







| Kingdom | Phylum | Class | Order | Family |
|---|---|---|---|---|
| ANIMALIA | CHORDATA | MAMMALIA | CETARTIODACTYLA | BALAENIDAE |
| Scientific Name: | Balaena mysticetus | |||||||||
| Species Authority: | Linnaeus, 1758 | |||||||||
| Infra-specific Taxa Assessed: |
See Balaena mysticetus (Bering-Chukchi-Beaufort Sea subpopulation)
See Balaena mysticetus (Okhotsk Sea subpopulation)
See Balaena mysticetus (Svalbard-Barents Sea (Spitsbergen) subpopulation)
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Common Name/s:
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| Taxonomic Notes: | The taxonomy is not in doubt. There are five traditionally recognized geographical International Whaling Commission (IWC) stocks (see below) of which two (Okhotsk Sea and Svalbard-Barents Sea (Spitsbergen)) have separate Red List assessments as subpopulations. Concerning common names, the species was once commonly known in the North Atlantic and adjacent Arctic as the Greenland Right Whale. However, the common name Bowhead Whale is now generally used for the species. | |||||||||
| Red List Category & Criteria: | Least Concern ver 3.1 | |||||||||||||||
| Year Assessed: | 2008 | |||||||||||||||
| Assessor/s | 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. | |||||||||||||||
| Evaluator/s: | Taylor, B.L. & Notarbartolo di Sciara, G. (Cetacean Red List Authority) | |||||||||||||||
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Justification: The global population appears to be increasing, due primarily to the increase in the large Bering-Chukchi-Beaufort subpopulation, even though the trends in the remaining populations are unclear. The BCB subpopulation size is well above the Vulnerable threshold for a non-declining population, and current assessments suggest that this stock has recovered to close to its pre-whaling level. The estimate of over 7,000 animals for part of the range of the Hudson Bay-Foxe Basin and Baffin Bay-Davis Strait stocks combined is still provisional, but it is unlikely that the final numbers would be so low that these subpopulations (or the single combined subpopulation) would qualify for a threatened category. Bowhead whale numbers in eastern Canada and West Greenland are probably still below their pre-whaling levels, although the main reductions occurred before the three-generation time window that would trigger the population reduction (A) criterion. For all these reasons, the species is listed as Least Concern. |
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| History: |
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| Population: |
Current Population sizes The range-wide abundance is not known with precision but numbers over 10,000 individuals, with 10,500 (8,200–13,500) (in 2001) in the Bering- Chukchi-Beaufort Seas (Zeh and Punt 2005), and provisional estimates of 3,633 (1,382-9,550) (Koski et al. 2006) and 7,300 (3,100–16,900) for parts of the range of the Hudson Bay-Foxe Basin and Baffin Bay-Davis Strait stocks (Cosens et al. 2006). There are no reliable abundance estimates for the small Okhotsk Sea and Svalbard-Barents Sea (Spitsbergen) stocks (see separate listings). Population trends The Bering-Chukchi-Beaufort (BCB) subpopulation has been monitored for more than 30 years and has been increasing over this period at an estimated rate of 3.4% (1.7–5%) per year in the presence of subsistence hunting (Zeh and Punt 2005). No quantitative estimates of trends in the other bowhead populations are available, but Inuit hunters and elders report that they are observing more bowheads in the eastern Canadian Arctic and West Greenland than they did in the 1960s–1970s, and that the geographic distribution of the whales has expanded in recent years (Koski et al. 2006). No estimates of subpopulation trend are available for the Svalbard-Barents Sea (Spitsbergen) and Okhotsk Sea stocks (see separate listing). Pre-whaling population sizes All bowhead subpopulations were severely depleted by commercial whaling, which had begun in the northeastern Atlantic by 1611 (Ross 1993). Basque whalers took bowheads in the northwest Atlantic (Labrador in Canada) in the 16th century, but ambiguities over the species identity of whales taken in early commercial whaling make pre-1600 catch records difficult to interpret. Minimum pre-whaling subpopulation sizes are estimated to have been 24,000 for the Svalbard-Barents Sea (Spitsbergen) stock, 12,000 for the Hudson Bay-Foxe Basin and Baffin Bay-Davis Strait subpopulation(s), and 3,000 for the Okhotsk Sea stock (Woodby and Botkin 1993). Brandon and Wade (2004) estimate the initial abundance of the BCB subpopulation at 10–20,000. The BCB stock may be approaching its pre-whaling levels (IWC 2005). The Svalbard-Barents Sea (Spitsbergen) and Okhotsk Sea stocks are each