How do you properly play/build as Tank Junglers vs AP comps?

I recently picked Udyr and Gragas up and tested out 2g's build. For the first 5 games his build was pretty great, but on the 6th game, when I encountered a heavy AP comp, everything went downhill. Is this why many argue that devour is better on Udyr still? As a tank jungler what runes should I be taking? I've been using AS reds, Scaling Armor Yellows, Scaling CDR blues, and movespeed quints. Perhaps I should be taking scaling magic resist instead and flat armor? Also what should I try to build first vs AP comps, spirit visage maybe?