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===Development of young===
[[File:Aquila clanga MWNH 0815.JPG|thumb|Egg, of greater spotted eagle (Collection [[Museum Wiesbaden]])]]
In Russia, theygreater spotted eagles reportedly seldom lay eggs until May, but sometimes as early as late April, with similar (if mildly earlier) laying times farther west.<ref name= Brown/><ref name= BOTW/> The clutch size is typically two, though sometimes the nest contains one to three eggs.<ref name= Ferguson-Lees/><ref name= Brown/> The eggsEggs are broad ovals that are, grayish -white in colourovoids, and tend to be glossless and often unmarked. However, sometimes they may manifest a few dark brown spots or blotches and sparse grey shell-marks.<ref name= Brown/> The eggs may range in height from {{convert|63|to|74|mm|in|abbr=on}}, and in diameter from {{convert|47.8|to|56.7|mm|in|abbr=on}}.<ref name="Karyakin" /><ref name="Brown" /><ref>Harrison, C. J. O. & P. Castell (2002). ''Bird Nests, Eggs and Nestlings of Britain and Europe with North Africa and the Middle East. Second revised edition''. HarperCollins, London, United Kingdom.</ref>
The incubation stage lasts 42–44 days per most sources, but in southern [[Belarus]], an incubation stage of only 39 days was documented.<ref name="Ferguson-Lees" /><ref name="Dombrovski2">Dombrovski, V. C. (2019). ''Timing, Diet and Parental Care in a Spotted Eagle Nest in Chernobyl Exclusion Zone (Belarus) in 2018 as Revealed by Camera Trap''. Raptors Conservation, 38.</ref> Incubation begins with the first egg.<ref name="Brown" /> The male of the pair was once thought to not to take part in incubation (typically, as in many raptors, they primarily have the responsibility of prey deliveries).<ref name="Brown" /> However, in the aforementioned Belarusian study, the male incubated an average of 57.3 minutes during daylight.<ref name="Dombrovski2" /> ▼The eggs may range in height from {{convert|63|to|74|mm|in|abbr=on}}, with an average of {{convert|67.5|mm|in|abbr=on}} in one sample and {{convert|68.9|mm|in|abbr=on}} in another, by {{convert|47.8|to|56.7|mm|in|abbr=on}} in diameter, with an average of {{convert|54|mm|in|abbr=on}} and {{convert|54.4|mm|in|abbr=on}}.<ref name="Karyakin" /><ref name="Brown" /><ref>Harrison, C. J. O. & P. Castell (2002). ''Bird Nests, Eggs and Nestlings of Britain and Europe with North Africa and the Middle East. Second revised edition''. HarperCollins, London, United Kingdom.</ref>
In the [[Altai Mountains|Altai]] [[taiga]] region, among 6six greater spotted eagle territories, the average brood size was 1.33 nestling per successful nest or 1.0 nestling per occupied nest. Two of the Altai greater spotted eagle territories were on the abandoned territories of eastern imperial eagles.<ref name="Altai">Karyakin, I., Nikolenko, E., & Bekmansurov, R. (2009). ''Results of Monitoring of Greater Spotted Eagle and Imperial Eagle Breeding Groups in the Altai Pine Forests in 2009, Russia''. Raptors Conservation, (17).</ref> Meanwhile, in the Volga-UralVolga–Ural and Western Siberia areas, the mean brood sizes were 1.24 and 1.42, respectively.<ref name="Karyakin" /> ▼▲The incubation stage lasts 42–44 days per most sources, but in southern [[Belarus]], an incubation stage of only 39 days was documented.<ref name="Ferguson-Lees" /><ref name="Dombrovski2">Dombrovski, V. C. (2019). ''Timing, Diet and Parental Care in a Spotted Eagle Nest in Chernobyl Exclusion Zone (Belarus) in 2018 as Revealed by Camera Trap''. Raptors Conservation, 38.</ref> Incubation begins with the first egg.<ref name="Brown" /> The male of the pair was once thought to not to take part in incubation (typically, as in many raptors, they primarily have the responsibility of prey deliveries).<ref name="Brown" /> However, in the aforementioned Belarusian study, the male incubated an average of 57.3 minutes during daylight.<ref name="Dombrovski2" />
