An email from Roger Peart of Dorset...
to Jon Turner’s question about Canada Geese with blue rings he could try looking
on http://www.cr-birding.be/cr-Canada%20Goose.htm which is on
the site coordinating European colour ringing.There are
at least a couple of projects using blue rings on CANGO :- Richard de
Hearn, W&WT, Slimbridge