Monday, October 24, 2016

How to age Siberian Accentors?

Siberian Accentors at Muraviovka Park (October): top: juvenile-type, bottom: adult-type
Siberian Accentors Prunella montanella are rather common migrants at Muraviovka Park in Far East Russia. In Europe, however, they occur only as extremely rare vagrants. At least, until October 2016. Right now, there seems to be an influx of Siberian Accentors, with more records in two weeks than during the previous 100 years! You can read the full story here or here (in German).
Their occurrence in Europe fits the phenological pattern of birds ringed at Muraviovka Park, which lies at more or less the same latitude like e.g. Leipzig, Brussels or London. Most birds occur during the first half of October.
Phenology of Siberian Accentors at Muraviovka Park based on standardized bird ringing
(spring 2013,2015,2016; autumn 2011-2015)
Caused by the lack of reference material, determining the age of Siberian Accentors was not covered well in recent literature. It is widely assumed that ageing should be possible based on the criteria used for Dunnocks Prunella modularis. A very nice photo documentation for Dunnocks can be found here in the Ringer´s DigiGuide. 

Since we have ringed more than 400 Siberian Accentors within the Amur Bird Project at Muraviovka Park, we would like to share our impressions about variability and possible criteria for ageing. However, we have to highlight that we never trapped a bird of known age (e.g. a ringed re-trap) - so all the features listed below are only suggestions. We are very happy to read your comments!

three left: juvenile-type; three right: adult-type
Iris colour: juvenile-type olive-brown; adult-type warm reddish-brown

Shape of greater coverts: juvenile-type narrower, edged rufous-brown; adult-type broader, edged grey-brown

Tips of greater coverts: juvenile-type buffish or yellowish, much wider; adult-type whitish, narrower

Shape of tail feathers: juvenile-type worn, more pointed; adult-type rather fresh, broader, more rounded
three left: juvenile-type; three right: adult-type
It seems that many (most?) juveniles retained all juvenile greater coverts, while adult-type birds showed all coverts uniformly edged whitish. However, there have been individuals that did not match the pattern. Please comment - we would like to learn more!

Arend & Wieland Heim

All photo© Arend Heim

Wednesday, October 19, 2016

First record of Bewick´s Swan at Muraviovka Park

Bewick´s Swans at Muraviovka Park, October 2016 © V. A. Dugincov
Another species was added to the long list of Muraviovka Park. Local ornithologist V. A. Dugincov was lucky to spot a group of Bewick´s Swans (aka Tundra Swan Cygnus bewicki) at a lake inside the nature reserve. The family with two chicks stayed for several days. Most waterbodies are already frozen in the Amur region, while night temperatures now regularly fall below -7°C. Bewick´s Swan are breeding in the Russian Arctic and wintering in East Asia. They are listed in the Red Data books of Russia and the Amur region. The Park´s bird list now contains 298 species (or even more than 300, if you like to split some of the taxa - see under "Publications"). This is quite remarkably for an area of only 6,500 ha, highlighting again its important status for biodiversity conservation in Far East Russia.

Bewick´s Swans - a family with two chicks  © V. A. Dugincov
Wieder einmal konnte eine neue Vogelart der langen Liste des Muraviovka Parks hinzugefügt werden. V. A. Dugincov, Ornithologe aus Blagoweschtschensk, konnte eine Familie des Zwergschwans auf einem See im Schutzgebiet entdecken. Die Familie mit zwei Jungvögeln blieb für einige Tage. Die meisten Gewässer sind nun bereits zugefroren, denn die Nachttemperaturen liegen meist bei unter -7°C. Zwergschwäne brüten in der russischen Arktis und überwintern in Ostasien. Er wird auf den Roten Listen Russlands und des Amurgebietes geführt. Insgesamt konnten nun bereits 298 Vogelarten im Muraviovka Park nachgewiesen werden (oder mehr als 300, je nach Taxonomie - siehe "Publications"). Das ist beachtlich für ein Gebiet von nur 6.500 ha, und zeigt erneut, wie wichtig der Park für den Erhalt der Biodiversität in Fern Ost Russland ist.

//Wieland