Would appreciate expert opinion/verification. These pigeons were very large (approx 40cm), predominantly white. Significantly larger than a regular pigeon/dove. Not seen them in my area before. Counted at least 17 in a video I took. Believe it may be a type of Imperial Pigeon. If so, far out of area but may just have been passing through? Imperials are known to be migratory and the weather here at the time was very hot (40s plus).