Taxonomy
Balaenoptera acutorostrata | Minke Whale
Distribution
Status
Conservation status
| HABITATS DIRECTIVE ARTICLE 17 REPORTING |
| Range | Favourable |
| Population | Favourable |
| Habitat | Favourable |
| Future Prospects | Favourable |
| Overall Assessment of Conservation Status | Favourable |
| Overall Trend in Conservation Status | N / A |
IUCN Conservation Status |
| Ireland | Not Evaluated* |
| Europe (1) | Least Concern |
| Global (2) | Least Concern |
* 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*
- Convention on Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix I
- International Convention for the Regulation of Whaling 1946 (as amended)
- Council Regulation (EC) No. 812/2004
- Wildlife Act (1976)
- Wildlife (Amendment) Act (2000)
- Whale Fisheries Act 1937
Native status
The Minke Whale is seen in Irish waters for most of the year- most records are made from late Spring to Autumn. Around calving time (December-February), the species is largely un-recorded in Irish waters. It is possible that the species moves to lower latitudes to give birth.
Source: Irish Whale and Dolphin Group.
The 2008 IUCN Global Red List for this species lists Ireland as one of
the countries where it is native, however it probably better described
as a migrant in an Irish context.
Sources: Reilly, S.B. et al 2008.; de Klem, 1994
Species Biology
Identification
- Max. adult body length: 10m
- Max. adult weight: 15 tonnes
- Average adult body length: 7m
- Average adult weight: 10 tonnes
- Average length of calf at birth: 2.6m
- Average weight of calf at birth: 350kg
- Blow: The Minke's blow is a short quick 3m blow. It is generally not visible, unless seen at close range or in calm conditions, when it can be heard.
- Head: The head is narrow and sharply pointed, with a single ridge, which runs down the centre of the triangular shaped rostrum, beginning in front of the blowholes. This ridge resembles that of the fin whale, except that it is much sharper (hence the name Sharp-headed Finner). The rostrum is flattened. The baleen is short and is sometimes visible when a whale is feeding.
- Dorsal Fin: The dorsal fin is tall and falcate and is highly variable. It is positioned quite far forward, slightly less than 2/3 of the way back from the tip of the rostrum (as in the Sei Whale).
- Pectoral Fins: Small and pointed (about 1/8 the total body length) and have a conspicuous white diagonal band (variable) on the upper surface.
- Colouration: Minke Whales are black, brown, or dark grey on their backs and lighter on the belly and underside of the flippers. The most conspicuous feature of these animals in the Northern Hemisphere is a diagonal band of white on the upper surface of each flipper. The extent and orientation of the white band on the flipper varies individually. In the Southern Hemisphere, the presence and extent of the white flipper stripe is variable, and may not be present. Minke Whales sometimes have a pale chevron on the back (like Fin Whales), behind the head and two regions of light grey on each side - one just above and behind the flipper, and another just in front of and below the dorsal fin. These may be conspicuous in some individuals and not in others. The tail flukes may be pale grey, bluish-grey or white on the underside, usually with a dark margin. The baleen plates are white, grey or cream in colour. There are 50-70 thin ventral pleats on the throat and belly, the longest of which end slightly anterior to the navel.
- Markings: Identification of individual Minke Whales is possible using a combination of naturally occurring features (shape of dorsal fin, scars, pigmentation) which vary between individuals. This technique has facilitated photo-identification studies of Minke Whales in some areas.
- The dive sequence of the Minke Whale is quite distinctive and aids identification from other easily confused species such as Sei, Fin or Northern Bottlenose Whales. The sharply pointed snout, which breaks the water surface first and the sight of both blow and dorsal fin simultaneously distinguishes the Minke Whale from all other rorqual whales with the exception of the Sei Whale. The back and tail stock arch more strongly than the Sei Whale as the Minke prepares for a long dive and the tail stock is strongly arched, but the flukes do not appear above the surface.
Source: Irish Whale and Dolphin Group.
Habitat
This species has a global distribution in temperate to sub-arctic waters, generally over continental shelf and can be found very close to shore, occasionally even recorded in estuaries, bays &c.
Source: Harris S., Yalden D.W. 2008.
Habitat;
- Marine water body (M)
Sources: Harris S.,Yalden D.W., 2008; Fossitt, J.A., 2001.
Reproduction
- Max. life expectancy: 40-50 years.
- Average life expectancy: 45 years.
- Mating Occurs: January - May.
- Gestation: Approximately 10 months.
- Calving: December - January.
Minke Whales produce a calf every two years, and this calf is weaned after six months – the earliest known weaning period for any baleen species.
Source: Irish Whale and Dolphin Group.
Threats faced
| THREAT | ARTICLE 17 THREAT CODE | RANKING |
| Seismic exploration, explosions | H06.05 | Medium |
| Fishing and harvesting aquatic resources* | F02 | Medium |
| 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 EU territory | XE | Low |
*This would include the threat to this species cuased by 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.
The 2008 Global IUCN Red List assessment for the species includes as a threat;- Habitat shift as a result of Climate Change.
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.
Source: NPWS 2013.
Apart from an acknowledgement of the existence of legislative protection, there are no suggested Conservation Actions in the 2007 European Regional IUCN Red List assessment or the 2008 Global IUCN Red List assessment for this species.
Sources: IUCN SSC Cetacean Specialist Group 2007; Reilly, S.B et al 2008.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)
Cosmopolitan, although not known fromn the Indian Ocean.
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
Minke whales can be seen off most headlands on the west and south west coastline of Ireland, less so in the Irish Sea. There appears to be a seasonal inshore migration of Minke whales off Loop Head during September and October but can be seen throughout the year. Minke whales have been stranded on every coastline in Ireland with the highest incidence of strandings on the south and south west coastlines.
In the years 1999-2001 they were, perhaps surprisingly, the 2nd most frequently observed baleen whale, after the fin whale. They are the 5th most frequently stranded cetacean in Ireland.
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 Minke 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
de Klem, Cyrille, 1994. ‘The Problem of Migratory Species in International Law’, in Helge Ole Bergesen and Georg Parmann (eds.), Green Globe Yearbook ofInternational Co-operation on Environment and Development 1994(Oxford: Oxford University Press), 67–77.
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. Balaenoptera acutorostrata. 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
Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N. 2008. Balaenoptera acutorostrata. 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.