Hector's Beaked Whale

Taxobox
name = Hector's Beaked Whale
status = DD
status_system = iucn2.3

---

image2_caption = Size comparison against an average human
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Cetacea
subordo = Odontoceti
familia = Ziphidae
genus = "Mesoplodon"
species = "M. hectori"
binomial = "Mesoplodon hectori"
binomial_authority = Gray, 1871
range_

range_map_caption = Hector's Beaked Whale range

Hector's Beaked Whale, "Mesoplodon hectori", is a small Mesoplodont living in the Southern Hemisphere. This whale is named after Sir James Hector, a founder of the colonial museum in Wellington, New Zealand. Some specimens that have washed up and been sighted in California that were once thought to belong to this species have subsequently been shown through analysis of mtDNA and detailed morhological examination to be a new species,Perrin's Beaked Whale (Dalebout "et al." 2002). As of 2007, they have yet to be seen alive in the wild.

Note that some data supposedly referring to this species, especially juveniles and males, turned out to be based on the misidentified specimens of Perrin's Beaked Whale - especially since the adult male of Hector's Beaked Whale was only more recently described. See Perrin's Beaked Whale for specimen data. Dalebout "et al." (2002) specifically list Mead (1981), Mead (1984), Mead & Baker (1987), Mead (1989), Baker (1990), Jefferson "et al." (1993), Mead (1993), Carwardine (1995), Reeves & Leatherwood (1994), Henshaw "et al". (1997) and Messenger & McQuire (1998) as erroneously attributing data from the new species to Hector's Beaked Whale.

Physical description

Reaching a maximum length of about 4.2 meters (1.9 m when born), and with an estimated weight of about 1 tonne (1.032 tons), Hector's is one the smallest of the beaked whales. It is known from only a few stranded animals. Hector's Beaked Whales are dark greyish-brown dorsally, paler ventrally and may have white or pale lower jaws. The melon, which is not very prominent, slopes quite steeply to the short beak. Adult males have a pair of flattened, triangular teeth near the tip of the lower jaw. As with most other beaked whales, the teeth do not erupt in females. The dorsal fin is triangular to slightly hooked, small, and rounded at the tip. The leading edge of the dorsal fin joins the body at a sharp angle.

Diet

Nothing is known about the diet of this species, although it is assumed to feed on deepwater squid and fish. Because they lack functional teeth, they presumably capture most of their prey by suction.

Behavior

With only two probable sightings, there is little information on the behavior of this whale. This species may be unusual for a Mesoplodon because, in both sightings, one of the animals seemed inquisitive and actually approached the boat. Body scarring suggests there may be extensive fighting between males, which is common in beaked whales.

Breeding

Nothing is known about breeding in this species. Sightings are rare due to their deep-ocean distribution, elusive behaviour and possible low numbers.

Population and Distribution

Hector's Beaked Whale has a circumpolar distribution in cool temperate Southern Hemisphere waters between approximately 35° and 55°S. Most records are from New Zealand, but there are also reports from Falkland Sound, Falkland Islands, Lottering River, South Africa, Adventure Bay, Tasmania, and Tierra del Fuego, in southern South America.

Conservation

This species has never been hunted at all, and has not entangled itself in fishing gear. Most sightings of the whale have been stranded specimens on beaches, particularly in New Zealand.

References

* (1990): "Whales and dolphins of New Zealand and Australia: An identification guide". Victoria University Press, Wellington.
* (1995): "Whales, dolphins and porpoises". HarperCollins, London.
*|year=1996|id=13248|title=Mesoplodon hectori|downloaded=12 May 2006
* (2002): A New Species of Beaked Whale, "Mesoplodon perrini" sp. n. (Cetacea: Ziphiidae), Discovered Through Phylogenic Analysis of Mitochondrial DNA Sequences. "Marine Mammal Science" 18(3): 577-608. doi|10.1111/j.1748-7692.2002.tb01061.x [http://whitelab.biology.dal.ca/md/Dalebout_2003_Mperrini.pdf PDF fulltext]
* (1997): Identification of beaked whales (family Ziphiidae) using mtDNA sequences. "Marine Mammal Science" 13(3): 487-495. doi|10.1111/j.1748-7692.1997.tb00656.x (HTML abstract)
* (1993): "FAO species identification guide: Marine mammals of the world." United States Environment Programme & Food and Agriculture Organization of the United Nations (FAO), Rome. [ftp://ftp.fao.org/docrep/fao/009/t0725e/t0725e.zip PDF fulltexr]
* (1981): First records of "Mesoplodon hectori" (Ziphiidae) from the northern hemisphere and a description of the adult male. "Journal of Mammalogy" 62(2): 430-432. doi|10.2307/1380733 (First page image)
* (1984): Survey of reproductive data for the beaked whales (Ziphiidae). "Report of the International Whaling Commission Special Issue" 6: 91-96.
* (1989): Beaked whales of the genus "Mesoplodon". "In:" aut|Ridgway, S.H. & Harrison, R. (eds.): Handbook of marine mammals Vol.4: 349-430. Academic Press, London.
* (1993): The systematic importance of stomach anatomy in beaked whales. "IBI Reports" 4: 75-86.
* (1987): Notes on the rare beaked whale, "Mesoplodon hectori" (Gray). "Journal of the Royal Society of New Zealand" 17: 303-312.
* (1998): Morphology, molecules and the phylogenetics of cetaceans. "Systematic Biology" 47(1): 90-124. doi|10.1080/106351598261058 (HTML abstract)
* (2002): "Encyclopedia of Marine Mammals". Academic Press. ISBN 0-12-551340-2
* (1994): "Dolphins, porpoises and whales: 1994-98 Action plan for the conservation of cetaceans". IUCN, Gland, Switzerland. ISBN 2-8317-0189-9
* (2002): "Sea Mammals of the World". A & C Black, London. ISBN 0-7136-6334-0

External links

* [http://www.austmus.gov.au/factsheets/hectors_beaked.htm Hector's Beaked Whale Fact Sheet]
* [http://www.sci.tamucc.edu/tmmsn/29Species/MoreSpec/hectorsbeakedwhale.html Cetaceans of the World]
* [http://www.cms.int/reports/small_cetaceans/data/m_hectori/m_hectori.htm CMS]
* [http://www.wdcs.org Whale & Dolphin Conservation Society (WDCS)]