Metadata Bucks

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Thanks to research, we know more about whitetails than ever. But is it possible for hunters to suffer from information overload?

Are deer hunters suffering from information overload? (Ryan Orndorff illustration)

Biologists have researched the habits of whitetails for decades, and there’s a lot of data available. But how much of the information out there is actually relevant to deer hunters? As with many scientific discussions, the answer is: It varies. But when hunters collect their own intel and then pair it with the data documented by professionals, interesting trends emerge. And those trends just might help you fill your next buck tag. Take these points, for example: 

Home Ranges and Core Areas 

Annual home ranges vary a good bit from one buck to the next — from 250 to 2,000 acres, according to QDMA biologist Matt Ross — and they change seasonally. Home ranges are smallest in the spring, and generally largest during the peak rut. No surprise there. 

Despite all the variance in home ranges, studies have shown some consistent themes in core areas, where a deer will be 50% of the time. No matter how big a buck’s home range may be — where he spends 90% to 95% of his time — his core area is typically about 10% to 15% the size of his overall home range, Ross says. 

Better yet, at least for the hunters who can pinpoint an old buck’s bedroom, home ranges and core areas tend to shrink as bucks get older. 

Hunting Pressure

The effects of hunting pressure vary by situation but one thing is for sure: Deer do respond to it. “When pressure increases, deer reduce space use and general movement, and increase the complexity of their paths, as well as use more secure cover. Their harvest susceptibility decreases,” Ross says. “It takes about three-plus days for deer to return to the patterns that they had before being pressured.”

It’s no surprise that spreading hunters out over larger acreage reduces the impacts of hunting pressure. “There is a really good study out of Noble Foundation in Oklahoma,” Ross says. “They showed an impact at one hunter per 75 acres of huntable land but little to no impact at one hunter per 250 acres of huntable land.”

Still, regardless of property size or hunting pressure, mature bucks are extremely loyal to their home ranges and core areas. The research shows it takes a lot to provoke them to relocate. “You basically can’t make him leave (his home range),” Ross adds. “You just make him change how he uses the space based on your presence.”

Weather

Most hunters believe weather is a critical component in how deer behave. But it’s been a difficult thing for researchers to prove. “There is actually very limited data that shows any strong correlation between most weather attributes and deer movements,” Ross says. “Lots of projects have looked at this, going back to the 1970s with radio collars and as recently as a few years ago with modern GPS technology.” 

Still, there is some conflicting data out there. And few hunters who’ve spent significant time in the field would argue that weather makes no difference at all to deer movement. Same goes for barometric pressure. Many hunters swear by the theory that rising pressure, around 30, spurs sudden movement. But again, Ross isn’t aware of any modern scientific data showing that it makes any difference to deer movement. 

Wind speed has been documented to make a difference, and perhaps not in the way you might think. From 2013 to 2016, a group of Penn State researchers studied deer movement in relation to wind speeds. Their findings revealed that incremental increases in wind speed sparked increased distances covered during daylight. And once winds surpassed 16 miles per hour, daylight movement increased exponentially.

“Not only did bucks increase their movement on windy days, but it only takes a light air movement to cause them to increase their activity,” says Jessica Hepner, a former PSU undergrad who helped conduct the research. “Bucks seem to like stronger winds and move more no matter how strong the breeze … while females don’t really care either way.”

Pinning down the science of how deer movement is influenced by things like weather and moon phase has been difficult. Still, many hunters believe the effects are nonetheless real. (Russell Graves image)

Moon Phases 

Plenty of hunters have opinions on moon phases and deer movement. One old theory is that deer move more on full moons and less on new moons — or vice versa. Another is that the “rutting moon” sparks the breeding phase of the whitetail rut. A relatively new theory is the moon overhead/underfoot concept, which says deer are likelier to move when the moon’s position is directly overhead or underfoot. Personally, I’ve experienced quite a few hunts that seem to support that.

But to this point, the science of the moon’s effect on deer is inconclusive. It definitely has no effect on the rut. Extensive studies have proven the primary trigger for does entering estrus is photoperiod — or daylight length — which occurs at the same time each year. Fawn fetus back-dating studies have supported this, too. As to whether certain moon phases or positioning makes a difference to deer movement, the science doesn’t support it. But many hunters believe it regardless. 

Collect Your Own Data

The most practical way to use the information documented by professionals is to compare it to your own firsthand observations from the field. To do that, you need to write things down.  

“Collect data when you hunt and some basic data from the deer killed,” Ross says. “Simply writing down when and where you hunt, for how long, and what you see provides a world of free info.” 

To drill even deeper, use apps to analyze conditions vs. trail camera photos and in-the-field sightings. Perhaps you’ll discover a direct correlation between a particular hunting condition and whitetail movement. Create new and revisit old journal entries. Gauge localized peak rut dates. Reflect on the details of past hunts — especially those that were successful or nearly so. 

Look through old trail camera photos of mature bucks you plan to hunt this season. Past information can provide a preliminary game plan for future hunts. New trail camera intel is important, too, especially when determining current home ranges, core areas, travel routes, and habits. You can even determine a buck’s personality with trail camera photos, especially in video mode. Identify their weaknesses.

Chart everything on an aerial map for a target buck, and keep a different map for each year of history. Use every available sighting and trail camera photo as a data point to help illustrate how a buck uses the property.

Most deer seasons are only as good as the effort invested, but it’s not all hands-on work, planting food plots and hanging stands. Using data to create smart hunting plans for killable bucks is one huge advantage. Information overload? No way. When it comes to hunting mature bucks, you can never know too much.