View source for Biology:Fraser's dolphin

{{Short description|Species of mammal}}
{{Speciesbox
| name = Fraser's dolphin
| status = LC
| status_system = IUCN3.1
| status2 = CITES_A2 
| status2_system = CITES 
| status2_ref = <ref>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref>
| image = Fraser s group.jpg.jpeg
| image2 = Fraser's dolphin size.svg
| image2_caption = Size compared to an average human
| genus = Lagenodelphis
| parent_authority = Fraser, 1956
| species = hosei
| authority = Fraser, 1956<ref name="Fraser1956">''Lagenodelphis hosei'' Fraser, F.C. 1956. A new Sarawak dolphin. Sarawak Museum Journal 7(8, ns): 478-503 [478].</ref>
| display_parents = 2
| range_map = Cetacea range map Fraser'sDolphin.png
| range_map_caption = Fraser's dolphin range
|status_ref=<ref name="iucn status 19 November 2021">{{cite iucn |author=Kiszka, J. |author2=Braulik, G. |date=2018 |title=''Lagenodelphis hosei'' |volume=2018 |page=e.T11140A50360282 |doi=10.2305/IUCN.UK.2018-2.RLTS.T11140A50360282.en |access-date=19 November 2021}}</ref>
}}
'''Fraser's dolphin''' or the '''Sarawak dolphin''' ('''''Lagenodelphis hosei''''') is a cetacean in the family [[Biology:Delphinidae|Delphinidae]] found in deep waters in the [[Earth:Pacific Ocean|Pacific Ocean]] and to a lesser extent in the [[Earth:Indian Ocean|Indian]] and [[Earth:Atlantic Ocean|Atlantic Ocean]]s.

==Taxonomy==
''Lagenodelphis hosei'' is species of the delphinid family, distinguished from other dolphins as a monotypic genus, '''''Lagenodelphis'''''.<ref>{{cite journal |last1=Hershkovitz |first1=P. |year=1966 |title=Catalog of living whales |journal=Bulletin of the United States National Museum |issue=246 |pages=viii 1-259 [60] |doi=10.5479/si.03629236.246}}</ref>

In 1895, Charles E. Hose found a skull on a beach in Sarawak, Borneo. He donated it to the British Museum. The skull remained unstudied until 1956 when Francis Fraser<ref name="Fraser1956" /><ref>{{Cite journal | last1 = Marshall | first1 = N. B. | doi = 10.1098/rsbm.1979.0010 | title = Francis Charles Fraser. 16 June 1903-21 October 1978 | journal = Biographical Memoirs of Fellows of the Royal Society | volume = 25 | pages = 287–317| year = 1979 | s2cid = 71184662 }}</ref> examined it and concluded that it was similar to species in both the genera ''[[Biology:Lagenorhynchus|Lagenorhynchus]]'' and ''[[Biology:Common dolphin|Delphinus]]'' but not the same as either. A new genus was created by simply merging these two names together. The specific name is given in Hose's honour.

It wasn't until 1971 that the whole body of a Fraser's dolphin, as it was by then becoming known, was discovered. At that time washed-up specimens were found on Cocos Island in the eastern Pacific, in South Australia and in {{wipe|South Africa}}.

== Description ==
Fraser's dolphins are about {{Convert|1|m|abbr=on}} long and {{Convert|20|kg|abbr=on}} weight at birth, growing to {{Convert|2.75|m|abbr=on}} and {{Convert|200|kg|abbr=on}} by adulthood. They have a stocky build, a small fin in relation to the size of the body, as well as conspicuously small flippers. 

The dorsal fin and beak are also shorter than other species of dolphin. The upper side is a gray-blue to gray-brown. A dirty cream-colored line runs along the flanks from the beak, above the eye, to the anus. There is a dark stripe under this line. The belly and throat are usually white, sometimes tinged pink. The lack of a prominent beak is a distinguishing characteristic of this dolphin. From a distance, however, it may be confused with the [[Biology:Striped dolphin|striped dolphin]], which has a similar coloration and is found in the same regions.

Fraser's dolphins swim quickly in large, tightly-packed groups, numbering anywhere from 100 to 1,000 in number. Often porpoising, the groups chop up the water tremendously. The sight of seeing a large group fleeing from a fishing vessel has been reported as "very dramatic".

It is also unique in having the smallest genitalia of any open sea dolphin.

The species feeds on [[Biology:Pelagic fish|pelagic fish]], [[Biology:Squid|squid]] and shrimp found some distance below the surface of the water ({{Convert|200|m|ft|abbr=on|disp=x|/}} to {{Convert|500|m|ft|abbr=on|disp=x|/}}). Virtually no sunlight penetrates this depth, so feeding is carried out using [[Philosophy:Animal echolocation|echolocation]] alone.

