Does Moon Phase Actually Affect Deer Movement? What the Science Says

Pick up any deer hunting magazine and you'll find a lunar calendar tucked inside. Ask hunters when they plan their best sits and a large percentage will tell you they're watching the moon. But what does the science actually say?

The Studies That Tried to Settle This

The question has attracted serious scientific attention over the past two decades, with multiple universities deploying GPS-collared deer across the country. The results have been remarkably consistent.

Penn State Deer-Forest Study

The Penn State College of Agricultural Sciences surveyed 1,680 hunters about their lunar beliefs and simultaneously tracked GPS-collared adult deer in October 2015 and 2016. Their three key findings:

• Deer were more active at night than day during all three moon phases
• Peak activity occurred within two hours of sunrise and sunset — regardless of moon phase
• Moon phase had an insignificant effect on deer movement; deer moved roughly 6 meters more per hour under a new moon vs. full moon — a difference described as biologically negligible

Source: Penn State Deer-Forest Study, "Wandering in the Moonlight" (2017)

NC State / Marcus Lashley Study

Marcus Lashley at North Carolina State University compiled over 22,000 GPS fixes on live deer and correlated activity to moon phases. His findings:

• Deer moved most at dawn and dusk regardless of moon phase
• A slight increase in midday activity was observed during full moons
• Deer movements were greatest at dawn during new moons — a minor uptick, not a dramatic shift
• These were minor variations, not major increases over other moon phases

Source: Lashley et al., Journal of the Southeastern Association of Fish and Wildlife Agencies (2016)

Mississippi State University Deer Lab (2025)

In perhaps the most comprehensive modern study, the MSU Deer Lab team — including Dr. Steve Demarais and Dr. Bronson Strickland — tracked 48 collared bucks from September through February in Mississippi, looking specifically at both moon phase and moon position (overhead/underfoot).

They first surveyed approximately 1,400 hunters to establish what a "meaningful" lunar effect would look like — hunters said at minimum a 50-yard-per-hour increase in movement or a 30-minute earlier exit from the last afternoon bed.

The result: on the best possible solunar rating (a "4" — full moon with major window), bucks moved just 4 extra yards per hour with essentially no change in bedding time. As Lashley's colleague Luke Resop noted: "This is essentially the data you expect to see when there's no effect in a study."

Source: MeatEater / MSU Deer Lab study summary (2025); Mississippi Dept. of Wildlife, Fisheries & Parks summary

King Ranch Study (Dr. Mickey Hellickson)

Dr. Mickey Hellickson collar-tracked 43 bucks on the famous King Ranch in Texas, recording more than 420,000 GPS locations from October through January. His conclusion was direct:

"Although the moon may influence buck movements in other ways, our data did not indicate any patterns relative to the effects of moon phase on buck movements."

Source: Bowhunters United / Archery Trade Association (2025)

So Why Do So Many Hunters Believe It?

It's not irrational. The full moon is highly visible, memorable, and creates a compelling narrative. Dr. Grant Woods — a veteran deer biologist who once ran a lunar-based prediction system himself before abandoning it — explains the core problem with hunter observation data:

"Anything based on observed deer — what you see while hunting with your own two eyes — is biased. You're putting your best effort where you think you'll most likely see deer. Meanwhile, a GPS collar follows that deer everywhere, 24 hours a day."

There's also a timing coincidence at play. The rut — which does massively spike buck movement (bucks average nearly twice the hourly travel during peak rut vs. outside it, per the MSU study) — tends to fall near the same moon phases each year. Hunters may be correctly identifying increased activity but misattributing the cause.

What Actually Does Move Deer?

The research is consistent on a short list of genuine movement drivers:

The Better Alternative: Your Buck's Own Pattern

Here's the fundamental problem with any generic lunar or weather calendar: it's built on population-level averages across thousands of deer in different habitats, geographies, and hunting pressures. Your buck isn't average. He has his own pattern — his own preferred temperatures, his own wind directions, his own time-of-day tendencies.

Trail cameras capture exactly that. Every photo has a timestamp. That timestamp corresponds to a specific temperature, barometric pressure, wind direction, and moon phase on that exact day and location. Over a season or two of photos, patterns emerge that are specific to your deer, your property, and your micro-climate.

That's the data that gives you an actual edge — not a generalized lunar calendar based on deer hundreds of miles away.