We're in the uk and have four rescue swans (two angel wing, one severe arthritis and one brain damaged) we've been told that if we're going to lose any over winter it'll be the arthritic one. We have a lake with an island and two ponds for shelter already but wondering if its worth building a protected shelter to try and help as much as possible? We know swans aren't keen on shelter but don't want to end up with a dead one if it would have helped! Thank you! X