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Bernard Joubert’s article on communication of ST Eagles

Dec 10, 2017 / Comment

Photos taken by Bernard Joubert: Short-toed Eagles' communication posturesThe following paper by Bernard Joubert on Short-toed Snake Eagle communication abilities was recently published:

• Bernard JOUBERT, 2017 – Circaète Jean-le-Blanc : des "mots" pour le dire [Short-toed Eagle: "words" to tell] // Rapaces de France, n° 19: pp. 54-55. – Short-toed Eagle. file (Fr) {rough translation}.

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.

 

Another subspecies of Short-toed Eagle determined

Nov 30, 2017 / Comment

Quite many articles dedicated to Short-toed Eagle are reprsented on the ResearchGate and not yet described on our site. Currently, we’d like to mark one, which is very fresh, raising a topic of georgaphic variations at the farthest border of the species range /map/ and questioning again the concept of Circaetus gallicus as a monotypic species:

Shengrong Nathaniel NG, Les CHRISTIDIS, Jerry OLSEN, Janette NORMAN, Frank E. RHEINDT, 2017 – A new subspecies of Short-toed Snake-eagle from Wallacea determined from morphological and DNA comparison // Zootaxa, Vol. 4358, No. 2: pp. 365–374. (En).

The abstract of the paper available now is of great interest itself.

 

GPS-GSM tagging of Short-toed Eagles in Hungary

Oct 14, 2017 / Comment

Within the framework of the Turjánvidék LIFE project, which aims the preservation of habitats of such species as the endangered Hungarian Meadow Viper (Vipera ursinii rakosiensis), two Ecotone GPS-GSM trackers were bought in 2016. The main aim was to follow the life of a Short-toed Eagle pair residing close to and hunting regularly on viper habitats. Since the capture of the adult male failed in 2017, experts marked the offspringÖrs on SATELLITETRACKING.EU of this pair with the transmitter /map/. The chick was named Örs, an ancient Hungarian name meaning «human», «man» or «hero» but also a name of a Hungarian tribe from ancient times.

Örs left the natal area on October 1st and its tracks can be followed on SATELLITETRACKING.EU.

The other transmitter was deployed on a repatriated individual in 2016, which died two months later in Poland. Its tracks are not available on the aforementioned website yet, however, another post will appear here if so.

Gábor Papp

 

Short-toed Eagle breeding biology in NW India

Aug 31, 2017 / Comment

Ritualised behaviour between the female and male Short-toed Snake Eagle / by D. MoriAn article about breeding of Short-toed Eagles in Surendranagar District /map/ has been published in the Indian BIRDS – Journal of South Asian Ornithology this year. Such releases are always of great interest because observation data on Indian Short-toed Eagles are rarely available on the Web:

• Devvratsinh MORI, Raju VYAS & Kartik UPADHYAY, 2017 – Breeding biology of the Short-toed Snake Eagle Circaetus gallicus // Indian BIRDS. Vol. 12, No. 6: pp. 149-156. – Short-toed Eagle. file (En).

 

Photos of Short-toed Eagles in Northern Ukraine in 2017

Jun 30, 2017 / Comment

PISMENNYI K. 2017. Northern UkraineCompiling of the next annual gallery has been started, the gallery of photos taken in different regions of Northern Ukraine this year. Each Short-toed Eagle identified individually is indicated, as always, in captions by a letter and a year of the first representation in photo galleries on the site. The collection will be updated after the season.

 

Breeding biology & interactions of STE & LLB in Israel

May 30, 2017 / Comment

The recently accepted article of Guilad Friedemann and others is a result of the study of interspecific interactions between Short-toed Eagles and Long-legged Buzzards and their breeding in the Judean Slopes /map/:

• Guilad FRIEDEMANN, Yossi LESHEM, Lior KEREM, Avi BAR-MASSADA & Ido IZHAKI, 2017 – Nest-site characteristics, breeding success and competitive interactions between two recently sympatric apex predators // Ibis. Accepted Author Manuscript. doi:10.1111/ibi.12498; the Supplementary online material – Short-toed Eagle. file (En).