The article is not about carrier pigeons, but about the passenger pigeon. This is a North American species of pigeon famous for the huge size of its flocks, lar

The article is not about carrier pigeons, but about the passenger pigeon. This is a North American species of pigeon famous for the huge size of its flocks, large enough to darken the skies on a sunny day. It was commercially overhunted to extinction by the early 20th century, a famous example of extinction.