Spring is coming, adult birds are almost all back!

Of 44 tagged adults with well working transmitters, 41 are in (back) in Switzerland. The other three are actively migrating towards the North-East in France.

Of the 2015, 16 and 17 young-adults, immatures and juveniles only single birds are on the move, most of them doesn't seem to be in any hurry or urge to move northwards.

Some movements of February 2018, red are adult birds, yellow 2017 juveniles and green 2016 immatures.



A closer view on the last part of the migration before coming back into the breeding/natal area. I assume that the adults that migrated this month, are younger individuals eversince they are the last ones to come back into their territories.



Some birds miss the right exit. Almost all birds travel north of the lake of Geneva, heading already North-East since France/Spain. Some seems to miss the exit towards the study area where they are once tagged. The two birds that flew in the direction of Basel before going back North form a breeding pair. The other red line, the adult that went in the direction of Zurich is kiws39, one of the first birds that left the country, see blog of November 9th 2017! 

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