I ended up making 20 keepers on one work zone which has 1 habitat, 3 keepers huts and 2 big staff rooms (all properly powered)... then after all the animals were still dying from hunger i looked and realized all 20 keepers were going to the habitat entrance (not entering it) and back to the keepers hut (not entering it) and back and forth over and over again never actually going into the habitat to fix anything... There were occasionally some keepers going in that weren't attached to any work zones which doesn't make any sense to me.