The body size between the greater spotted eagle nestlings differs markedly when the second eaglet hatches and the younger usually dies, often via [[siblicide]].<ref name="Brown" /> Competition often resulting in starvation or intentional killing of the younger chick by its elder sibling is not uncommon in birds of prey, especially the eagles, and is often hypothesized as a kind of insurance process wherein the younger sibling acts an insurance if the elder sibling is somehow killed, otherwise the younger sibling (which is not necessarily in ill health) is possibly expected to die.<ref>Simmons, R. (1988). ''Offspring quality and the evolution of cainism''. Ibis, 130(3), 339-357.</ref><ref>Stinson, C. H. (1979). ''On the selective advantage of fratricide in raptors''. Evolution, 1219-1225.</ref> However, this species raises two fledglings at least somewhat more commonly than the lesser spotted eagle.<ref name="Brown" /><ref>Meyburg, B. U. (2002). ''On Cainism in the lesser spotted eagle (Aquila pomarina) and a possible explanation for the phenomenon in this and other eagle species''. Raptors in the New Millennium, 53-61.</ref> Out of 50 nests in the [[Oka Nature Reserve]], though, only one pair managed to produce two fledglings in a year.<ref name="Meyburg2">Meyburg, B. U., & Pielowski, Z. (1991). ''Cainism in the Greater Spotted Eagle Aquila clanga''. Birds of Prey Bull, 4, 143-148.</ref> ▼▲In the [[Altai Mountains|Altai]] [[taiga]] region, among 6 greater spotted eagle territories, the average brood size was 1.33 nestling per successful nest or 1.0 nestling per occupied nest. Two of the Altai greater spotted eagle territories were on the abandoned territories of eastern imperial eagles.<ref name="Altai">Karyakin, I., Nikolenko, E., & Bekmansurov, R. (2009). ''Results of Monitoring of Greater Spotted Eagle and Imperial Eagle Breeding Groups in the Altai Pine Forests in 2009, Russia''. Raptors Conservation, (17).</ref> Meanwhile, in the Volga-Ural and Western Siberia areas, the mean brood sizes were 1.24 and 1.42, respectively.<ref name="Karyakin" />
In an experiment in a nest in Poland, a younger sibling was taken out of the nest to save it ,. withAt the time, the younger eaglet weighingweighed {{convert|310|g|oz|abbr=on}} againstand the older sibling weighed {{convert|1050|g|lb|abbr=on}} for the older sibling at the point of extraction. After being taken out of the nest, the younger eaglet was raised with minimal interactions, to avoid [[Imprinting (psychology)|imprinting]], beyond feeding in captivity by humans. The eaglet shared a cage with an eastern imperial eagle and a lesser spotted eagle , both of which were indifferent towards it, and did not in any way care for or feed the young greater spotted eagleit. At the point of fledgling , the young eagleeaglet was successfully reintroduced to its own parent's nest, fledged , and attained independence.<ref name="Meyburg2" /> ▼▲The body size between the greater spotted eagle nestlings differs markedly when the second eaglet hatches and the younger usually dies, often via [[siblicide]].<ref name="Brown" /> Competition often resulting in starvation or intentional killing of the younger chick by its elder sibling is not uncommon in birds of prey, especially the eagles, and is often hypothesized as a kind of insurance process wherein the younger sibling acts an insurance if the elder sibling is somehow killed, otherwise the younger sibling (which is not necessarily in ill health) is possibly expected to die.<ref>Simmons, R. (1988). ''Offspring quality and the evolution of cainism''. Ibis, 130(3), 339-357.</ref><ref>Stinson, C. H. (1979). ''On the selective advantage of fratricide in raptors''. Evolution, 1219-1225.</ref> However, this species raises two fledglings at least somewhat more commonly than the lesser spotted eagle.<ref name="Brown" /><ref>Meyburg, B. U. (2002). ''On Cainism in the lesser spotted eagle (Aquila pomarina) and a possible explanation for the phenomenon in this and other eagle species''. Raptors in the New Millennium, 53-61.</ref> Out of 50 nests in the [[Oka Nature Reserve]], though, only one pair managed to produce two fledglings in a year.<ref name="Meyburg2">Meyburg, B. U., & Pielowski, Z. (1991). ''Cainism in the Greater Spotted Eagle Aquila clanga''. Birds of Prey Bull, 4, 143-148.</ref>
