#1 is a White Ibis, as has been noted, #2 is a duck of some sort, not sure about the Muscovy duck, hard to tell without seeing the head properly (any more pics of this one?), #3 is just too dark to tell, #4, not sure of this one, but I don't believe it is a cowbird, unless this is some form of mating or juvenile plumage, #5 is a tern, most likely an adult Royal Tern in non-breeding plumage, alternatively, it could be an Elegant Tern in non-breeding plumage - I would need to see a better shot with the beak and back of the bird to really tie it down. Sorry I cannot help you any better than that.
WesternGuy