Maine Outdoor Journal

The white-tailed deer is the most-pursued big game animal in the world. As a result, it is also probably the most studied, by both scientist and sportsman alike – and the two are often one and the same.

Despite this, there's probably as much misinformation circulated as there is good information. Sorting through it and finding the truth about whitetails can be as challenging as hunting them.

So-called whitetail experts are often quick to tout the latest theory. Sometimes it's based on sound science, other times mere anecdotal observation.

Take the moon, for example. Theories abound on how the moon's position or phase affect deer activity, especially rutting behavior. One camp claims the moon's position has a direct influence on deer activity levels, with peaks occurring when the moon is directly overhead.

I have a friend who has tested it for several years and swears by this technique. I experimented with it for a couple of seasons with no recognizable results.

However, my friend hunts in Connecticut, where you would pretty much expect to see deer moving just about every time you hunt. I hunt in Maine, where seeing any deer movement is the exception rather than the rule. Conclusion: insufficient data.

Another camp favors a theory that the moon phase influences timing of the rut, with autumnal full moons – the timing of which vary from year to year – being the trigger for rutting and breeding behavior. Their hypothesis is based on sound scientific principles, and backed up with considerable anecdotal observation. I have another friend who backs it unequivocally.

Again, I have not found the same. Furthermore, there are no empirical data to support it. To the contrary, most scientific evidence supports the notion that the rut occurs at roughly the same time each year, regardless of where the full moon falls on the calendar.

There are a lot of folks who will tell you that the worst time to hunt deer is during a full moon. Their claim is that deer move less, and less often, in daylight hours during this moon phase. In more than 30 years of deer hunting, that has certainly been my observation. However, there is no hard scientific evidence to substantiate it.

Then there's temperature. Old-timers will tell you it takes a good cold snap to jump-start the rut. That's not exactly right, but it's not entirely wrong, either. The calendar or the moon phase may be right, but, if it's been warm, daytime deer movement is usually slow.

Research clearly shows that deer activity drops off as daytime temperatures rise. Deer will still move, but they'll move a lot less once the mercury climbs much over about 45 degrees. When the time is right, the deer will rut. They'll just do it at night. Throw in a good old-fashioned cold snap, however, and they'll be on their feet all day long. Did the cold trigger the rut? No. But it did intensify daytime rutting activity.

And what about rain? As this year's one-day youth hunt clearly demonstrated, rain does influence deer movement. (Through the miracle of modern technology, we can tell you who won a ball game that ended at midnight last night, but we can't report on Maine's youth deer hunt until two weeks after it occurred.)

The research is a bit less committal: heavy rain may reduce deer movement. Meanwhile, I've seen it both ways and once shot a deer at the height of a good old-fashioned northeaster.

When you come right down to it, there are no easy answers to when is best to hunt. The white-tailed deer is, as Churchill once said of the Russians, "... a riddle, wrapped in a mystery, inside an enigma..."

We can do all the research we want, but deer don't read the scientific journals and so don't always do as they're supposed to. In the final analysis, the best time to hunt them is when the season is open.

Bob Humphrey is a freelance writer and Registered Maine Guide who lives in Pownal. He can be contacted at:

sportventures@juno.com