The greater spotted eagle (Clanga clanga), also called the spotted eagle, is a large migratory bird of prey belonging to the family Accipitridae. It is a member of the subfamily Aquilinae, also known as booted eagles. It was once thought to be a member of the genus Aquila, but was reclassified to a distinct genus, Clanga, along with the two other species of spotted eagle.
During the breeding season, greater spotted eagles are widely distributed across Eastern Europe, parts of Central Europe, central Russia, Central Asia, parts of China, as well as some other isolated areas. During winter, they migrate primarily to South Asia, Southeast Asia, the Middle East, the upper Mediterranean Basin and parts of East Africa. Greater spotted eagles favor wetter habitats than most other booted eagles, preferring riparian zones as well as bogs, lakes, ponds, and other bodies of water surrounded by woodland or forested land. They breed primarily on floodplains, especially ones that experience high water levels. During winter and migration, they often seek out similar wetland habitats, but have also been observed in dry upland areas such as savanna plateaus.
The eagle is an opportunistic foragerespecially during the winterand will readily scavenge a variety of easy food sources, including carrion. Greater spotted eagles eat small mammals (principally rodents), frogs, and a variety of smaller birds, especially vulnerable water birds. It occasionally feeds on reptiles and insects. The eagles are primarily aerial hunters, gliding from concealed perches over marshes or wet fields to catch prey. This species builds stick nests in large trees, laying a clutch of one to three eggs. The female of a pair incubates and broods the young while the male hunts and delivers prey. Parents rarely raise more than one fledgling per year. As is common among birds of prey, the oldest sibling is much larger than its younger siblings, and the oldest sibling often attacks and kills the younger siblings.
This species' range overlaps broadly with the closely related lesser spotted eagle (Clanga pomarina). The two species are now known to hybridize frequently, to the detriment of populations of the rarer greater spotted eagles. The greater spotted eagle is classified as a vulnerable species by the IUCN. Its populations are threatened by habitat destruction, collisions with objects, and hybridization with lesser spotted eagles.
Taxonomy and etymology
Greater spotted eagles are members of the subfamily Aquilinae, or the booted eagles, a monophyletic group within the larger Accipitridae family. All booted eagles have feathers covering their legs. Members of this diverse, wide-ranging family may be found on every continent except Antarctica. Thirty-eight species of booted eagle are recognized.
Booted eagles are often grouped with the genera Buteo and Haliaaetus, and other more heavy-set Accipitridae, but they may be more closely related to the more slender accipitrine hawks than previously believed. The greater spotted eagle's closest living relative is the lesser spotted eagle; they seem to have diverged from their most recent common ancestor around the middle Pliocene, perhaps 3.6 million years ago (mya). This "proto-spotted eagle" probably lived in the general region of Afghanistan, and split into northern and southern lineages when both glaciers and deserts advanced in Central Asia as the last ice age began. The northern lineage subsequently separated into the greater (eastern) and lesser (western) spotted eagle species of today, probably around the Pliocene-Pleistocene boundary almost 2 mya.
The spotted eagles were long classified as part of the genus Aquila, along with several other mostly large, brownish eagles. However, molecular phylogenetic studies using DNA sequences of one mitochondrial and two nuclear genes showed that the spotted eagles form a monophyletic group with each other and the long-crested eagle (Lophaetus occipitalis). Studies suggest that the spotted eagles should be grouped with Lophaetus, or that all of these species should be grouped within Aquila. Furthermore, a close relationship has been found between the spotted eagles and the black eagle (Ictinaetus malaiensis) native to Asia. The spotted eagles, long-crested eagle and black eagle may comprise a species complex or clade. The spotted eagles were ultimately reclassified as a distinct genus, Clanga, due to overwhelming genetic evidence and large divergences in morphology and ecology between spotted eagles and their sister taxa.