The mother greater spotted eagle can be a somewhat tight sitter , but can abandon the nest when disturbed by activity , incan aabandon Belarusianthe studynest for a full day before returning.<ref name="Brown" /><ref name="Dombrovski2" /> By late July to early August, the young are fully feathered, soonand takeswithin itsfive firstdays flightthereafter intake nottheir morefirst than 5 daysflight.<ref name="Brown" /> [[Fledgling is(bird)|Fledging]] occurs at 60–67 days, averaging close to 62 days.<ref name="Ferguson-Lees" /> In the Altai-Sayan region, the mean number of fledglings per successful nest could vary from aan meanaverage of 1 per nest in [[Tuva]] to 1.8 in [[Khakassia]].<ref name="Karyakin3" /> In Kazakh studies, aan meanaverage of 1.38 fledglings were produced in 11 nests.<ref name="Levin" /> In [[Western Siberia]], aan meanaverage of 1.44 fledglings were produced in 66 broods.<ref name="Karyakin5">Karyakin, I. V. (2008). ''Ecology of the Greater Spotted Eagle in Western Siberia''. — Research and Conservation of the Spotted Eagles.</ref> ▼▲In an experiment in a nest in Poland, a younger sibling was taken out of the nest to save it, with the younger eaglet weighing {{convert|310|g|oz|abbr=on}} against {{convert|1050|g|lb|abbr=on}} for the older sibling at the point of extraction. After being taken out of the nest, the younger eaglet was raised with minimal interactions, to avoid [[Imprinting (psychology)|imprinting]], beyond feeding in captivity by humans. The eaglet shared a cage with an eastern imperial eagle and a lesser spotted eagle both of which were indifferent towards and did not in any way care for or feed the young greater spotted eagle. At the point of fledgling the young eagle was successfully reintroduced to its own parent's nest, fledged and attained independence.<ref name="Meyburg2" />
Further dependenceDependence on the parents lasts to 30 days more after fledglingfledging.<ref name="Ferguson-Lees" /> Before dispersing for good, the young greater spotted eagles may wander locally into the open steppe for a little while.<ref name="Brown" /> Female greater spotted eagles were found to leave 2–3 days before their young in a study in Poland. Meanwhile, the male tends to leave last, at about 1 week after the female. In the Polish study, adults headed straight for [[Bosphorus]] while juveniles were sometimes less direct.<ref name="Meyburg3">Meyburg, B., Meyburg, C., Mizera, T., Maciorowski, G., & Kowalski, J. (2005). ''Family break up, departure, and autumn migration in Europe of a family of Greater Spotted Eagles (Aquila clanga) as reported by satellite telemetry''. Journal of Raptor Research, 39(4), 462.</ref> Most were gone from Poland by the end of September ,. juvenilesJuveniles alsowere seen to wander in elsewhere in Poland during autumn before finally migrating.<ref name="Meyburg3" /> ▼▲The mother greater spotted eagle can be a somewhat tight sitter but can abandon the nest when disturbed by activity, in a Belarusian study for a full day before returning.<ref name="Brown" /><ref name="Dombrovski2" /> By late July to early August, the young are fully feathered, soon takes its first flight in not more than 5 days.<ref name="Brown" /> Fledgling is at 60–67 days, averaging close to 62 days.<ref name="Ferguson-Lees" /> In Altai-Sayan region, the mean number of fledglings per successful nest could vary from a mean of 1 per nest in [[Tuva]] to 1.8 in [[Khakassia]].<ref name="Karyakin3" /> In Kazakh studies, a mean of 1.38 fledglings were produced in 11 nests.<ref name="Levin" /> In [[Western Siberia]], a mean of 1.44 fledglings were produced in 66 broods.<ref name="Karyakin5">Karyakin, I. V. (2008). ''Ecology of the Greater Spotted Eagle in Western Siberia''. — Research and Conservation of the Spotted Eagles.</ref>
