What’s the scoop on deer movement charts based on moon phase? Do they really work?
QUESTION: I've been hunting for over 50 years and have seen a plethora of writings, discussion and videos on the use of moon phase wheels, gadgets and charts. I understand deer being creatures of habit pattern their behavior according to the moon phase, the rotation of the earth and other biological and astronomical factors. In your professional opinion, how real and effective are these gadgets? If they work, what in your opinion is the most reliable gadget? — Sgt. Frank S.
ANSWER: As a wildlife biologist, I base my professional opinion on empirical data. Researchers have studied numerous aspects of deer behavior and what might influence it, including the sun, moon, weather, temperature and barometric pressure. To date, no peer-reviewed scientific study has found any significant correlation between deer movement and moon phase or position.
As a hunter, I can be a bit more capricious. There have been several efforts, based largely on anecdotal observation, to tie deer activity to moon phase, moon position or a combination of sun and moon position or phase. And they’ve come up with some interesting stuff.
One theory postulates that the moon’s gravitational pull influences deer movement. Because it is strongest when the moon is in certain positions relative to the earth (directly overhead or underfoot), movement is greater. There’s even some scientific evidence this is true for other creatures, but we’ve yet to prove it for deer. Still, I know some hunters who swear it works.
Another theory postulates that moon phase influences timing of the rut. We know, from research, that rut timing is triggered by changes in the amount of daylight. The moon is a source of light as well, but unlike the sun, the timing of its phases vary from year to year. The theory suggests that these differences cause changes in when the rut peaks from one year to another.
Several years ago, I contacted deer biologists from all of the whitetail states and asked them when their peak rut occurs. Dates varied from state to state, and sometimes even from region to region within a state. However, each biologist stated their peak breeding dates occurred at the same time every year, regardless of moon phase differences.
Yet another theory postulates that some combination of sun (solar) and moon (lunar) factors influence deer, fish and other game movement. The resulting tables are intended to help you choose the best days and times to hunt or fish. Here again, we’re left with little hard scientific evidence to support the theory, but some folks say they work.
As hunters, we’re always looking for an edge, something that will help us better predict when deer will be more active. There are countless popular magazine articles and books suggesting when that might be. Some are based on science, and others on experience and anecdotal information. All can be useful to an extent. Ultimately, the best information will be what you observe. As a good friend of mine once said, the best time to be in the woods is when the hunting season is open.