Hornet you incorrect,
Unless you have the condition to 'shoot birds' with your rifle you are in breach of the terms of your certificate, Canada Geese are NOT VERMIN they are Wildfowl and as such come under the protection of the Wildlife and Countryside act, hence the requirement to use non-toxic shot with a shotgun. I have been shooting Canadas out of season for 6 years, yes before they were on the Open General License, first 2 years with a MAFF Permit to Kill as an aid to scaring ?? Then under the OGL, I was only allowed to shoot them with .22RF and 17HMR, but a year later I got the condition for .223 Rem after quoting the 'Ruddy Duck cull'. I might tell you that I was the first person in Merseyside to be issued with such a condition for Geese, although I am certain keepers have been popping them off for years with their trusty .22 CZ's, just would not want you to land yourself in hot water due to an oversight.
FlyBoy270