VU
Greater Spotted Eagle Clanga clanga



Justification

Justification of Red List Category
This species has a small population which is suspected to be declining at a rate of >30% over three generations as a result of extensive habitat loss and persistent persecution. It is therefore listed as Vulnerable.

Population justification
In Europe, the breeding population is estimated to number 960-1,300 breeding pairs, equating to 1,900-2,500 individuals (BirdLife International In prep.). Europe forms 25-49% of the global range, so a very preliminary estimate of the global population size is 3,900-10,000 mature individuals, although further validation of this estimate is needed. There is very little data available on population sizes further east in the species's range. National population estimates include: c.100-10,000 breeding pairs, c.50-1,000 individuals on migration and c.50-1,000 wintering individuals in China; < c.50 individuals on migration and < c.50 wintering individuals in Taiwan and c.100-10,000 breeding pairs and c.50-1,000 individuals on migration in Russia (Brazil 2009). Estimates based on known breeding areas in the Volga-Ural region and southwest Siberia and the amount of suitable habitat suggest that the Russian population may be as large as 4,000-4,500 breeding pairs (Karyakin 2008, Karyakin et al. 2012), however, given the vast size of the species's Russian range, further research is necessary to validate this. It is provisionally placed in the band 2,500-9,999 mature individuals.

Trend justification
This species is suspected to have undergone at least a moderately rapid decline over the last three generations as a result of habitat loss and degradation throughout its breeding and wintering ranges, together with the effects of disturbance, persecution and competition with other predators. In Europe, the population size is suspected to have decreased by over 30% in the past 28 years (three generations [Bird et al. 2020]) (BirdLife International In prep.). There is very little data available on population trends further east in the species's range. Information collected and published in the Proceedings of the Vth International Conference on Birds of Prey of Northern Eurasia reported declines since the 20th century in various areas of Russia, including Darvinskyi reserve in northwest Russia  (Babushkin & Kuznecov 2008), southeast Siberia (Elaev 2008) and the Northern Lower-Volga Region (Zavialov & Tabachishin 2008). However, surveys in the south of Western Siberia and the Volga-Ural region suggest that the species is still fairly common in these areas (Karyakin 2008; Karyakin 2012). The global population is provisionally suspected to be declining at a rate of 25-35% based on the decline in the European population, however further research is necessary to understand population dynamics in the Asian part of the species's range. 

Distribution and population

This species occupies a fragmented range, breeding in Estonia, Lithuania, Finland, Poland, Belarus, Russia, Ukraine, Kazakhstan, mainland China and Mongolia (Meyburg et al. 1999; Keller et al. 2020), and potentially in tiny numbers in Pakistan and north-west India (BirdLife International 2001). Passage or wintering birds occur in small numbers over a vast area, including central and eastern Europe, North Africa, East Africa, the Middle East, the Arabian peninsula, the Indian Subcontinent, south Asia and South-East Asia. Wintering birds have also been reported in Hong Kong (China). The population probably numbers fewer than 10,000 mature individuals with Russia holding 2,800-3,000 pairs. The European population is estimated to be 960-1,300 pairs (BirdLife International In prep.). Numbers appear to have declined in the western half of its range and in some parts of its Asian range. However, long-term trends are difficult to assess owing to a lack of data. 

Ecology

It occurs in lowland forests near wetlands, nesting in different types of (generally tall) trees, depending on local conditions. Individuals wintering in the Mediterranean Basin preferentially use salt marshes, coastal lagoons and water courses (Maciorowski et al. 2019). It feeds on unretrieved quarry, small mammals, waterbirds, frogs and snakes, hunting over swamps, wet meadows and, in Europe, over extensively managed agricultural land (A. Lõhmus in litt. 1999); birds soar to c.100 m high when hunting. It is a migratory species, with birds leaving their breeding grounds in October and November to winter in southern Europe, southern Asia and north-east Africa (del Hoyo et al. 1994). They tend to return in February and March. Birds migrate on a broad front, tending to pass in singles, twos and threes with the occasional larger group (Ferguson-Lees and Christie 2001). They do not concentrate at bottleneck sites to the extent of many other raptors such as Clanga pomarina (del Hoyo et al. 1994).

Threats

There is strong evidence of hybridisation between this species and Lesser Spotted Eagle Clanga pomarina (Bergmanis et al. 1997; Lohmus and Vali 2001; Dombrovski 2002; Vali et al. 2010). In some European countries mixed pairs can constitute 50% of Greater Spotted Eagle pairs (Maciorowski and Mizera 2010) or even more (Vali 2011). It is unclear whether this represents a new phenomenon or a conservation concern, but C. pomarina is far more numerous than C. clanga in the zone of overlap, and the range of C. pomarina appears to be spreading east, further into the range of C. clanga.