▲Further dependence on the parents lasts to 30 days more after fledgling.<ref name="Ferguson-Lees" /> Before dispersing for good, the young greater spotted eagles may wander locally into the open steppe for a little while.<ref name="Brown" /> Female greater spotted eagles were found to leave 2–3 days before their young in a study in Poland. Meanwhile, the male tends to leave last, at about 1 week after the female. In the Polish study, adults headed straight for [[Bosphorus]] while juveniles were sometimes less direct.<ref name="Meyburg3">Meyburg, B., Meyburg, C., Mizera, T., Maciorowski, G., & Kowalski, J. (2005). ''Family break up, departure, and autumn migration in Europe of a family of Greater Spotted Eagles (Aquila clanga) as reported by satellite telemetry''. Journal of Raptor Research, 39(4), 462.</ref> Most were gone from Poland by the end of September, juveniles also seen to wander in elsewhere in Poland during autumn before finally migrating.<ref name="Meyburg3" />
===Hybridization===
At one time, it is possible that greater and lesser spotted eagles weremay have been largely isolated from each other via different habitat(though usage,potentially althoughproximal) thehabitat ranges may have long since abutted one anotherusage.<ref name= Helbig2/> Climate changes at the conclusion of the [[Last Glacial Period|last ice age]] (at some point early in the [[Holocene]]) permitted forest growth where there were once grassy boundaries, allowing the two species of spotted eagles to expand into each other’s ranges.<ref name= Helbig2/><ref>Lõhmus, A., & Väli, Ü. (2001). ''Interbreeding of the greater Aquila clanga and lesser spotted eagle A. pomarina''. Acta ornithoecol, 4, 377-384.</ref> Hybridization is now known to occur extensively. with hybridsHybrids occurringoccurs in the entire overlapping range of the two species, which is some {{convert|600000|km2|sqmi|abbr=on}},. withInterbreeding interbreedingis mostly determined via conjecture in the [[European Russia]] area, wherewhich hybridizationis possibly occurred the most recently (this beingroughly the eastern limits roughlylimit of the lesser spotted eagle’s range) and thus where hybridization possibly occurred most recently.<ref name= Vali/><ref name= Shukov/><ref>Meyburg, B. U., & Meyburg, C. (2007). ''Post-fledging behavior and outward migration of a hybrid Greater× Lesser Spotted Eagle (Aquila clanga× A. pomarina)''. Journal of Raptor Research, 41(2), 165-170.</ref>
Hybrids between the species often show a nape patch, absent in pure greater spotted eagles, an intermediate amount of spotting about the wings and a typically larger body size than pure lesser spotted eagles.<ref name="Vali2004">{{cite journal |last1=Väli |first1=Ülo |last2=Lõhmus |first2=Asko |year=2004 |title=''Nestling characteristics and identification of the lesser spotted eagle Aquila pomarina, greater spotted eagle A. clanga, and their hybrids'' |journal=[[Journal of Ornithology]] |volume=145 |issue=3 |pages=256–263 |doi=10.1007/s10336-004-0028-7|s2cid=20893726 }}</ref> Despite their intermediate characteristics and larger size than lesser spotteds, the hybridization of the species is thought to be an indication of the abandonment of greater spotted eagle territories and the replacement of them by the more adaptive and populous lesser spotted eagles, as was indicated in an Estonian study.<ref name="Vali" />