at a small fraction of their pre-whaling levels (see separate listings), while the status of the Hudson Bay-Foxe Basin and Baffin Bay-Davis Strait animals relative to pre-whaling levels is unclear. Demographic parameters A high longevity (>100 years) is suggested by biochemical methods and the finding of old-fashioned stone harpoon heads in hunter-killed animals (George et al. 1999). If this high longevity is confirmed, it would be among the longest known for a mammal. For the BCB subpopulation, an estimated 44% (SE 1%) of the total population consists of reproductively mature animals, given that the age at maturity is at least 20 years (Koksi et al. 2004). The calving interval is 3–4 years (Rugh et al. 1992). No specific data are available for other subpopulations. Taylor et al. (2007) estimate the generation time for bowhead whales to be around 52 years. |
| Population Trend: |
Increasing
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| Habitat and Ecology: |
The seasonal distribution is strongly influenced by pack ice (Moore and Reeves 1993). During the winter bowhead whales occur in areas near the ice edge, in polynyas, and in areas of unconsolidated pack ice. During the spring these whales use leads and cracks in the ice to penetrate areas that were inaccessible during the winter due to heavy ice coverage. During the summer and autumn they concentrate in areas where zooplankton production is high or where large-scale biophysical processes create local concentrations of calanoid copepods (Finley 1990, Finley et al. 1998). Small to medium-sized crustaceans, especially krill and copepods, form the bulk of the bowhead's diet (Lowry et al. 2004). They also feed on mysids and gammarid amphipods, and the diet includes at least 60 species. Bowheads skim feed at the surface and feed in the water column. It has recently been suggested that they also feed near the bottom, but probably do not directly ingest sediments as gray whales routinely do. |
| Systems: | Marine |
| Major Threat(s): |
Heavy commercial hunting, beginning in the 1500s, depleted all populations of bowheads. The Bering-Chukchi-Beaufort Seas stock has recovered substantially since the end of commercial whaling in the early 20th century, while recent provisional estimates of the Hudson Bay-Foxe Basin and Baffin Bay-Davis Strait stocks also suggest significant recovery. There is no reliable evidence of recovery of the Svalbard-Barents Sea (Spitsbergen) and Okhotsk Sea stocks. Limited aboriginal subsistence whaling on the BCB stock (by native peoples of Alaska, and the Russian Federation (Chukotka) is permitted by the IWC on the basis of advice from its Scientific Committee (most recently under its new aboriginal subsistence whaling management procedure). These takes have not impeded the recovery of the stock. Very small takes by aboriginal hunters are allowed in Canadian waters. So far these have been too few to impede recovery of the stocks, but there will be pressure to increase take levels given the recent, higher population estimates in the eastern Canadian Arctic. There has been concern since the 1970s that disturbance from oil and gas exploration and extraction activities in the Arctic region might affect bowhead whales. There is also evidence of incidental mortality and serious injury caused by entanglement in fishing gear and ship strikes (Philo et al. 1992, 1993; Finley 2000). Environmental threats, such as pollution (Bratton et al. 1993) and disturbance from tourist traffic (Finley 2000), may affect bowhead whales but the impacts have not yet been well characterized or quantified. During this century, a profound reduction in the extent of sea ice in the Arctic is expected, and possibly a complete disappearance in summer, as mean Arctic temperatures rise faster than the global average (Anonymous 2005). The implications of this for bowhead whales are unclear but warrant monitoring. |
| Conservation Actions: | The International Whaling Commission has protected bowhead whales from commercial whaling since its inception in 1946; all range states except Canada are members of the IWC. Limited aboriginal subsistence whaling is allowed by the IWC on bowhead whales from the BCB stock on the basis of scientific advice (see above). Aboriginal hunting in Canada is co-managed by the national government and regional bodies created under land-claim agreements. This species has been included in CITES Appendix I since 1975; Canada had a reservation against this listing until 1978. The species is listed in CMS Appendix I. |
| Citation: | 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. Balaena mysticetus. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.2. <www.iucnredlist.org>. Downloaded on 21 November 2009. |
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