== Population and distribution ==
{{unsourced section|date=March 2021}}
[[File:Bluewater Cruising.jpg|thumb|Dolphin in waters in Papua New Guinea]]
Though only accounted for relatively recently, the number of reported sightings has become substantial&nbsp;— indicating that the species may not be as rare as thought as recently as the 1980s. However the species is still not nearly as well understood as its more coastal cousins. No global population estimates exist.

The dolphin is normally sighted in deep tropical waters; between 30°S and 20°N. The Eastern Pacific is the most reliable site for viewings. Groups of stranded dolphins have been found as far afield as {{wipe|France}} and Uruguay. However these are regarded as anomalous and possibly due to unusual [[Physics:Oceanography|oceanographic]] conditions, such as [[Earth:El Niño|El Niño]].

The species is also relatively common in the Gulf of Mexico but less so in the rest of the Atlantic Ocean.

The {{wipe|Philippines}} is particularly known area for dolphin sightings, and is home to one of the larger populations of the Fraser's dolphin in the world.

== Conservation ==
The Southeast Asian populations of Fraser's dolphins are listed on Appendix II <ref name="Appendices">"[http://www.cms.int/documents/appendix/Appendices_COP9_E.pdf Appendix II] {{webarchive |url=https://web.archive.org/web/20110611112003/http://www.cms.int/documents/appendix/Appendices_COP9_E.pdf |date=11 June 2011 }}" of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.</ref> of the Convention on the Conservation of Migratory Species of Wild Animals (CMS), since they have an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.<ref>{{Cite web |url=http://www.cms.int/reports/small_cetaceans/data/L_hosei/L_hosei.htm |title=Convention on Migratory Species page on the Fraser's dolphin |access-date=31 August 2011 |archive-url=https://web.archive.org/web/20121015003633/http://www.cms.int/reports/small_cetaceans/data/L_hosei/L_hosei.htm |archive-date=15 October 2012 |url-status=dead }}</ref>

In addition, Fraser's dolphin is covered by Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region ([[Biology:Pacific Islands Cetaceans Memorandum of Understanding|Pacific Cetaceans MoU]])<ref>[http://www.pacificcetaceans.org/ Pacific Cetaceans MoU]</ref> and the Memorandum of Understanding Concerning the Conservation of the Manatee and Small Cetaceans of Western Africa and Macaronesia ([[Biology:West African Aquatic Mammals Memorandum of Understanding|Western African Aquatic Mammals MoU]]).<ref>[http://www.cms.int/species/waam/index.htm Western African Aquatic Mammals MoU]</ref>

==See also==
*List of marine mammal species
*List of cetaceans
*[[Biology:Marine biology|Marine biology]]

==Footnotes==
{{Notelist}}

==References==
{{Reflist}}

==Further reading==
* {{Cite iucn | author = Hammond, P.S. | author2 = Bearzi, G. | author3 = Bjørge, A. | author4 = Forney, K. | author5 = Karczmarski, L. | author6 = Kasuya, T. | author7 = Perrin, W.F. | author8 = Scott, M.D. | author9 = Wang, J.Y. | author10 = Wells, R.S. | display-authors = etal | title = ''Lagenodelphis hosei'' | volume = 2012 | page = e.T11140A17807828 | date = 2012 | doi = 10.2305/IUCN.UK.2012.RLTS.T11140A17807828.en }} Database entry includes justification for why this species is listed as data deficient
*''Whales Dolphins and Porpoises'', Mark Carwardine, Dorling Kindersley Handbooks, {{ISBN|0-7513-2781-6}}
*''National Audubon Society Guide to Marine Mammals of the World'', Reeves, Stewart, Clapham and Powell, {{ISBN|0-375-41141-0}}
*''Malaysian Naturalist'', Vol 59/3 - 2006, page 5.

==External links==
*[http://cetus.ucsd.edu/voicesinthesea_org/species/dolphins/frasers.html Voices in the Sea - Sounds of the Fraser's dolphin] {{Webarchive|url=https://web.archive.org/web/20140709234241/http://cetus.ucsd.edu/voicesinthesea_org/species/dolphins/frasers.html |date=9 July 2014 }}

{{Cetacea|O.}}
{{Taxonbar|from=Q751965}}

[[Category:Oceanic dolphins|Fraser's dolphin]]
[[Category:Cosmopolitan mammals]]

{{Sourceattribution|Fraser's dolphin}}