Taxonomy
Mesoplodon bidens | Sowerby's Beaked Whale
Distribution
Status
Conservation status
| HABITATS DIRECTIVE ARTICLE 17 REPORTING |
| Range | Favourable |
| Population | Unknown |
| Habitat | Favourable |
| Future Prospects | Unknown |
| Overall Assessment of Conservation Status | Unknown |
| Overall Trend in Conservation Status | N / A |
IUCN Conservation Status |
| Ireland | Not Evaluated* |
| Europe (1) | Data Deficient |
| Global (2) | Data Deficient |
* There is currently no Irish Red List for Marine Mammals.
Legal status
Protected by the following legal instruments:
- Habitats Directive (92/43/EEC) Annex IV
- Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention) Appendix II
- Agreement on the Conservation of Small Cetaceans in the Baltic, North East Atlantic, Irish and North Seas*
- Convention on Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix II
- Council Regulation (EC) No. 812/2004
- Wildlife Act (1976)
- Wildlife (Amendment) Act (2000)
- Whale Fisheries Act 1937
Native status
The 2008 IUCN Global Red List for this species lists Ireland as one of the countries where it is native.
Source: Taylor, B.L. et al 2008.
Sightings of live animals are rare, likely due to the species preference for deeper water. As there is insufficient information on seasonal distribution in Irish waters, for the purposes of this profile Ziphius cavirostris is considered as native.
Source: Irish Whale and Dolphin Group.
Species Biology
Identification
- Max. adult length: 6.7m
- Max. adult weight: 1,300kg
- Average adult length: 5m
- Average adult weight: 1,100kg
- Average lengthof calf at birth: 2.4m
- Average weight of calf at birth: 170kg
- Blow: Faint and inaudible, even at close range.
- Head: A definite bulge is present just in front of the blowhole. The beak is long and slim. The lower jaw slightly protrudes beyond the upper.
- Dorsal Fin: Small fin located two-thirds of way along the back.
- Colouration: Bluish to dark grey but younger animals tend to have lighter bellies. All individuals have white areas on the lower jaw.
- Markings: As they grow older they become progressively more scarred with rake marks and white, oval rings caused by parasites.
Habitat
Based on confirmed sightings at sea and evidence from bycatch Sowerby's Beaked Whale most likely inhabits deeper oceanic waters beyond the limits of continental shelf slopes. Distribution centred on temperate waters of the North Atlantic east, central and west.
Source: Harris S., Yalden D.W. 2008
Habitat;
- Open marine water (MW1)
Sources: Harris S., Yalden D.W. 2008.; Fossitt, J.A., 2001.
Reproduction
- Max. life expectancy: At least 35yrs.
- Average life expectancy: Unknown.
- Mating Occurs: Unknown.
- Calving: Winter.
- Gestation: Unknown.
Threats faced
| THREAT | ARTICLE 17 THREAT CODE | RANKING |
| Seismic exploration, explosions | H06.05 | Medium |
| Fishing and harvesting aquatic resources* | F02 | Low |
| Death or injury by collision | G05.11 | Low |
| Noise nuisance, noise pollution | H06.01 | Low |
| Changes in abiotic conditions | M01 | Low |
| Threats and pressures from outside the Member State | XO | Low |
*This would include the threat to this species of a reduction in prey availability as well as the threat of becoming by-catch / accidental catch and also entanglement in fishing gear.
These threats accord well with threats outlined in the 2007 European Regional IUCN Red List assessment for the species which did not identify any other threats that may be relevant in Irish waters.
Source: IUCN SSC Cetacean Specialist Group 2007.
Conservation actions
In the Article 17 Habitats Directive reporting for the period 2007-2012 no Conservation Measures in place or in the process of being implemented during the period were listed for this species.
In addition to an acknowledgement of the existence of legislative protection, suggested Conservation Actions in the 2007 European Regional IUCN Red List assessment for this species included;
- More co-ordinated research efforts by range states.
In a 2009 Cetacean Action Plan a total of 41 Actions were identified as part of the plan. The plan and the 2013 review of the plan are available from the NPWS website.
Source: DEHLG 2009.
Distribution
World distribution(GBIF)
Distribution centred on temperate waters of the North Atlantic east, central and west.
Source: Harris S., Yalden D.W. 2008
Accuracy of world distribution shown in the Global Biodiversity Information Facility (GBIF) map below will be constrained by, amongst other factors, data held but not shared by countries and organizations not participating in the GBIF.
Irish distribution
Apart from four sightings along the west and south coasts, little is known about Sowerby's beaked whale in Irish waters. It may be more common here than records suggest, though its main distribution in Irish waters lies in deep waters off the edge of the continental shelf. It has been recorded during recent surveys off the shelf edge. Animals may migrate southward in winter and closer to shore during summer months.
Source: Irish Whale and Dolphin Group.
Temporal change
Records submitted to Data Centre in 2024
The following map is interactive. If you would prefer to view it full screen then click here.
How can you help
The National Biodiversity Data Centre is trying to
improve our knowledge on the distribution of the Sowerby's Beaked Whale in
Ireland. Should you observe this species, please submit
sightings to add to the database. Detailed observations will assist us
gaining a better insight into where the species
is most abundant in Ireland and we might also be able to detect
regional variations. Please submit any sightings and photographs at:
http://records.biodiversityireland.ie/index.php
All
records submitted online can be viewed on Google Maps – once checked
and validated these will be added to the database and made available for
conservation and research.
Further information
For further information contact Dr. Liam Lysaght llysaght@biodiversityireland.ie
References
Publications
DEHLG (2009) Conservation Plan for Cetaceans in Irish waters.
Fossitt, J.A. (2001) A Guide to Habitats in Ireland. The Heritage Council
Harris S., Yalden D.W. (2008). Mammals of the British Isles :Handbook, 4th Edition. The Mammal Society.
Species account by IUCN SSC Cetacean Specialist Group; regional assessment by European Mammal Assessment team 2007. Mesoplodon bidens. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 15 October 2014.
NPWS (2013) The Status of EU Protected Habitats and Species in Ireland. Species Assessments Volume 3. Version 1.0. Unpublished Report, National Parks & Wildlife Services. Department of Arts, Heritage and the Gaeltacht, Dublin, Ireland.
NPWS (2013a) Delivery Schedule for Actions listed in the Conservation Plan for Cetaceans in Irish waters – June 2013
Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L. 2008. Mesoplodon bidens. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 15 October 2014.
Wall, D., Murray, C., O’Brien, J., Kavanagh, L., Wilson, C., Ryan, C., Glanville, B., Williams, D., Enlander, I., O’Connor, I., McGrath, D., Whooley, P. & Berrow, S. (2013). Atlas of the Distribution and Relative Abundance of Marine Mammals in Irish Offshore Waters: 2005 – 2011. Irish Whale and Dolphin Group, Kilrush, Co. Clare.