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The summary

Short-toed Snake Eagles have the rich social language, various tools which help them to express their intentions and relation to behaviour of other representatives of their species. The main problem of studying their behavioural language is defined by difficulties of correct interpretations. Besides various vocal signals, these eagles reveal a rich body language vocabulary, thanks to the extraordinary plasticity of their plumage, which is used for hovering in different airflows while hunting. Simplistically, 3 types of signals are identified: those related to movements, postures and holding of plumage.

› Examples of the gestural communication are: aggressive demonstratively slow and strong wing-beats, so-called «vulture» flights, territorial «festoon» display flights.

› Communicating through postures includes: an aggressive «albatross» posture, a posture of «angel» which is used for marking a chosen nest for the partner.

› Communicating through appearance changes at close contacts comprises states of occipital feathers and pupil size, which can express both tension and relaxation of birds.

This brief review is nothing more than an invitation to observe and puzzle out those various and subtle means of ST Eagles’ communication.

Moments of life

During these 20 years, while we have been following the Short-toed Eagles, we could obtain numerous pictures taken in ideal conditions, some of which we later published, however, I never played with the thought seriously that I should take advantage of it since photography is very laborious and has little use in conservation.

Nevertheless, in 2010, I decided that I would give it a try at a nest site where I could do it without any disturbance. In January, I built a hide, which I dug in the ground about twenty metres from the nest. I made a frame of beech and covered it with smaller pine branches. This nest site seemed to attract this particular pair, they visited it during last autumn several times.

I made myself comfortable in the hide in the first days of March, not knowing how remarkable moments and wonderful events of the everyday life I would experience soon.

I used a quite mediocre Nikon camera with 110 mm equivalent focus length*, but still I could record their whole breeding cycle except incubation without being noticed by them.

I would like to share a few pictures…

Bernard Joubert

* – also, photos taken with Panasonic Lumix FZ1000 are included.

The previously described article is currently available to download:

• Ugo MELLONE, Giuseppe LUCIA, Egidio MALLÌA, Vicente URIOS, 2016 – Individual variation in orientation promotes a 3000-km latitudinal change in wintering grounds in a long-distance migratory raptor // Ibis. Accepted Author Manuscript. doi:10.1111/ibi.12401 – (En).