TheHybrids Estonianbetween studythe reflectedtwo thatspecies often show a nape patch (absent in pure greater spotted eagles), an intermediate amount of spotting about the numberwings, and typically a larger body size than pure lesser spotted eagles.<ref name="Vali2004">{{cite journal |last1=Väli |first1=Ülo |last2=Lõhmus |first2=Asko |year=2004 |title=''Nestling characteristics and identification of hybridthe lesser spotted eagle Aquila pomarina, greater spotted eagle A. clanga, and their hybrids'' |journal=[[Journal of Ornithology]] |volume=145 |issue=3 |pages=256–263 |doi=10.1007/s10336-004-0028-7|s2cid=20893726 }}</ref> Despite their intermediate characteristics and larger size than lesser spotteds, the hybridization of the species is thought to be an indication of the abandonment of greater spotted eagle pairsterritories wasand twicethe replacement of them by the more adaptive and populous lesser spotted eagles, as highwas indicated in an Estonian study.<ref name="Vali" /> The Estonian study found that the number of pairs of hybrids in the nation thanwas twice that of pure greater spotted eagles.<ref name="Vali" /> The situation was even graver in [[Lithuania]], where not a single pure pair of greater spotted eagles could be found any longer by the mid-2000s, with only 2.7% of 161 breeding spotted eagles being greater spotteds, the rest being lesser spotted eaglesspotteds.<ref name="Treinys">Treinys, R. (2005). ''The Greater Spotted Eagle (Aquila clanga): previous, current status and hybridisation in Lithuania''. Acta zoologica lituanica, 15(1), 31-38.</ref> Lesser spotted eagles were estimated to number around 10001,000 breeding pairs in Lithuania, with an estimated 37 or so of these containing one mate that iswas a greater spotted eagle.<ref name="Treinys" />
Both Polish and Estonian studies reflected a probable high turnover of mates in hybrid pairs, with the Polish data finding about 71% of the males of the pairs being supplemented in subsequent years.<ref name="Vali" /><ref name="Maciorowski4">Maciorowski, G., Mirski, P., & Väli, Ü. (2015). ''Hybridisation dynamics between the Greater Spotted Eagles Aquila clanga and Lesser Spotted Eagles Aquila pomarina in the Biebrza River Valley (NE Poland)''. Acta Ornithologica, 50(1), 33-41.</ref> Furthermore, the Polish data shows that the hybrids are favouring the habitats of lesser spotted eagles farther away from the wetter habitats of the greater spotted eagle and often nearer human development, with a local 50% reduction of pure greater spotted eagle pairs and 30% increase in hybrid pairs.
The habitatHabitat alterations to the environment by humans are thought in general to be partially beneficial to lesser spotted eagles and normally harmful to greater spotted eagles.<ref name="Maciorowski4" /><ref>Maciorowski, G., & Mirski, P. (2014). ''Habitat alteration enables hybridisation between lesser spotted and greater spotted eagles in north-east Poland''. Bird Conservation International, 24(2), 152-161.</ref>
==Status and conservation==
[[File:Greater spotted eagle.jpg|thumb|left|Wintering greater spotted eagle in [[Israel]].]]
Despite maintaining a fairly vast breeding range, coveringrange—covering at least 9 million square kilometres, in a band from the [[Baltic Sea]] in Europe right acrosseastward to the [[Pacific Ocean]] with minor outpostoutposts in the Indian subcontinent, thissubcontinent—this eagle occurs at extremely low densities.<ref name= Ferguson-Lees/>
The populationsPopulations and trends of the species have been considered fairly poorly studied in the past, but a strong declining trend has been detected.<ref name="Ferguson-Lees" /><ref name="BOTW" /> Rough estimates in the 1990s indicated some 11 pairs in a huge area of northeastern Poland, around {{convert|2000|km2|sqmi|abbr=on}} in northeastern Poland, and only some 20-3020–30 pairs in a huge studyan area of {{convert|85000|km2|sqmi|abbr=on}} in European Russia, with no more than 900 pairs west of the Urals.<ref name="Ferguson-Lees" /> More refined subsequent efforts put the number of breeding pairs in the European Union at 810 to 1100810–1,100 breeding pairs.<ref name="GRIN" />
