Whitetail Deer and the Moon
In the past several years many different writers, including two who are deer biologists, have suggested that peak breeding of whitetails is related to the phase of the moon. Their predictions are based on the belief that the amount of light during particular phases of the moon affects melatonin production, which in turn regulates the production of hormones. Three of these writers, including the two deer biologists, feel that peak breeding should occur from 5 to 7 days after the full moon. The fourth writer feels that peak breeding should occur from 5 to 7 days before the new moon. These writers don't agree on the exact dates, but they do predict approximately the same time frame, because seven days after the full moon is the same day as seven days before the new moon. But, are their predictions correct?
To find out the answer to that question I looked at some data provided to me by Al Berner, the former Group Leader for the Minnesota Department of Natural Resources, Farmland Wildlife Populations and Research Group. Between 1980 and 1987 the Minnesota DNR conducted a study to determine the conception dates of over 1600 road killed whitetail does. The results of the study show that, for all eight years combined, approximately 80 percent of all the does over the age of 1 1/2 years old were breed between October 29th and November 26th, and that 24 percent of those does were bred between November 1st and November 7th. When I asked if there was any difference in breeding dates from year to year, I was told that peak breeding in Minnesota always occurred during the second week of November.
The November full moon occurred on Nov. 27, 1980; Nov. 11, 1981; Nov. 1, 1982; Nov. 20, 1983; Nov. 22, 1984; Nov. 27, 1985; Nov. 16, 1986; Nov. 5, 1987; and Nov. 23, 1988. In other words, during the time of the Minnesota conception date study, the November full moon occurred from as early as November 1st to as late as November 27th; and it occurred most often during the third week of November. But, the combined-year backdated conception dates show that peak breeding occurred during the second week of November. This shows that there was no correlation between peak breeding dates of white-tailed deer and any moon phase. In March, 2001, I spoke to well known deer researcher, Dr. Karl Miller, who had just completed a study of over 2500 white-tailed deer breeding dates in Maine, Michigan, Minnesota, Missouri, Georgia, Texas and Mississippi. He stated that he found no correlation between peak breeding activity of white-tailed deer and any lunar phase. His study also showed that breeding of whitetails is not affected by the moon.
So, why do so many writers and hunters believe that peak breeding of whitetails occurs shortly after the full moon? Two different research projects by whitetail biologists show that deer are more active during the full moon than they are during the other phases of the moon. One of those research projects, and my own research, shows that deer are seen more often during the full moon than other moon phases. If the full moon occurs during peak rut, and if more deer are seen at that time, it would explain why many writers and hunters believe peak breeding occurs shortly after the full moon.
If you want to hunt during the peak of the rut and you live above the 40th parallel, don't worry about the phase of the moon, hunt during the second week of November. If you want to know when the peak of the rut occurs in your area log on to the Trinity Mountain Outdoors web site at www.TRMichels.com and click on Peak Whitetail Rut Dates Chart. If you want to hunt during the rut when deer are most likely to be active during the day, find out when the full moon occurs. The best time to hunt should be from about three days before the full moon, to seven days after the full moon, especially if those days occur during the second week of November.
But, peak breeding may not be the best time to hunt, if you are looking to take a particular buck. Peak breeding in many areas may result in what has come to be known as "the buck lockup", when many of the older, larger racked bucks may stay with an estrus doe for up to three days. That means the bucks will not be traveling their normal daily pattern, leaving the daytime core areas in the evening, following rub routes and checking scrapes. Instead, they will follow the does as they come and goes from their daytime core area to nighttime food sources. However, those bucks that have not found an estrus doe, may be traveling throughout the day, looking for does at food sources and in or near their daytime core areas. In order to hunt those bucks you may have to stay in your stand all day, because you never know when a buck looking for an estrus doe may me moving; especially if the moon is in the full or last quarter phase.
If you are interested in more whitetail hunting tips, or more whitetail biology and behavior, click on Trinity Mountain Outdoor News and T.R.'s Hunting Tips at www.TRMichels.com. If you have questions about whitetails or whitetail hunting log on to the T.R.'s Tips message board. To find out when the rut starts, peaks and ends in your area click on Whitetail Rut Dates Chart.