Glossy ibis (Plegadis falcinellus) tend to wander. I can see them in large numbers at home, in western India, where there is a resident population. But they often fly to Africa or eastern India in winter. Those are the short distance travellers. A west African population seems to have made its own way to South America in modern historical times, and then spread into northern America. In Europe they are reported all the way north in Norway and Iceland. In New Zealand there are sightings as far south as Dunedin. However there is also a history of local extinctions followed by recolonization. Only north Asia and most of South America seem to be totally free of sightings till now.
I got close enough to one in Mangalajodi in Odisha to take the portrait that you see above. The sun was positioned just right to get that glint of green off the fluorescent nanostructures on its wings. So much of a bird’s colours are due to pigments that we forget that a large part is also due to various kinds of nanostructures which are designed to diffract light. You just need to see the shimmery blue in a magpie’s coat to see that even the commonest of birds use them.