Furthermore, in the 1990s, it was extrapolated from Indian wintering populations that the more eastern population is surely less than four figures.<ref name="Ferguson-Lees" /> [[Birdlife International]] in the 1990s estimated the Russian population at 2800-30002,800–3,000 pairs. More recently, Birdlife has estimated the global population as no more than 3800-133,800–13,200 total mature individuals worldwide.<ref name="iucn status 11 November 2021" /><ref name="Ferguson-Lees" /><ref name="BOTW" />
ColorA color-banding recovery studies havestudy determined that of 13701,370 European bandbanded recoveries of spotted eagles, only 3.6% were greater spotted eagles, while hybridhybrids greater xof lesser spottedand eaglesgreater spotteds comprised 2.7%, and the remaining numbering beingwere all lesser spotted eagles.<ref>Dravecký, M., Sellis, U., Bergmanis, U., Dombrovski, V., Lontkowski, J., Maciorowski, G., Maderic, B., Meyburg, B. U., Mizera, T., Stoj, M., Treinys, R. & Wójciak, J. (2008). ''Colour ringing of the Spotted Eagles (and their hybrids) in Europe-a review''. Raptor Journal, 2(2008), 37-52.</ref> Greater spotted eagles are considered [[Local extinction|extripated]] as a breeding species from [[Hungary]], [[Romania]], [[Bulgaria]], [[Czech Republic]] (where they may have never consistently bred), and [[Slovakia]], as well as [[Israel]] where they last bred in the 1960s. Meanwhile, the Finland breeding population is also likely almost gone.<ref name="Ferguson-Lees" /><ref name="BOTW" /><ref name="GRIN" />
Steady reduction in Ukraine down to 40-5040–50 pairs by 1985, and a 12-2012–20% overall reduction of the Ukrainian population wasfrom estimated, fromthe 1920s to 1990s was estimated.<ref name="Ferguson-Lees" /><ref>Gorban, I. (1996). ''Lesser and Greater Spotted Eagle Aquila pomarina and A. clanga in Ukraine''. Eagle Studies. World Working Group on Birds of Prey, Berlin, London & Paris, 301-302.</ref> The numbersnumber of greater spotted eagles in Estonia declined 14% in the period merely from 2004 to 2010, with declines having been detected for some time there.<ref name="Vali2" /><ref>Volke, V. (1996). ''The status of the Greater Spotted Eagle Aquila clanga and Lesser Spotted Eagle A. pomarina in Estonia''. Eagle studies, 285-289.</ref> The number of breeding pairs in Belarus ishas as many 150-200as 150–200 breeding pairs (with confirmed counts of somewhat over 100 breeding pairs) and this is considered the most important breeding area known outside of Russia.<ref name="GRIN" />
WhereWhereas the total numbers in European Russia were once estimated at around 10001,000 breeding pairs in the 1960s, itthere isare estimated thatto there arebe fewer than 700 pairs leftremaining there.<ref name="BOTW" /><ref>Kalyakin, M. V., & Voltzit, O. V. (2006). ''The Atlas of the Birds of Moscow City Project: history, methods and first results''. Bird Census, 63.</ref> The species' range has shrunk in the [[Russian Far East]], where it once widely found but is now restricted to below the middle [[Amur]] river, along the [[Ussuri]] river, and south [[Primorsky Krai|Primorsky]], although anecdotal information suggests that it is still somewhat common in the whole [[Western Siberia]]n lowlands from the [[Ural Mountains]] to the middle [[Ob River]].<ref name="BOTW" /> In Kazakhstan, there are an estimated 74-9774–97 breeding pairs of the species.<ref name="Levin" />
Wintering estimates are more scattered and efforts to tabulate numbers in India show they continue to occur quite broadly, but in perhaps slightly lowered and more scattered numbers.<ref name="Naoroji" /><ref>Hussain, M.M., A. Doley, R. Dutta & H. Singha (2019). ''Sighting of Greater Spotted Eagle Clanga clanga in Assam University, Silchar Campus with its current distribution in Assam, India''. Bird-osoar #34, In: Zoo’s Print 34(9): 17–26.</ref><ref>Santhakumar, B., Ali, A. M. S., & Arun, P. R. (2016). ''Status of Greater Spotted Eagle Clanga clanga in Tamil Nadu and Puducherry, India''. Indian Birds, 11, 71-74.</ref><ref>Kataria, A. K., Kataria, N., & Kumawat, R. N. (2016). ''Effect of environmental elements on migration pattern of eagles at Jorbeer conservation reserve, Bikaner, Rajasthan, India''. Research Journal of Life Sciences, Bioinformatics, Pharmaceuticals and Chemical sciences, 2016c, 2(3), 90-101.