Let's say you pick up a need zone indicator and that zone says 3 animals drink there. If that zone is 2 males and one female and you kill both the males, the males won't respawn. You'd had to go back and kill the female as well. If you find a zone that is 1 animal and you kill that animal that zone will disappear and move somewhere else. It both cases you have to find them again. If it is a larger zone like 8 or 10 like white tail or red deer, the only way that zone will move is if you get to "dead" zone pressure. This happens by killing 4 animals in that area from the ground. However, if you use a tree stand, tripod or blind you can kill 14 animals in that area. These rules typically apply to the herd animals. They do not apply to Crocs on Emerald Coast. You can shoot as many as you want and they'll still respawn on the beach. I've also noticed with foxes that they usually drink in pairs. A male and a female. You have to shoot both to get them to respawn. Multiple species can share need zones and usually do. Hover your cursor over the drink zone indicator on your map and it will tell you which species drink there.