Circaetus gallicus in4mational navigator

ST Eagle nesting in central southern Switzerland

Dec 17, 2017 / Comment

The next recently published article is dedicated to tracking a breeding attempt of Short-toed Eagles in the Canton of Ticino /map/:

• Filippo RAMPAZZI, Luca PAGANO, 2017 – La nidificazione del biancone Circaetus gallicus nel Cantone Ticino (Svizzera) [Nesting of Short-toed Eagle in the Canton of Ticino (Switzerland)] // Bollettino della Società ticinese di scienze naturali, 105: 77-85. – Short-toed Eagle. file (It) {rough translation}.

The record of successful breeding after the long absence of such data for central southern Switzerland can be considered as an evidence of Short-toed Eagle spread in Switzerland and northern Italy in recent years.

Our sincere thanks to Luca Pagano for kind sharing the paper!

 

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