Well i'm not 100% sure about the defence, but train range at rock crabs or experiments until about 50-ish, and then do Biohazard and train at ogres until 80 I guess. At 70 I switched to blue dragons as they are slightly less boring. Plus you get quite alot of clues, which are fun to do when your bored. They are level 3 also.
If you wanted to have the same range as def, use longrange. That would take ages though >.<