Tasmacetus shepherdi (Oliver, 1937)

English: Shepherd's beaked whale; Tasman beaked whale
German: Shepherdwal
Spanish: Ballena picuda de Shepherd
French: Tasmacète

Family: Ziphiidae


Tasmacetus shepherdi © Würtz-Artescienza (see "links")


1. Description

Tasmacetus shepherdi is thought to be a rare animal, known from only 29 strandings and 6 sightings in the Southern Hemisphere (Mead, 2009), however limited survey effort in deep offshore waters may partly explain its apparent scarcity. Adults are between 6 and 7m long and have a full set of functional teeth, as opposed to all other beaked whale species. Colouring is distinctive for ziphiids (Jefferson et al 2008) dark grey dorsally with a white ventral field extending towards the back on both anterior and posterior sides of the flippers (Mead, 2002) and on the side of the face just below gape and eye (Jefferson et al., 2008).back to the top of the page


2. Distribution

Tasman's beaked whale is probably circumglobal in temperate waters of the Southern Hemisphere, but stranded specimens have been collected only in New Zealand, Australia, the Juan Fernandez Islands and on Tristan da Cunha (Rice, 1998; Mead, 2009). It is associated with cooler waters from 33°S to 53°50'S (Van Waerebeek et al., 2004).

Distribution of Tasmacetus shepherdi: cold temperate waters of the Southern
Hemisphere, predominantly New Zealand (mod. from Mead, 2009,
Taylor et al. 2008; © IUCN; enlarge map).

Mead (2009) lists a total of six published sightings from New Zealand, the Seychelles (Islands), the South Sandwich Islands, Tristan da Cunha and Tasmania.back to the top of the page


3. Population size

Nothing is known about the relative abundance of this species or its population composition. It is suspected, based on the lack of identified sightings, that all ziphiids except Berardius and Hyperoodon, have relatively small populations. This could also be due to their naturally cryptic habits (Mead, 1989). However, it is possible that the species may be somewhat more widespread than the records suggest, since it was not likely to be accurately identified at sea until its recent re-description (Pitman et al. 2006).back to the top of the page


4. Biology and Behaviour

Habitat: Mead (2009) suggests that similarly to the other beaked whales, Shepherd's beaked whale presumably feeds offshore in deep waters.

Schooling: Pitman et al. (2006) report of aerial photographs (Tristan da Cunha Islands, Gough island, South Atlantic Ocean) of various groups ranging from 4 - 5 Shepherd's whales.

Food: Mead and Payne (1975) examined a stranded adult female in Argentina and found traces of bottom fish, squid and a small crab. Pitman et al. (2006) reports that a stranded animal from Tristan da Cunha had only cephalopod remains in its stomach: "single buccal masses from Todarodes filippovae and Teuthowenia pellucida, single beaks from Ancistrocheirus lesueuri and Histioteuthis, and one unidentified cephalopod beak; all the eye lenses present were from cephalopods, not fish".back to the top of the page


5. Migration

Six of the strandings have occurred in the southern summer (November-March) and one has occurred in the winter (August). This is too small a sample on which to base conclusions on seasonal distribution (Mead, 1989).back to the top of the page


6. Threats

There are no records of human exploitation (Jefferson et al. 1993, Mead, 2009). Marine pollution, however, might pose a problem, as one stranded calf was found to have plastic debris in its stomach (Mead, 2009).back to the top of the page


7. Remarks

Range states (Taylor et al. 2008) :
Argentina; Australia; Chile (Juan Fernández Is.); New Zealand (Stewart and Chatham Is., North Is., South Is.); Saint Helena (Tristan da Cunha); South Africa.

Tasman's beaked whale is listed by the IUCN as "Data Deficient" and not listed by CMS. Listed on Appendix II of CITES.

T. shepherdi also occurs in southern South America, therefore the recommendations iterated by the scientific committee of CMS for small cetaceans in that area (Hucke-Gaete, 2000 in Appendix 1) also apply.back to the top of the page


8. Sources

· Hucke-Gaete R (2000) Review of the conservation status of small cetaceans in southern South America. UNEP/CMS Secretariat, Bonn, Germany, 24 pp.
· Jefferson TA, Webber MA Pitman RL (2008) Marine mammals of the world. Elsevier, Amsterdam, 573 pp.
· Jefferson TA, Leatherwood S, Webber MA (1993) FAO Species identification guide. Marine mammals of the world. UNEP/FAO, Rome, 320 pp.
· Mead JG (2009) Shepherd's beaked whale - Tasmacetus shepherdi. In: Encyclopedia of marine mammals (Perrin WF, Würsig B, Thewissen JGM, eds.) Academic Press, San Diego, pp. 1011-1014.
· Mead JG (2002) Shepherd's beaked whale - Tasmacetus shepherdi. In: Encyclopedia of marine mammals (Perrin WF, Würsig B, Thewissen JGM, eds.) Academic Press, San Diego, pp. 1078-1081.
· Mead JG (1989) Shepherd's Beaked Whale - Tasmacetus shepherdi Olivier, 1937. In: Handbook of Marine Mammals (Ridgway SH, Harrison SR, eds.) Vol. 4: River Dolphins and the Larger Toothed Whales. Academic Press, London, pp. 309-320.
· Mead JG, Payne RS (1975) A specimen of the Tasman beaked whale Tasmacetus shepherdi from Argentina J Mammal 56: 213-218
· Pitman RL, van Helden AL, Best PB, Pym A (2006) Shepherd's beaked whale (Tasmacetus shepherdi): information on appearance and biology based on strandings and at-sea observations. Mar Mamm Sci 22: 744-755
· Rice DW (1998) Marine mammals of the world: systematics and distribution. Society for Marine Mamma-logy, Special Publication Number 4 (Wartzok D, ed.), Lawrence, KS. USA
· Taylor BL, Baird R, Barlow J, Dawson SM, Ford J, Mead JG, Notarbartolo di Sciara G, Wade P, Pitman RL (2008). Tasmacetus shepherdi. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1. <www.iucnredlist.org>.

© Boris Culik (2010) Odontocetes. The toothed whales: "Tasmacetus shepherdi". UNEP/CMS Secretariat, Bonn, Germany. http://www.cms.int/reports/small_cetaceans/index.htm
© Illustrations by Maurizio Würtz, Artescienza. © Maps by IUCN.

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