Habitat destruction poses a significant threat, as suitable habitat mosaics of woodland and wetland have been lost as a result of deforestation and wetland drainage. In eastern Europe, agricultural intensification and the abandonment of traditional floodplain management have reduced foraging habitat quality (A. Lõhmus in litt. 1999). Deforestation in breeding areas poses a threat through loss of nesting sites - in an area in Russia where 40 pairs of Greater Spotted Eagles nested in 2012, half was cut down (I. Karyakin pers. comm. in Maciorowski et al. 2014). Forestry operations are also a major cause of disturbance, as birds are intolerant of human presence in their territories (Maciorowski et al. 2014). Drainage of wet woodland makes them more accessible to predators such as Martes martes (Maciorowski et al. 2014).Wintering habitats are also being lost - in Thailand, low intensity, rain-fed single crop rice are being replaced by multi-cropped intensive rice farms which are less suitable for foraging (P. D. Round in litt. 2016).

Shooting is a threat in Russia, the Mediterranean, South-East Asia and Africa (Brochet et al. 2019; P. D. Round in litt. 1998, P. Mirski in litt. 2012), together with deliberate and accidental poisoning across much of its range (Maciorowski et al. 2014). The poaching of eggs and hatchlings for collectors is also a serious threat (Maciorowski et al. 2014). On migration and at wintering grounds, electrocution, collision with wind turbines, shooting and poisoning are major causes of mortality (Perlman and Granit 2012; Maciorowski et al. 2014). Lead poisoning from consuming waterbirds is a threat in some areas, for example at wintering grounds in Spain (Perez-Garcia et al. 2020).

Conservation actions

Conservation Actions Underway
CITES Appendix II, CMS Appendix I and II. EU Birds Directive Annex I. Raptors MoU Category 1. It is legally protected in Belarus, Estonia, France, Greece, Latvia, Poland, Romania, Russia and Thailand. An International Lesser and Greater Spotted Eagle Working Group has been established. A European action plan was published in 2000 (Meyburg et al. 1999), but given the increase in knowledge and work being conducted on this species in the intervening years it was suggested this plan could be updated (Mirski 2012, I. Burfield in litt. 2013). The first national census was conducted in Belarus during 2000-2002. Research into hybridisation and habitat requirements began in Belarus in 2003. National Action Plans for the species have been produced in Belarus (Dombrovski et al. 2002), Estonia and Ukraine (Domashevsky 2000), and one for Poland has been planned (Mirski 2012). Site protection measures have been initiated at key Belarusian, Polish and Estonian sites, including restricting forestry activities at nest sites during the breeding season.

Conservation Actions Proposed
Survey range and population. Establish long-term monitoring schemes to improve understanding of population trends. Improve understanding of breeding habitat requirements. Protect breeding areas from drainage and rising of infrastructure. Maintain traditional wet meadows. Regulate forestry to minimise disturbance and protect potential nesting trees. Investigate potential threat of hybridisation with C. pomarina. Prevent illegal shooting, poisoning and electrocution. Investigate lead poisoning from feeding on quarry. Raise awareness.

Identification

62-74 cm. Medium-sized, dark eagle. Adult dark brown with slightly paler flight feathers. Underwing-coverts generally darker than flight feathers. Bands of white spots across upperwing of juveniles. In gliding flight, often depresses "hands". Similar spp. Lesser Spotted Eagle A. pomarina is slightly smaller, narrower winged and less stocky. Plumage generally paler and most show contrast between paler underwing and upperwing-coverts and darker flight feathers. Confusion is also possible with adult Steppe Eagle A. nipalenis, Tawny Eagle A. rapax and Eastern Imperial Eagle A. heliaca. Voice Barking kyak during breeding.

Acknowledgements

Text account compilers
Haskell, L.

Contributors
Hilton, G., Löhmas, A., Perlman, Y., Mirski, P., Round, P., Limparungpatthanakij, W., Burfield, I., Capper, D., Khwaja, N., Westrip, J.R.S., Taylor, J., Gilroy, J., Derhé, M., Bird, J., Butchart, S., Peet, N., Shutes, S., Ashpole, J, Wheatley, H. & Pilgrim, J.


Recommended citation
BirdLife International (2022) Species factsheet: Clanga clanga. Downloaded from http://www.birdlife.org on 28/05/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/05/2022.