VU
Eastern Imperial Eagle Aquila heliaca



Justification

Justification of Red List category
This species has a small global population, and is likely to be undergoing continuing declines, primarily as a result of habitat loss and degradation, adult mortality through persecution and collision with powerlines, nest robbing and prey depletion. It is therefore listed as Vulnerable. More information is needed to confirm the size and trends of populations in Asia. Should this information show that the population is larger than currently thought, or declining at a more moderate rate, the species will warrant downlisting to a lower threat category.

Population justification
In Europe, the breeding population was estimated to number 1,300-1,900 breeding pairs, equating to 2,500-3,800 mature individuals. Recent population estimates from Russia and Kazakhstan suggest the global population may exceed 10,000 mature individuals, but in light of criticism of these estimates the population is precautionarily retained in the band 2,500-9,999 mature individuals here. This equates to 3,750-14,999 individuals in total, rounded here to 3,500-15,000 individuals.

Trend justification

The European population (comprising c.30% of the global range) is estimated to be increasing (BirdLife International 2015), though local increases may be partly due to immigration as well as increased fecundity and survival (Demerdzhiev et al. 2015). Recent reports from Russia and Kazakhstan indicate these populations may be stable, with some local population increases (I. Karyakin in litt. 2016) however, these reports need further confirmation as the population in Russia is suspected to undergo a decline in the future due to the presence of threats at breeding sites. As such, the global population of this species is precautionarily estimated to remain in decline, owing to habitat loss and exploitation across its range.

Distribution and population

This species breeds in Austria, Azerbaijan, Bulgaria, China, Czech Republic, Macedonia, Georgia, Greece, Hungary, Kazakhstan, Russia, Mongolia, Serbia, Slovakia, Turkey and Ukraine (Heredia 1996, M. Horváth & I. Karyakin in litt. 2016). The species possibly breeds or is found in very small numbers in Armenia, Croatia, Cyprus, Greece, Kosovo, Moldova and Romania (BirdLife International 2015). In addition, breeding has not been proved but possibly occurs in Afghanistan, Iran, Kyrgyzstan, Pakistan, Tajikistan, Turkmenistan and Uzbekistan. On passage and in winter, birds are found in the Middle East, east Africa south to Tanzania, the Arabian peninsula, the Indian Subcontinent and south and east Asia (from Thailand to Korea). The European population is estimated at 1,300-1,900 pairs, which equates to 2,500-3,800 mature individuals (BirdLife International 2015). This estimate alongside a previous estimate of 1,800-2,200 pairs for the period 2000-2010 (Demerdzhiev et al. 2011) is higher than previous estimates of 1,051-1,619 pairs reported in 2000 (Horváth et al. 2002) and 1,110-1,624 pairs in 2008 (BirdLife International 2008, Barov and Derhé 2011), and is partly due to increased survey effort rather than a genuinely large population increase. There was a rapid decline in Europe and probably in Asia in the second half of the 20th century. Recently the central European population (240-260 pairs mostly in Hungary and Slovakia [M. Horváth in litt. 2016]) appears to have been increasing (Horváth et al. 2005, Demerdzhiev et al. 2011, BirdLife International 2015) as a result of conservation efforts, although the majority of the threats to the species persist (D. Horal in litt. 2012). In the last six years the occurrence of persecution incidents significantly increased (Horváth et al. 2011), with more than 70 Eastern Imperial Eagles poisoned in Hungary (M. Horváth in litt. 2016). The Balkan population (76-132 pairs mostly in Bulgaria and Macedonia [Demerdzhiev et al. 2011] ) is apparently stable (although the last proven breeding in Greece took place in 1993). Recent surveys in Azerbaijan found relatively high densities in the north-western plains, estimating 50-60 pairs within a 6,000 km2 study area (Horváth et al. 2007), and a total population size of 50-150 pairs (Horváth et al. 2008, Sultanov 2010). This suggests that the Caucasian population may have been underestimated (it was previously assumed that less than 50 pairs bred in Azerbaijan and Georgia) (Horváth et al. 2007), and the population of Turkey may also have been underestimated with 32 pairs found in European Turkey and another 50 in north-west Anatolia (Demerdzhiev et al. 2014, Horváth et al. 2014). However, a large proportion of these Turkish nesting areas are threatened by intensive infrastructural development and habitat loss (M. Horváth in litt.  2016). Populations in the Volga Region of Russia are relatively stable, but are suspected to decline in the future due to the presence of threats at breeding sites (M. Korepov and R. Bekmansurov in litt. 2012). At least half of the world population (and possibly more) breeds in Russia (900-1,000 pairs [Belik et al. 2002]) and Kazakhstan (750-800 pairs [Bragin 1999]). More recent surveys conducted by Karyakin et al. (2008, 2011, 2013) estimated 3,000-3,800 pairs in Russia and 3,200-4,000 pairs in Kazakhstan, which includes the breeding population in western Kazakhstan increasing from 1 pair in 2006 to 34 pairs in 2015, with all of the new pairs consisting of young birds (I. Karyakin in litt. 2016). However further studies are required to gain more precise population size and trend estimates for the species in these countries. Although these populations currently seem to be stable, the Russian population has been predicted to decline [V. Galushin in litt. 1999].