</ref> In Armenia, it is considered one of the two rarest of the nation’s 30 raptor species, along with the eastern imperial eagle.<ref>Ananian, V. (2008). ''On the finds of Greater Spotted Eagle in Armenia''. Изучение и охрана большого и малого подорликов в Северной, 34.</ref> Wintering numbers of greater spotted eagles in the Mediterranean Basin were found to total about 300-400300–400 individuals, with a bit under 34% of these in Israel, just under 32% in Greece, 16% in Turkey, somewhat smaller numbers in Romania and Spain, and tiny numbers in [[Southeastern Europe]], Montenegro, and France.<ref name="Maciorowski" /> Around 50 individuals winter in Turkey per other sources.<ref name="Esra" /> The species appears fairly rarely in Ethiopia and Eritrea, where they are seen singly and sparsely in most cases.<ref name="Ash" />
The species appears fairly rarely in Ethiopia and Eretria where they are seen singly and sparsely in most cases.<ref name="Ash" /> In essentially every nation of its distribution, the greater spotted eagle has a [[Vulnerable species|Vulnerable]] status.<ref name="GRIN" /> As a species, the greater spotted eagle is classified as [[Vulnerable species|vulnerable]] to [[extinct]]ion by the [[IUCN]].<ref name="iucn status 11 November 2021" />
===Threats and conservation efforts===
[[File:Greater Spotted Eagles (29573045537).jpg|thumb|left|A couple of greater spotted eagles wintering in India.]]
The species' primary threats are habitat degradation and habitat loss.<ref name="iucn status 11 November 2021" /><ref name= BOTW/> Greater spotted eagles appear to be highly sensitive to habitat alterations, especially drainage of wetlands, intensified agricultural practices, and abandonment of floodplain management practices.<ref name= Maciorowski2/><ref name=Vali2000>{{cite journal |last1=Väli |first1=Ülo |last2=Lõhmus |first2=Asko |year=2000 |title=''Suur-konnakotkas ja tema kaitse Eestis'' |trans-title=''The Greater Spotted Eagle and its conservation in Estonia'' |journal=Hirundo |volume=Supplement 3 |pages=1–50 |url=http://www.eoy.ee/hirundo/supplementumid/69/supplementum-3-2000}}</ref>
Detrimental wetland management processes have additionally effectedaffected the species on their wintering grounds, where in Saudi Arabia at least, the effect has been offset by the greater spotted eaglesspecies adapting to man-made bodies of water (unlike in winter, though, there is no evidence that they adapt well to man-made areas during breeding).<ref>Khaleghizadeh, A. (2004). ''Notes on three rare raptors in the Anzali wetlands, Iran''. Sandgrouse. 26(2): 155.</ref><ref>Meadows, B.S. (2011). ''A note on occurrence at man-made habitats of wintering Greater Spotted Aquila clanga and Eastern Imperial Eagles A. heliaca in the coastal belt of eastern Saudi Arabia''. Sandgrouse. 33(2): 98-101.</ref> The amount of usable manmade habitatshabitat has shrunk in Thailand with a change to dry season rice field cropping and the creeping presence of urbanization, along with probable [[rodenticide]] usage and other poisonings, likely harming numbersthe number of the species able to winter there.<ref name="Mallalieu" />
Other threats are known tothreats include human disturbance during the mating season, with forestry operations known now known to be a major cause of disturbance at the nest site.<ref name="BOTW" /><ref name="Vali2000" /> Furthermore, greater spotted eagles are threatened by mostly inadvertent poisonings and collisions with man-made objects, especially electrical [[wire]]s.<ref name="Ferguson-Lees" /><ref>Dixon, A., Maming, R., Gunga, A., Purev-Ochir, G., & Batbayar, N. (2013). ''The problem of raptor electrocution in Asia: case studies from Mongolia and China''. Bird Conservation International, 23(4), 520-529.</ref> Poisonings were known to be a serious cause of mortality in a [[Shanxi]] reserve ofin China, where the eagles were seen to hunt down sickly or dying [[common pheasant]]s (''Phasianus colchicus'') that had been poisoned and then subsequently dying themselves, this becoming the primary local source of mortality.<ref name="BOTW" /><ref>Quigxia, Z. (1996). ''Winter ecology of Aquila clanga in Lishan Nature Reserve''. Sichuan Journal of Zoology 15: 170-172.</ref>
