Ohh Jonothan this is where i can get you!
a flock pigeon is the same as the cresed pigeon that is sometime called a topknot, thats is the real Top knot there!
actually flock pigeons, crested pigeons and topknot pigeons are three separate species (although the names may colloquially be used for one another). The one in the photo above is the topknot pigeon.
