Khan of the steppe

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Steppe Eagle (Aquila nipalensis) is the largest bird of prey breeding in open steppes and semi-deserts of Eurasia. Other eagles crossing the steppe belt during migration do not breed in the open and normally need trees or cliffs for nesting. It is the only eagle to have adapted to nesting on the ground in treeless and flat landscapes, although sometimes it builds nests on trees and rocky hills. Majestic posture, imposing gaze and absence of enemies, with the exception of wolves and humans, make this bird a true winged khan of the steppe.

  

 

 

 

 

 

 

 

 

 

 

Steppe Eagle breeding range stretches from Kalmykia in Russia to north-eastern China, but despite of such wide distribution, the overall species population size is unknown and the species is believed to have suffered significant declines across its range.

 

Steppe Eagle nests can sometimes be found very close to roads, however such roads are normally very rarely used. One possible reason to build nests on a side of a raised road is the advantage of higher ground improving overview of the surrounding territory for the incubating bird. If a potential predator is spotted well in advance, female will have enough time to either leave the nest unnoticed or lay low in it, depending on a predator. Another possible advantage of such location for a nest is proximity to powerline pylons, which are very often used by steppe eagles as lookout perches.


 

Some pairs in search for safety are building their nests on powerline pylons. Owing to their construction, types of pylons shown below are relatively safe for the eagles. But there are thousands of kilometres of poorly designed or old powerlines stretched across the steppes, some of which are remnants of Soviet time infrastructure, some are newly built. Such powerlines can be particularly deadly for many species of birds of prey, including Steppe Eagles, owing to the increased chance of electrocution. This is considered to be one of the main threats to the species, but unfortunately, very little is done currently in the region to make such lines safe for birds.


 

Breeding Steppe Eagles mainly prey on small mammals, predominantly susliks, catching them by attacking from above or waiting by burrow entrances. Sometimes eagles are followed by smaller opportunistic scavengers, such as gulls or corvids, looking for a chance to steal a bit from the khan’s table.

 

It happens sometimes, however, that guests joining a feast are actually larger than the host! Steppe Eagle is quite a large bird itself, with wingspan of a female (who is larger than a male) reaching 2 metres. But look how small it appears to be (two birds on the right) when seen next to a Griffon Vulture (Gyps fulvus) (bird in flight) or a Cinereous Vulture (Aegypius monachus) (two birds in the centre), with wings of the latter spanning almost 3 metres! For comparison, an average arm span of an adult man is approximately 170 cm, so imagine how impressive these birds are when they fly! In this case, one of the Steppe Eagles has just caught a Bobak Marmot (Marmotta bobak) (probably young), however this time it is likely to give it away to stronger vultures.

 

Being excellent hunters, Steppe Eagles however do not mind to feast on a corpse of a dead horse, sheep or a Saiga antelope. This is when you can see these birds in larger groups outside migration, as otherwise they are rather solitary, each pair often occupying a very large territory. Further changes in land use in steppe areas may not only directly affect suitability of breeding habitat of this beautiful eagle, but also affect breeding performance through increased disturbance and decreased prey availability.

 

Another reason for these majestic birds to congregate during summer is steppe fire. This event offers eagles, among other birds, a unique opportunity to prey on small mammals and large insects flushed by fire or exposed to predators, deprived of the protective cover of steppe vegetation. And of course this is a rare chance to have some grilled food! Photo below shows two Steppe Eagles sharing a recently burnt patch with a flock of rare Sociable Lapwings (Vanellus gregarius). Unfortunately, in some places, increased frequency of fires caused by human activities also destroys their nests.

 

Yet another and probably largest threat to the species is illegal and uncontrolled hunting along migration routes. Some of the eagles from the Central Asian population are thought to migrate to the Middle East, with some moving all the way down to southern Africa. As they avoid crossing large extents of water, during migration large numbers often pass through narrow ‘bottlenecks’ (for example Suez, Egypt) and similar large numbers cross high mountains in particular places (area near Batumi, Georgia). Although worldwide this is not a common practice to hunt birds of prey, in some countries (such as Lebanon or Georgia) large concentrations of migrating birds, alongside with poor law enforcement, make mass slaughter of birds of prey and other large soaring birds possible. For such a long-living bird (up to 40 years in captivity!), adult mortality can do much more damage to the population than, for example, loss of several nests during their life time.

 

Steppes and semi-deserts of Kazakhstan are likely to support more than half of Steppe Eagle breeding population. And maybe it is symbolic that this bird is depicted on the country’s flag (although sometimes alternatively it is claimed to be a Golden Eagle).


 

Yes, maybe it is not the largest bird of prey, but, you have to agree, it has a look which deserves some respect!