A brief evening visit to Castle Mill (20/04/10) revealed a ring on one of the two resident Oystercatchers! See the previous post for a photograph of these birds. This bird was most likely ringed locally several years ago.
The species can be quite long lived - the British longevity record for a ringed Oystercatcher is 36 years and 8 months held by the Wash Wader Ringing Group. They believe that this record could easily be extended.