T.AR.'s Tips; Understanding the Whitetail Rut

[TMichels]

This is from my book The Complete Whitetail Addict's Manual

The Rut
Most deer hunters know that whitetails act differently during the rut than they do at any other time of the year. After spending time with and talking to a number of different whitetail hunters, most of them experienced and some of them quite knowledgeable, I realized many of them did not understand the progression of the rut, or the time frame of the rut. Most of them knew that in the upper Midwest rubbing usually begins in September, scraping in mid-October, and that the “peak of the rut” occurs during the second week of November. But there seemed to be a difference of opinion about what the “peak of the rut” meant. To some it meant the time when they most often saw bucks during the day, usually the two weeks before the breeding phase. Others thought the peak of the rut meant peak breeding activity, which it does. Some thought all the breeding activity occurred during the week of the peak of the rut, and resigned themselves to the belief that once the peak of the rut was over no more breeding would occur. If they did not get a buck by the peak of the rut they believed there was no reason to hunt as hard, because there was less activity.

Rubbing, Scraping and Breeding Peaks
Rubbing, scraping and breeding all have their own time frames (which overlap each other), and their own peaks during the rut. Rut related activity in northern areas usually starts when bucks begin rubbing small trees and brush to remove velvet from their antlers and making scrapes. This may occur as early as late August or early September in area above the 38th parallel. Rubbing may peak in mid-September and generally diminishes throughout the rut, but it may rise again during later breeding phases. Scraping activity may begin as early as the first week of September, but without much activity until mid to late October. Breeding may begin in mid-October, and breeding begins to increase as scraping increases in late October. Scraping often peaks from mid to late October as bucks continue to make new scrapes and maintain existing scrapes. As breeding activity increases in early November scraping activity decreases. Breeding in northern areas may be intermittent from mid to late October; fairly continuous throughout November, with peak breeding occurring sometime between the first and the third week of November; and intermittent from early December into January. But, hold on what was that about breeding beginning in mid-October?

(This graph is on the "Rut Dates" page on my site.)

Data provided by the MN Department of Natural Resources

Note: The above graph shows the breeding dates of 1600+ does in Minnesota between 1980 and 1987. It clearly shows that that breeding of both yearling and older does begins in mid October and continues to mid January, for a breeding season length of 120 plus days. It shows that peak breeding during all years, and for all years combined, occurs during the second week of November. In addition, it shows that rarely do any more than 35 percent of the does in any one area get bred during the one-week time frame of the Peak of the Rut. It also shows that doe fawns in Minnesota breed from late October to early February; and that peak breeding of doe fawns occurs from late November to late December.

Estrus Cycles
Marchinton found that the estrus cycles of does ranged from 21 to 30 days, with an average of 26 days, and that does may recycle up to 7 times. My own observations, those of several other writers and photographers, and the studies of Dr. Larry Marchinton in Georgia show that breeding occurs as early as September 24 in northern Minnesota, October 15 in southern Minnesota, October 17 in Georgia, and October 24 in central Wisconsin.

Thanks to Marchinton's studies we can actually pinpoint estrus cycles in captive deer. The study was conducted to find out how many estrus cycles unbred does would experience. During the study recurrent estrus ranged from 2 to 7 times. Of the eight does studied one 2.5 year old came into a first estrus on October 17, another on October 24, three 1.5 year olds on November 11, one 2.5 year old on November 19, one 1.5 year old on November 21, and one 5.5 year old on December 1. The last recurrent estrus occurred on April 7.

This shows that, even without recurrent estrus, some does will be in estrus from mid-October to early December, resulting in a breeding period of more than 45 days. In northern areas the breeding period may last in excess of 60 days; from mid-October to late December. In southern areas it may last more than 90 days; into February. In most areas a small portion of the adult does may be bred in October, most of them in November, and a few more in December. This is typical of most deer populations. In northern areas 1.5 year old does may experience their first estrus in December. Doe fawns (5+ months) may experience their first estrus and breed in December, January or February.

Late Breeding Phase
As a result of Marchinton's study we know we cannot reliably predict when the late breeding phase may occur. Even if the majority of the does come into estrus at the same time, the research shows that recurrent estrus cycles are variable. Instead of occurring every 28 days as previously thought the cycles ranged from 21 to 30 days. This would make it difficult to pinpoint the late breeding period, especially when coupled with the knowledge that the first estrus of a doe may occur anytime from mid-October to mid-December. Another note of interest is that the does were in estrus from 24 to 48 hours, not the 22-24 hours previously thought. Any buck chasing a doe may spend up to three days with her without returning to its core area.

May God bless you and yours, and good hunting,

T.R.

[Quailhunter]

Great post TR.

[TMichels]

Thanks I'm gald you liked it. And I hope it helped.

God bless.

T.R

[Carolina Duckman]

Hey TR, Good stuff there. If you don't mind I'd like to share a little info on the place I manage here in the deep south. We have just over 6000 acres that have been managed intensely for over 20 years now. As we know deer density and buck to doe ratios play a big part of the equation. For 10 years we shot does, lots of does. Some years a hundred plus. Now we are shooting an average of around 50 a year for the last 10 years. All does are checked for fetuses which are measured and aged. As for bucks we try to harvest nothing under 4.5 years old. This past deer season Aug-Dec we logged 1,896 man hours on stand. We observed 417 deer, 170 bucks and 133 does were positivly identified giving us a 1.28 buck to doe ratio. Over the last 5 years(03-05) the ratio averaged at 1.22 bucks per doe. We collected 29 fetuses that were aged and sexed. From this we learned that the majority of the breeding activity was the last week of sept to mid Oct. This put a median date of Oct 3. Previous dates were Oct 12 in 07, Oct 4 in 06 and Sept 29 in 05. We have also seen that with this management practice that you buck fawn rate rises and you twin fawn rate rises. This year does 2.5 years old produced an average of 1.6 fetuses in which over 60% had twin fetuses and over 60% of those were bucks.


Sorry for butting in, I love this stuff !

[FastDuckMotors]

Nice TR, is there any way I can get you to blog on here about some of your stuff? It looks good!

[TMichels]

Carolina DuckMan.

Mind - heck no, I'm here not only here to share and teach, but to learn.

That is some very intersting stuff. It shows that management can alter the dates of peak breeding, and tht doe harvest can increase the number of fawns born each year (because you are keeping the # of deer below the carrying capacity of the habitat) and that buck harvest can actully i ncreas the # of bucks in the fetuses.

Keep up the good work.

God bless,

T.R.

[TMichels]

Fast Duck,

I'm guessing you Googled me, and found out I do a lot of reserarch and posting.

If you don't mind I'll post several of my articles on deer, elk, turkeys, ducks, geese, calling, scents, decoys, flagging, deer management and habitat conservation. What I like to do is run on-line seminars, where I post articles, and the guys get to ask questions, discuss what I wrote, and add there own .02 worth.

Let me know if that is okay.


God bless,

T.R.

[FastDuckMotors]

I have read some of your articles in the past and find your information very interesting and very informative. I look forward to your discussions. You are welcome to post anything you would like. We do have a online chat capability that can be utilized. I welcome your discussions. It is always nice to have when it comes to hunting!!

[Quailhunter]

I believe your discussions would be great information to our forum members and everyone could gain a great wealth of information.