08 April 2011

Ringing in numbers

Things are getting very exciting here in the Demography team as most, if not all, of the ringing data are computerised for 2010. We can now start analysing the information and try to understand why we ringed over a million birds last year!

As we had a great breeding season last year, you would think that the number of juvenile birds and those ringed as chicks would provide a large chunk of the ringing totals. Looking at the Pie Chart below shows this is the case.

So 66% of birds ringed in 2010 hatched in the year. The 3% of unaged birds would largely be down to birds that do a complete post juvenile moult, a couple of months or so after hatching, so they will have adult plumage and can not be aged as an adult or juvenile reliably.

To compare with 2009 the Pie Chart below shows the percentage of birds ringed for that year. As you can see there is not a massive difference but 2009 was also another record year for the number of birds ringed.

The bar chart below shows the number of chicks ringed for the past 6 years. Fingers crossed for another good year and success in nest recording.

Thanks to Richard Vaughan for the photo in the bar chart and apologies for the overload of graphs in one blog post.

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