In the Malay Peninsula, subsequent to a brief increase of the species from the 1960s to the 1980s due to environmental changes favorable to avian scavengers, a crash in numbers down to almost none there was thought to be quite likely due to pesticide and other poison usage.<ref name="GRIN" /><ref name="Wells" /> The real trends of greater spotted eagles are sometimes masked by misidentifications.<ref name="Ferguson-Lees" />
Furthermore, as aforementioned, the species is at threat of hybridization and ultimate supplantingsupplantation by the lesser spotted eagle as that species’its range creeps farther east.<ref name="Helbig2" /><ref name="Vali" /> The greater spotted eagle is legally protected in aonly scattered amount of nations, making conservation efforts difficult.<ref name="iucn status 11 November 2021" /><ref name="BOTW" /> Among the nations where they are legally protected are Belarus, Estonia, France, Greece, Latvia, Poland, Romania, Russia, and nominally in Thailand. A working group specifically to address spotted eagles has been established as of the 21st century.<ref name="iucn status 11 November 2021" /><ref name="BOTW" /><ref name="Group">Meyburg, B. U., Haraszthy, L., Strazds, M., & Schäffer, N. (2001). ''European species action plan for greater spotted eagle. European Union Action Plans for Eight Priority Birds Species''. Europ Comm, Luxembourg.</ref> The working groups have managed to undertake conservation efforts in Belarus, Estonia, and the Ukraine, among theUkraine—the core breeding areas left in Europe for the speciesspecies—and and they’vehave successfully instituted restrictions ofon forestry activities near the nestnesting sites during the breeding season.<ref name="iucn status 11 November 2021" /><ref name="BOTW" /><ref name="Group" />
The building of artificial nest platforms did not seem to greatly aid greater spotted eagles in Nizhny Novgorod, unlikeNovgorod—unlike other raptors such as the [[osprey]], the [[white-tailed eagle]] (''Haliaeetus albicilla''), and the [[golden eagle]], as—as only one pair of greater spotted eagles were recorded to use a platform as a nest and higher survey numbers of greater spotted eagles in that region were likely only due to more extensive surveying.<ref name="Shukov" /><ref>Bakka, S. V., Kiseleva, N. Y., & Shukov, P. M. (2020). ''Installing of Artificial Nests as a Method of the Large Birds of Prey Population Management in the Center of European Russia: Successes, Problems, Prospects''. In IOP Conference Series: Earth and Environmental Science (Vol. 543, No. 1, p. 012015). IOP Publishing.</ref> In an exceptional positive note, it was found the European population of greater spotted eagle, as studied via [[microsatellite]]s, retains quite high genetic diversity, meaning that there is no eminent threat of a [[Population bottleneck|genetic bottleneck]] for the species.<ref name="Helbig2" /><ref>Väli, Ü., Dombrovski, V., Dzmitranok, M., Maciorowski, G., & Meyburg, B. U. (2019). ''High genetic diversity and low differentiation retained in the European fragmented and declining Greater Spotted Eagle (Clanga clanga) population''. Scientific reports, 9(1), 1-11.</ref><ref>Väli, Ü., Treinys, R., & Poirazidis, K. (2004). ''Genetic structure of Greater Aquila clanga and Lesser Spotted Eagle A pomarina populations: implications for phylogeography and conservation''. Raptors Worldwide. World Working Group on Birds of Prey & BirdLife Hungary, Budapest, 473-482.</ref>
==References==
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