masdog
What is the airspeed of an unladen Swellow?
But its not a fish. It’s a dragon with a secondary water typing. It may look like a fish, but that doesn’t mean it is a fish.Well, that's game logic. In the anime, it's different as fish Pokemon can only really be used in the water, otherwise they're just about as useful as Misty's Goldeen.
And every fish in the game is restricted to water. You can’t catch Magicarp or the other fish unless you’re in or right next to the water. Tatsugiri spawns on land and in the water.