Purple martins

Wednesday noon, after a boat trip on the Environaut, we listened to a presentation by Bob Aeppli.
He told us a lot of interesting facts about purple martins.
We learned that the purple martin, which is the largest North American swallow, has its name by the coat of the male martins, which gleams purple in the sunlight. The female birds have a black or dark-gray coat and a white front.
Bob Aeppli told us also that these birds prepare to be close to humans; they do not like to live in the woods. Also he reported that he has built special nests, to patronize the squabs, which could be attacked by other birds.
The purple martins eat insects, like dragonflies.
After this presentation we were able to watch the birds close by using binoculars.
This was really interesting.
But the best part was, when he showed us the young (baby) birds and ringed five of them!!!