Ecology

This is a lowland species that has been pushed to higher altitudes by persecution and habitat loss in Europe. In central and eastern Europe, it breeds in forests up to 1,000 m and also in steppe and agricultural areas with large trees, and nowadays also on electricity pylons. In the Caucasus, it occurs in steppe, lowland and riverine forests and semi-deserts. Eastern populations breed in natural steppe and agricultural habitats. Both adults and immatures of the eastern populations are migratory, wintering in the Middle East, East Africa south to Tanzania, the Arabian peninsula, the Indian Subcontinent and south and east Asia; wintering birds have also been reported in Hong Kong (China). These birds make their southward migration between September and November, returning between February and May (Ferguson-Lees and Christie 2001). Wetlands are apparently preferred on the wintering grounds. Birds are usually seen singly or in pairs, with small groups sometimes forming on migration or at sources of food or water (Ferguson-Lees and Christie 2001). In exceptional cases large groups of up to 200 have been known to form on autumn migration (Snow and Perrins 1998). Adults in central Europe, the Balkan peninsula, Turkey and the Caucasus are usually residents, whilst some immatures move south. Non-territorial birds often associate with other large eagles such as A. clanga and Haliaeetus albicilla on wintering and temporary settlement areas.

Threats

Breeding sites are threatened primarily by intensive forestry in the mountains, and by the shortage of large indigenous trees in the lowlands (e.g. illegal tree cutting affected several pairs in Russia [Karyakin et al. 2009a] and Bulgaria). The species is sensitive to human disturbance, which means its breeding range can be highly restricted by human presence and infrastructural development in Central Europe (and probably elsewhere in its range e.g. Karyakin 2011) (M. Horváth in litt. 2016). Infrastructural and settlement network was the primary cause for the absence of the species at more than 30% of its potential habitats at the Hungarian Plain (Horváth 2009). 
Other threats are loss and alteration of feeding habitats, shortages of small and medium-sized prey species (particularly ground-squirrels Spermophilus spp.), nest robbing and illegal trade, shooting, poisoning, electrocution by powerlines and collisions with vehicles. An average of c.450 Eastern Imperial Eagles were killed by powerlines during the 2009 breeding season in the Altai region – 25% of the total population of the region (Karyakin et al. 2009b). Habitat alterations associated with agricultural expansion threaten historical and potential breeding sites in former range countries. In Central Europe intentional predator poisoning became the first cause of mortality from 2006 onwards affecting more than 80 specimens in 10 years only in Hungary (Horváth et al. 2011, M. Horváth in litt. 2016). Hunting, poisoning, prey depletion and other mortality factors are also likely to pose threats along migration routes and in wintering areas. Competition for nest sites with Greater Spotted Eagle Aquila clanga has been reported in the Altai region, Russia (Karyakin et al. 2009c).

Conservation actions

Conservation Actions Underway
CITES Appendix I and II. CMS Appendix I and II. EU Birds Directive Annex I. It is legally protected in Armenia, Azerbaijan, Bulgaria, Croatia, Georgia, Greece, Hungary, Romania, Slovakia, Turkey and Ukraine. The Eastern Imperial Eagle Working Group was established in 1990. A European action plan was published in 1996 (Heredia 1996) and its implementation reviewed in 2010 (Barov and Derhé 2011). Regional Action Plans have been published for the Balkan Peninsula (Stoychev et al. 2004) and for the Southern Caucasus (Horváth et al. 2006). The Eastern Imperial Eagle Management Guidelines for Hungary were published in 2005 (Kovács et al. 2006) and for Slovakia in 2007 (Demeter and Maderič 2007). Bulgarian Society for the Protection of Birds has purchased 70 ha of pastureland inhabited by ground-squirrels, in known areas where juvenile eagles congregate in an attempt to protect the ground-squirrels and the eagles that rely on them for food (Anon. 2013). The provision of nesting platforms has been shown to aid in local population increases (Shashkin et al. 2011).

Conservation Actions Proposed
Conduct further surveys in Eastern Europe and Asia (particularly Russia, Kazakhstan, Turkey and the Caucasus) to determine population size and trends (M. Horváth in litt. 2016). Conduct surveys to identify breeding and wintering sites, and migration routes. Improve protection of species and sites. Implement beneficial forestry policies. Maintain large trees in open land and protect old woodland on slopes (B. Hallmann in litt. 1999). Prevent mortality from poisoning, electrocution on medium-voltage powerlines, nest robbing, nest destruction and illegal trade as well as persecution in wintering grounds and migratory routes. Maintain feeding habitats by preserving traditional land use. Increase the availability of prey species by habitat management. Raise public awareness and involve stakeholders in conservation activities.

Identification

75-84 cm. Large, dark eagle. Generally dark brown with white scapular markings and pale golden-cream nape. Grey base to tail. Juvenile brown fading to pale buff with dark flight feathers. Shows flat wings in flight. Similar spp. Golden Eagle A. chrysaetos is paler with less obviously bi-coloured tail. Holds wings in flattened "V" shape. Steppe Eagle A. nipalensis lacks pale rusty yellow ventral area, bi-coloured tail and pale scapulars. Voice Repeated barking.

Acknowledgements

Text account compilers
Harding, M., Pople, R., Butchart, S., Ashpole, J, Bird, J., Benstead, P., Westrip, J., Khwaja, N., Derhé, M., Gilroy, J.

Contributors
Bekmansurov, R., Galushin, V.M., Gradev, G., Hallmann, B., Heredia, B., Horal, D., Horváth, M., Karyakin, I., Katzner, T., Korepov, M., Kovács, A., Moshkin, A., Mátyás, P., Ryabtsev, V., Stanislav, V., Stoychev, S. & Velevski, M.


Recommended citation
BirdLife International (2024) Species factsheet: Eastern Imperial Eagle Aquila heliaca. Downloaded from https://datazone.birdlife.org/species/factsheet/eastern-imperial-eagle-aquila-heliaca on 24/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 24/12/2024.