Pintail type hybrid?

Sort these two out please, both at Keptie Pond and neither bothered about people. I reckon I might be able to hand feed the first one! When I arrived I thought woohoo a Pintail, then later it climbed out of the pond with tame Mallards, clearly something not right! I've since found out the "Pintail" had a neck ring when it was seen last week, it must have fallen off or a concerned person could have captured it and removed it?

This one's a puzzle, lots of Pintail drake, a bit of a of a Mallard bib which on other photos reaches on to the breast, and the yellow legs of a Gadwall. Also, it was near to but not attached to the other odd one below, looks like someone's collection has escaped

This one looks to be a Gadwall in eclipse, although I'm not to sure about the head.  Comments welcome, I've got other things to do at the moment, although I've found some similar hybrids online

Herring Gull T:524 at Whiting Ness

House Sparrow on a sunk at Gourdon Harbour. No white gulls though

Linnet at Whiting Ness, Arbroath

Carrion Crow also at Whiting Ness, just before sunset