Second calendar year fulvescens Greater Spotted Eagle,

Basai, Haryana; 19 to 30 April 2003.

Mike Prince

 
A pale eagle was initially reported from Basai on 19 April 2003 by Aaditya and Debashish Chakravarti. They described it: "back and head were almost completely a dirty white with very dark brownish black primaries which, from its distant position on a stump in the marsh gave it the appearance of a large Neophron [Egyptian] Vulture. It flew briefly revealing buff-grey coverts and underbody and dark flight feathers. The wing edges were parallel with a shortish tail." These views led them to think it might be a bleached Tawny Eagle.

On the evening of 27 April I saw what was obviously the same bird. It was a large but small-headed eagle, with a longish bill and shaggy, almost vulture-like, nape. Obviously very worn, it was not even obvious what genus it was since it looked superficially like a Changeable Hawk Eagle or even an immature Crested Serpent Eagle. However, the proportions of wings and tail, the baggy, feathered legs and strong bill were indicative of an aquila.

The flight feathers and tail were dark brown, and very worn. Upperwing coverts were mid brown, median coverts and scapulars showing white and pale buff. The underparts were all white/creamy buff. The head was a gingery-pale buff, with distinctive blackish lores encircling the eye. The gape line extended back to level with the centre of the eye and the nostril appeared to be slightly oval-shaped.

Thanks to several people who commented on this bird, in particular Dick Forsman who was the only one to confidently identify it as a fulvescens Greater Spotted Eagle first time around! Quotes such as "amazing bird", "interesting bird", "very tricky" were received! Opinions were generally divided between Tawny (or possibly Steppe) and Greater Spotted, with some of the identification features mentioned being:

  • uniformly worn upperwing coverts and secondaries age it as a second calendar year.
  • legs not as fully feathered as Tawny, tapered trouser shape suggests Greater Spotted; tarsi feathering rather short.
  • odd head shape and apparent crest maybe a result of ragging by crows or drongos, or even other eagles. Prominent but not regular enough for a true crest.
  • bill size and shaggy nape smacks more of Greater Spotted
  • not yet moulting, is very worn; very worn juvenile plumage is what you'd expect at this time of year
  • Greater Spotted: dark face and structure of legs help to exclude other pale eagles
  • flight views would help: Tawnies often show pale wedges on the inner primaries in flight and usually show a broad pale lower back extending to the rump, which is good supporting evidence, not usually shown by Steppe.
  • gape ends under eye, i.e. too short for Steppe
  • shape of nostril is diagnostic - circular in this bird means it is one of the "spotted" eagles and not a Tawny or Steppe.

It was interesting to note different views on the nostril shape, i.e. some thought it to be circular and some oval! Bill and I had difficulty seeing the shape in the field, and it is only really in the two enlarged photos that it can be seen reasonably clearly. Even in one of these it does not look perfectly round, although I think this is an effect of the cere appearing to slightly overlap the nostril hole. Certainly the nostril is not the obvious elongated shape shown on the Steppe Eagle photo.

Most people did think it was a Tawny Eagle, although the combination of features mentioned confirm it to be a second calendar year Greater Spotted Eagle of the pale fulvescens form. A particular interesting discussion, and a good example of concentrating on finer points of structure for identification rather than being swayed by plumage colouration.

Mike Prince, July 2003.