RSB only listed two other factors , severe winters and a poor mast crop. Severe winters and a poor mast crop will occur periodically whether there are 8 DPSM or 15 DPSM. Under the same conditions the PS deer density will be higher with 15 OWDPSM than with a herd with only 8 OWD PSM. The effects of predation and non-hunting mortality increase with low deer densities so once again RSB was just blowing smoke.