Thick-billed murre
Common Name: Thick-billed murre
Scientific Name: Uria lomvia
OSPAR Regions where it occurs: I
OSPAR Regions where under threat and/or in decline: I
Description: The thick-billed murre or Brünnich's guillemot (Uria lomvia) is a bird in the auk family (Alcidae). Since the extinction of the great auk in the mid-19th century, the murres are the largest living members of the Alcidae. The thick-billed murre and the closely related common guillemot (or common murre, U. aalge) are similarly sized, but the thick-billed still bests the other species in both average and maximum size. The thick-billed murre measures 40–48 cm (16–19 in) in total length, spans 64–81 cm (25–32 in) across the wings and weighs 736–1,481 g (26.0–52.2 oz).
What is the latest status?
The status assessment describes the latest changes in distribution, abundance and range of the feature, as well as any changes in the threats and pressures impacting the feature. The status assessments are updated regularly and inform OSPAR’s consideration of the effectiveness of the measures and actions that have been adopted and implemented by Contracting Parties.
Key Facts
Key message
Breeding populations of the Brünnich‘s guillemot (BRGU) in Svalbard, East Greenland and northern Norway are currently declining, with climate change and its indirect effects as the most likely pressures driving the negative trend. Further threats in some areas include hunting, disturbance by predators, as well as chemical and oil pollution. Populations in Iceland and Franz Josef Land have shown stable or increasing trends. For more information read our latest status assessment.
Distribution
Within the Northeast Atlantic, the species breeds in Norway (incl. Svalbard and Jan Mayen), Russia, Greenland and Iceland (OSPAR Region I, Bakken and Pokrovskaya, 2000).Most of the population breeds in the Arctic at high latitudes (>60 °N). For more information read our latest status assessment.
Condition
Breeding populations from Bjørnøya, Jan Mayen and West Spitsbergen have generally had a moderate breeding success (<80%) since 2011, 2012, and 2009, respectively. No obvious decline in breeding success was observed (Frederiksen et al. in prep). A previous study (Fluhr et al., 2017) found that adult survival rates on Bjørnøya have declined from 1995/1998 up to approx. 2010 by 9-12% . However, survival rates on Bjørnøya have increased in recent years and average survival on Bjørnøya and Spitsbergen since 2010 has been high (Frederiksen et al. in prep).
In Iceland, BRGUs have had a rather high breeding success and high adult survival in recent years (Frederiksen et al. in prep).
These indicators currently used to assess condition (breeding success and adult survival) provide only partial insights regarding BRGU condition. Changes may have occurred in other demographic parameters such as juvenile survival or breeding probability (Frederiksen et al. in prep). For more information read our latest status assessment.
Threats and impact
Climate change is likely the main threat to BRGU populations breeding in the Northeast Atlantic (Garðarsson, 2006; Descamps et al., 2013; Frederiksen et al., 2016; Fluhr et al., 2017). A climate-related oceanographic shift in the wintering grounds (associated with warming of the ocean) is thought to have resulted in reduced food supplies and concomitantly reduced survival and recruitment rates (Descamps et al., 2013; Fluhr et al., 2017).
Hunting: BRGUs are hunted in Canada and Greenland, and to a lower extent in Iceland (Frederiksen et al., 2016). The winter harvest only partly explains the observed population declines Frederiksen et al., 2019) The potential importance of spring harvest (allowed in Greenland until 2016) and/or illegal harvest during summer has not been investigated but could have played a role in BRGU decline (Merkel et al. 2014)
Predation/disturbance: Disturbance by predators, such as the white-tailed eagle, has likely contributed to the local population declines in northern Norway(Anker-Nilssen et al., 2020, Reiertsen, T.K. and Systad, G., personal communication). This is likely a marginal and very local phenomenon for the BRGU and such disturbance has not been reported elsewhere.
Chemical pollution: Mercury has been detected in feather samples of BRGUs in the Northeast Atlantic (Albert et al., 2021). Higher mean concentrations were detected during the non-breeding season compared to the breeding season, with one population (Isfjorden) exceeding the Hg threshold for seabirds, which may adversely impact health and reproduction (Eisler, 1987).
Oil Pollution: Oiling mortality, which primarily occurs off Newfoundland where only a small proportion of OSPAR breeding populations winter, has decreased substantially in recent decades (Wilhelm et al., 2009; Robertson et al., 2014) and the current impact of this threat on populations in the Northeast Atlantic region is small (Frederiksen et al., 2019).
Bycatch: In the OSPAR region, the impact of fishing activity on BRGUs is negligible as incidental catches are rare (Merkel, 2011; Pálsson et al., 2015; Skarphéðinsson et al., 2016; Bærum et al., 2019; Christensen-Dalsgaard et al., 2019).
Other potential threats may include ingestion of plastics (Provencher et al., 2010; Bond et al., 2013) and disturbance due to hydrocarbon extraction (McFarlane Tranquilla et al., 2013).
For more information read our latest status assessment.