On the islands hidden lake there’s always a few of them. Not only are their eggs good food but every now and then they’ll give you a golden egg. Perfect for leveling if you plant a base at hidden lake. Not to mention they keep that lake clear of piranhas for you! Don’t need to tame just grab the eggs
These ducks spawn in small lakes or pond size bodies of water . I always find two or three in the lake that connects with the swamp on the southside of the map closest to the red avilus . Also beware of titanboa coming from hills and sarcos going into water . I suggest you take a bird and keep a close eye .