That's right. Enter the Safari Zone and walk around a bit. Exit, and then Fly to Cinnibar Island, and Surf up and down the right coast of it, and you should run into Safari Zone Pokémon. Now you can run into Tauros, Scyther, Kangaskhan, Chansey, Rhydon, etc. and hurt them or catch them with an ultraball to make it easier so they can't run from you.