Skip to main content

Basic Biology of the Whitetail Rut

Basic Biology of the Whitetail Rut

Adolescence can be a rough period of life, both mentally and physically. Thankfully, we humans only have to experience it once. Imagine if you had to go through puberty every year!

In effect, that’s what a whitetail buck does each fall as he goes through the rut.

Purpose

The goal of the rut, according to Dr. Karl Miller of the University of Georgia, is “to maximize reproductive output in the spring.” It’s all driven by photoperiod, the amount of daylight on a given day. Light enters the deer’s retina, sending a signal through the optic nerve to the hypothalamus and then the pineal gland to inhibit the production of melatonin. At night, these impulses stop, causing melatonin to be released into the body. The gradual increase in melatonin due to the longer nights of fall and winter stimulates the hypothalamus and pituitary glands to secrete estrogen and testosterone — the rut hormones.

Miller noted that photoperiod is a much more precise trigger of seasonal changes in the north, and as a result, the rut is much more synchronous there. Northern regions have a wider and more dramatic range of daylight lengths, declining by approximately three minutes a day in autumn. The north also experiences a wide range of annual temperature changes — sometimes 100 degrees or more between summer and winter.


With such extreme seasonal fluctuations, it’s critical that fawns are born into a favorable environment in terms of temperature, security cover and forage, and that fawns are given as much time as possible to grow before the onset of the next winter. This necessitates that does be bred at the optimal time.


Studies have shown that peak whitetail breeding dates in the north are amazingly consistent. I once surveyed deer biologists from all across the whitetail’s range in the United States and Canada, and they agreed that peak conception dates fall at roughly the same time each year regardless of moon phase, weather patterns or other variables.

The southern photoperiod change is less dramatic and the climate less severe, so fawns born outside of peak birth periods have a greater chance of survival there. However, synchrony still has its advantages. By giving birth at roughly the same time, does can “swamp” predators with an abundance of prey, improving each fawn’s odds of survival.

Let the Games Begin

If peak breeding occurs around the same time each year, we can presume all of the other stages leading up to that do as well. The aforementioned surge in testosterone results in circulation to the antlers being cut off. Velvet dies and peels, and bucks begin rubbing it off. They also begin skill sparring, much like young boys wrestling. Bachelor groups are still together, but that won’t last long. Aggression gradually escalates to demonstrative sparring as bucks begin sorting out dominance. Adolescence has begun. Subordinates aren’t run off yet, and they may even groom dominants as a display of submission.

Meanwhile, making rubs begins to take on more importance. Through secretions from their forehead glands, dominant bucks communicate their status. According to Miller, one buck can make 1,000 or more rubs over a 90-day period each fall. Being able to communicate this way cuts down on actual physical interaction, which becomes more important as bucks become less tolerant of one another and as bucks and does seek one another out, which technically means they’ve entered the rut.


The next phase of the rut is establishing scrapes, which serve several functions. Scrapes provide a litany of information about their maker and visitors, including identity, age, health, social status and breeding condition.

Scrapes also help synchronize breeding physiology. Chemicals in the buck’s urine and scent glands stimulate the doe’s reproductive system, causing, among other things, ovaries to develop. According to Miller, if you take mature males away, breeding becomes less synchronous, which is often the case in heavily hunted populations with a high proportion of younger bucks.

Application

Once you have a benchmark, you can fine-tune your hunting strategy to specific stages of rutting behavior. With a phone call to your local or state deer biologists, you can find out roughly when peak breeding occurs in the areas you hunt. Then, adjust accordingly.


Peak chasing will be during the week or two leading up to peak breeding; prior to that, bucks will be more involved in rubbing and scraping. Bear in mind throughout the season that this is all based on “peak” breeding dates. There will always be a certain portion of rutting and breeding behavior occurring out of sync with the majority.

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Recommended Articles

See More Recommendations

Popular Videos

Center Shots: How to Improve Your Bow Tuning

Center Shots: How to Improve Your Bow Tuning

Field editor Bill Winke goes over steps you can take to improve the tuning on your bow.

First Look: Mathews Vertix Bow

First Look: Mathews Vertix Bow

"Petersen's Bowhunting" editor Christian Berg and Mathews design engineer Mark Hayes talk the smooth, quiet and fast shooting qualities of the new flagship Vertix bow from the Wisconsin bowmaker.

Springtime Turkey Hunt

Springtime Turkey Hunt

Kevin Steele and the boys are bowhunting turkeys with the help of some well-placed decoys.

Ravin Broadheads – 3 New Mechanicals

Ravin Broadheads – 3 New Mechanicals

Designed exclusively for their crossbows, Ravin has announced three new mechanical broadheads to maximize penetration and overall performance.

See More Popular Videos

Trending Articles

Crunching the numbers on North America's most important game species2020 State of the Whitetail Report Whitetail

2020 State of the Whitetail Report

Jason Snavely - June 29, 2020

Crunching the numbers on North America's most important game species

These boots are Field Tested: Danner Vital Snake Boots Apparel

Field Tested: Danner Vital Snake Boots

Taylor Pardue - July 13, 2020

These boots are "better safe than sorry" at its best.

This tasty venison lasagna recipe is the perfect wild game meal to serve at a potluck or large family gathering.Best Venison Lasagna Recipe Recipes

Best Venison Lasagna Recipe

Jenny Nguyen-Wheatley

This tasty venison lasagna recipe is the perfect wild game meal to serve at a potluck or large...

Follow these 4 steps to early-season success.How to Pattern Bucks in the Early Season Whitetail

How to Pattern Bucks in the Early Season

Clint Casper

Follow these 4 steps to early-season success.

See More Trending Articles

More Whitetail

Prepare now to ensure a victorious whitetail season this fall.The Perfect Game Plan for Bowhunting Whitetails Whitetail

The Perfect Game Plan for Bowhunting Whitetails

Bill Winke

Prepare now to ensure a victorious whitetail season this fall.

Crunching the numbers on North America's most important game species2020 State of the Whitetail Report Whitetail

2020 State of the Whitetail Report

Jason Snavely - June 29, 2020

Crunching the numbers on North America's most important game species

This time of transition for whitetails may be the best month to utilize your grunt calls. October's Quiet Woods Can Be Broken Up by Timely Grunts Whitetail

October's Quiet Woods Can Be Broken Up by Timely Grunts

Lynn Burkhead

This time of transition for whitetails may be the best month to utilize your grunt calls.

Understanding these phases can help you fine-tune your hunting strategy to specific stages of rutting behavior.Basic Biology of the Whitetail Rut Whitetail

Basic Biology of the Whitetail Rut

Bob Humphrey

Understanding these phases can help you fine-tune your hunting strategy to specific stages of...

See More Whitetail

Magazine Cover

GET THE MAGAZINE Subscribe & Save

Digital Now Included!

SUBSCRIBE NOW

Give a Gift   |   Subscriber Services

PREVIEW THIS MONTH'S ISSUE Arrow

Buy Digital Single Issues

Don't miss an issue.
Buy single digital issue for your phone or tablet.

Buy Single Digital Issue on the Petersen's Bowhunting App

Other Magazines

Special Interest Magazines

See All Special Interest Magazines

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Phone Icon

Get Digital Access.

All Petersen's Bowhunting subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit mymagnow.com and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now