Thursday, April 25, 2013

Long-distance Clara

Female Whitethroat

Here's a bird with a little story to tell. This morning I caught a Whitethroat already wearing a ring (a 'control'). The number looked kind of familiar to me so I asked a few other local ringers if it was 'theirs'. It turned out to have been ringed near Tempsford in Bedfordshire, as a chick in the nest, back in June 2010!

When this information is crunched by the BTO, it'll say that the distance travelled between its nest and my place is only about 6km over slightly less than three years.

But in reality, it'll have made the journey from Bedfordshire to sub-Saharan Africa once in autumn 2010, then back the other way in spring 2011 and back again, probably the same in 2012 and has made it back again in 2013. So that's six journeys so far. Each time, it has to fatten up before leaving the UK, make its way through western Europe and through north Africa. For argument's sake, let's say it spends winter in the sahel in Senegal.

If it flew in a straight line directly there (which of course it won't have), that would be a journey of more than 2,700 miles each time. Multiplied by six, that's 16,200 miles! 26,000km!

The oldest known ringed Whitethroat was nearly seven years old, so this one has a way to go to beat that...