As fall draws ever closer, all the squirrels (chipmunks, greys, reds and groundhogs) are becoming much more noticeable, storing up fat if they hibernate (groundhogs), or food to see them through the winter (the rest). Chipmunks head underground once winter sets in. They maintain a separate storeroom of food to which they will go periodically through the winter, from their cosy sleeping quarters. Thus, they are not true hibernators as groundhogs are. The reds and the greys will remain active throughout the winter except on the coldest of days.