John heads back to France26 Jul 2012
John has continued his migration in idiosyncratic style! Having been just southwest of the Jura last Friday (20 July), by Sunday 22 July he was in Catalonia, so becoming the fourth of our tracked Cuckoos (after Clement, Lyster and Reacher) to take a south-westerly route into Spain. His tag transmitted for longer than the planned ‘ON’ period so we were able to follow what happened next - and that evening he moved off west, ending up 120km (75 miles) WNW of here, on wooded slopes in the Pyrenees close to the French border, by the next morning. As if this wasn’t strange enough, locations received on Wednesday 25 July showed he had continued along this trajectory, had crossed the Pyrenees completely and was just inside Landes region of southern France, a few kms ENE of Bayonne.
This movement appears very unusual, both because of the 90 degree change in direction to NW and because he has re-crossed an apparent barrier (the Pyrenees) at an oblique angle. There doesn’t appear to have been any unusual weather etc in the area when he arrived in Catalonia so it’s not clear why John has behaved like this. Where will he go next?
What effect might annual releases of non-native gamebirds be having on native biodiversity?
Henrietta Pringle reveals the work behind a recent paper on gamebirds and predation
Climate change in a warming world
BTO science contributes to our understanding of future scenarios, and informing policies and conservation management strategies to help species adapt.