Friday, September 21, 2012

100 000 + !!!

The pheonological clock of songbirds is ticking quicker and quicker as autumn approaching. During the last days every new day has doubled the numbers of migrating finches. Today it was happened again and already up to very remarkable level.

About hour after sunrise this happened – the mass movement of finches. Despite fairly strong (8-10 m/s) wind, it south-westerly direction was right and instincts of wild birds has been triggered. Due to strong wind, birds flew very low over the ground and have been very well observable. It was unforgettable experience to witness the almost constant flow of songbirds flying toward sea. Big part of the flocks has flew in the shelter of the last trees till the end of the southern tip and then turned to the south-west and taking some altitude. Most of the departing flocks were not able to rise higher than 200 m, but our vertical radar has revealed some small groups returning in high altitude of some 300-400m and with huge speed due to tailwind.

The biggest numbers of migrants had Chaffinch / metsvint Fringilla colelebs – 86 170. Unidentified small songbirds has been counted 15 090 and 9160 individuals of Siskin / siiskike Carduelis spinus recorded. Also the White Wagtail / linavästrik Motacilla alba had very good migration – 597 birds has been counted. In sum, over 106 000 passerines has been counted today, which is one of the best numbers for the Pärnu county and confirm the migration hotspot status of the Kihnu. Among raptors, 147 Sparrowhawks / raudkull Accipiter nisus passed today and also 8 Kestrels / tuuletallaja Falco tinnunculus, 6 Merlins / väikepistrik Falco columbarius.  

In the late afternoon the wind was calming down and the last day of summer has showed off his mild side. We have installed first time in Estonia the dedicated equipment for monitoring and recording night migrators vocalizations by Wildlife Acoustics. And now, our radar screen shows again the south westerly massive migration of songbirds, which remains otherwise invisible for the human eye. Hopefully the sound recordings can give us data on the species composition of the night migration. 

There are the finches flying? (Blue Tit)

Landscape with myriads of migrating songbirds
The Siskins migrate in dense groups and are the best flyers among finches

The juvenile Merlin 
The song meter recording device (right) and special night flight call recording microphone set, mounted on the plastic plate for improving a distant flight calls pickup.

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