I didn't go very far into the marsh as I didn't want to rattle them. After having watched them drop down from a high altitude and land together one could only assume they were migrating. The analogy of a bunch of serious cyclists pausing at a rest area came to mind. I figured the birds deserved to rest so I didn't try to get close for better photos for fear of putting them up prematurely. These are all at full zoom (300mm).