Ringed Goldfinch ??? (1 Viewer)

Can anyone tell me why this bird has been ringed?

http://www.youtube.com/watch?v=bzMX6l9r_DQ

Keep watching and you can clearly see the ring.

Thanks

it will be ringed to study its longevity and movements to help further understand and protect wild birds. About 1% of birds caught and ringed are recaptured or found dead allowing for information to be learnt about the birds. I currently take part in a constant effort scheme where we ring in the same place across the breeding season measuring productivity and breeding populations. We also have birds returning after migrating to Africa, in some cases more than once.

This should give you a better idea.