The Constant Effort Sites (CES) scheme is the first national standardised bird ringing programme within the BTO Ringing Scheme and has been running since 1983. Ringers operate the same nets in the same locations over the same time period at regular intervals through the breeding season at 130 sites throughout Britain and Ireland; Pensthorpe operates one of only eight CES sites in Norfolk.
The Scheme provides valuable trend information on the abundance of adults and juveniles, productivity and also adult survival rates for 25 species of common songbird. The professional bird ringers arrive very early in the morning to set up mist nets to capture the birds, when caught the birds are quickly removed from the net, monitored, rung and then released.
The Norfolk Ornithologists Association has been carrying out ringing at Pensthorpe since 2006, with all of the information gathered going to a data bank at the BTO (British Trust for Ornithology) in Thetford. With their data research we have managed to track down where some of the birds seen at Pensthorpe travel to.
Constant Effort Site Ringing: PCT Actively Saving Species Flyer Spring Summer 2017