Bad news? There is a full moon on Nov. 12; this will flood with moonlight the opening week nights of muzzleload deer season (opening Nov. 9). Everybody knows that the deer will feed all night and hole up all day, frustrating hunters. Everybody knows this. Except that it is not true.
A recent study by Penn State University monitored movement of female adult whitetails fitted with GPS tracking collars during the month of October for several years. These were wild, free-range deer on public forests. During full moon nights they moved less than on nights when the moon was dark (a new moon). Again, under the full moon deer moved less, not more. But the difference in movement amounted to an average of just six meters per hour.
More significant was when deer moved. They averaged about 60 meters of movement per hour until about 6 a.m., when movement spiked quickly to peak at about 125 meters per hour at roughly 7 a.m. It then declined to 45 meters per hour at 10 a.m. Evening activity showed a similar spike starting at about 3 p.m., peaking at about 6:30 p.m. and dropping sharply toward minimal movement at about 8 p.m. New moon, partial moon, full moon. It didn’t matter.
This makes perfect sense when you think about whitetail physiology. Deer are ruminants; they have more than one stomach. It takes them from one to four hours to fill up the first stomach, depending on forage abundance. Their maximum movement will be while transitioning from bedding cover to feeding grounds and back again.
After filling their rumens (first stomach) they bed and ruminate, i.e. regurgitate and re-chew what they took in. This process takes about four to six hours with, perhaps, some stretching and nibbling every few hours. Soon after, feeling hungry again, the deer travel back to a major feeding site. Like clockwork this cycle moves through the days, months, and years.
Deer movement is largely determined by their digestive systems coupled with their preferred initial foraging times, dusk and dawn. Moonlight or no moonlight, deer movement is slave to deer digestion; there is no way they can “feed all night”. So, continue to expect dusk and dawn deer activity. [Thanks to Ron Spomer, www.ronspomeroutdoors.com, of Sporting Classics for this revelation.]