:1-23.
  12. Katona, S. K., V. Rough, and D. T. Richardson. 1983. A Field guide to the whales, porpoises, and seals of the gulf of Maine and eastern Canada. Cape Cod to Newfoundland. Charles Scribner's Sons, N.Y. 255 pp.
  13. Leatherwood, S., and R. R. Reeves. 1983. The Sierra Club handbook of whales and dolphins. Sierra Club Books, San Francisco. 302 pp.
  14. Leatherwood, S., et al. 1980. Distribution and movements of Risso's dolphin, <i>Grampus griseus</i>, in the eastern North Pacific. Fish. Bull. 77:951-963.
  15. Pacheco, V., H. de Macedo, E. Vivar, C. Ascorra, R. Arana-Cardó, and S. Solari. 1995. Lista anotada de los mamíferos peruanos. Conservation International, Washington, DC.
  16. Rice, D. W. 1998. Marine mammals of the world: systematics and distribution. Society for Marine Mammalogy, Special Publication Number 4. ix + 231 pp.
  17. Tirira, D. 1999. Mamíferos del Ecuador. Museo de Zoología, Pontificia Universidad Católica del Ecuador, Quito.
  18. Wilson, D. E., and D. M. Reeder (editors). 1993. Mammal species of the world: a taxonomic and geographic reference. Second edition. Smithsonian Institution Press, Washington, DC. xviii + 1206 pp. Available online at: http://www.nmnh.si.edu/msw/.