To answer this question, I referred to Dr. James Kroll and Ben Koerth’s book entitled, Solving the Mystery of Deer Movements. The authors state, “The lowest amount of daytime activity occurs during the full moon, while the new moon has the greatest amount of daytime feeding.” Their trail camera study indicated the following percentages of activity per moon phase for both bucks and does: New Moon (33.7 percent), First Quarter (26.1 percent), Full Moon (19.9 percent) and Last Quarter (33.5 percent). The authors concluded, statistically speaking, “Moon phase does not appear to predictably affect deer activity. Because the moon is such a noticeable phenomenon in our world it seems almost intuitive it must have equally profound effects on the habits and lifestyles of animals as well, at least we all want to believe it to be so.”
Years ago, Dr. Mickey Hellickson, chief wildlife biologist of the 825,000 acre King Ranch in south Texas collected over 420,000 observations on 43 collared bucks. Hellickson found, “Although the moon may influence buck movements in other ways, his data did not indicate any patterns relative to the effects of moon phase on buck movements.”
Hellickson then looked at only the daytime movements (6:00 a.m. – 7:00 p.m.) of bucks during the October to January time frames for two years. He then compared these daytime movements to data centered on a full moon against a new moon. For Year 1, Hellickson found that bucks moved an average of 58.9 percent of the daytime hours during a new moon, while 52.2 percent during a full moon. In Year 2, bucks moved 36.1 percent during a new moon and 36.7 percent during a full moon. Obviously, none of these buck movements were vastly different. Thus, during the hunting season, daytime buck movements do not appear to favor one moon phase over the other.
Most hunters would swear that temperature, relative humidity, or barometric pressure have an affect on buck movements. But, Hellickson’s data proved otherwise. In fact, none of the correlations with buck movements and weather parameters were even close and remember, this was based on a data set of over 420,000 buck observations.
A classic study conducted by Paul Beier and Dale McCullough entitled, “Factors Influencing White-tailed Deer Activity Patterns and Habitat Use”, was conducted at the George Reserve in Michigan. The authors looked at the effect of temperatures, wind speed, cloud cover, relative humidity, fog, rain/snow and moonlight. None of these weather parameters were proven to be significant in relationship to deer movements.
Although barometric pressure was not included in Beier and McCullough study and Hellickson found it was not significant, other researchers have found a rapidly falling barometer (associated with storm events) can have significant effect on daytime deer activity. When hurricanes, Isabella and Ivan hit the East coast a few years ago, I saw numerous mature bucks during the day that I never knew existed. If there’s one weather parameter that most likely affects deer movements, it’s significant changes in barometric pressure.
Conclusion: Research by Hellickson (and others) shows your odds are not better whether you are hunting during a full or new moon. Although biologists and hunters are always trying to piece together buck movements in relationship to moon phase and weather parameters, no data has been found to completely solve the puzzle.
Does moon phase and/or weather affect buck movements during daylight hours? The answer is primarily no, but it all depends. As for moon phase, data suggests all the phases are basically the same in relation to deer activity with no significant differences. Weather parameters seem to be site specific. I’ve seen data that show drastic changes in barometric pressure do affect deer movements. Although writers may claim moon phase and specific weather parameters have an effect (or no effect) on deer activity, no biologist has data or the magic pill to accurately predicting deer movements. The bottom line is this there are too many variables to consistently sort out deer activity in relationship to moon phase and weather parameters. And that’s why we call it hunting.
Obviously, buck-to-doe ratios, a herd’s age structure, general condition of the buck, does and fawns, genetics, predation and hunting pressure all play a role in movement and activity patterns. If the moon parameters work for you, then by all means, use them. One must remember that all full or new moons are not created equal, from month to month or from year to year. One month the moon could be 17 degrees off the earth’s horizon and 118,000 miles away, while next month it could be 78 degrees and 210,000 miles away. Do these moons have differing effects? Who knows? The bottom line is you’ll never experience deer movement unless you’re in the woods. In other words, just hunt!
