Yes, mallard ducklings dive under water to evade predators (or what they perceive as predators) and, more rarely, to reach food that they can not reach from the surface. Adult mallards also dive under water, but only very rarely. You can see video of this at www.hikingwithchuck.com/Downloads/DownloadVideos.htm
they can.
get a water Pokemon yhe TM dive and well dive under the water
you dive under water
in the under water use dive
you dive for it and get it under water
12-15 minutes
you cant go underground but you can go under water by using the move dive. you get dive in mossdeep city
get the HM dive and dive down and you'll find a cave entrance
Submarines dive by opening vent valves that allow sea water to push air out of their ballast tanks.
The feathers are heavily oiled to repel water.
they do not get crush because they are very strong and they can breath under water
you swim out to the spot where sootpolis is and you dive under water and go around that area until you see a spot with like a cave door and you go in. then you dive up and surf the water until you reach land.