I've caught a Squirtle (starter), a Weedle, a Poliwag, a Magikarp (it takes 500 candies to evolve), a Pidgey, a Rattata, a Paras, and a Drowzee. I live near river, so I imagine when I leave the house I'll catch a few more water types. Unfortunately the local gym was taken over by a Jolteon lol.