When Whitetails Move: What Collar Studies Say About Sunrise and Sunset

STEP 1 · The baseline

Michigan reserve research predating GPS collars

In 1990, Beier and McCullough's George Reserve activity study was published as monograph 109 (Northern Arizona University record). During most months, deer had a daily activity rhythm with highs at sunset and a little after sunrise. Male and female patterns were alike apart from September and October. In those months, nighttime activity was greater among males, while daytime activity was greater among females.

Temperature also appears in the abstract's activity findings. The peak fell within 6 to 16 degrees on the Celsius scale, with lower activity at temperatures outside that band. The temperature effect varied with habitat and season as well as the time of day, wind speed and cloud cover. Even small snow depths reduced activity, which the authors connected to food. By day, deer used closed vegetation. They used open types at dawn, dusk and night. Percent of time spent active was the measure; it does not equal distance traveled. We read only the abstract.

STEP 2 · Oklahoma collars

Fifteen-minute locations, a familiar finding

Webb's team attempted location fixes at intervals of 15 minutes for 17 female deer and 15 male deer. The Oklahoma work covered three seasons over seven years (Webb et al. 2010). The abstract describes both sexes as moving mostly near dawn and dusk. Daily movement, movement after dark and movement during daylight were unaffected by moon phase. Short-term weather effects within a season did not follow a consistent pattern. In the authors' view, their data suggest little influence from hourly or daily weather changes on deer movement in southern latitudes. They presume a regular dawn-and-dusk routine helps deer manage body temperature and face less risk from predators. That reason remains their presumption, whereas the movement pattern was measured. For the moon-phase issue, see the guide to movement scores.

STEP 3 · Wisconsin rut window

Hourly rut locations from 188 bucks

Hunsaker and colleagues supply the data set most useful for planning a rut sit. They tracked 188 males with GPS collars in parts of Wisconsin's Dane, Grant and Iowa counties, during 2017 through 2020, starting 15 October and ending 1 December (Hunsaker et al. 2025; see the publication record). A location was logged each hour. Most land in the study area is private, with hilly deciduous woods, valley grasslands and fields of alfalfa, soybeans and corn.

Sunrise and sunset set the researchers' daily categories; fixed clock times did not. They counted dawn as the sunrise hour plus the preceding hour. Dusk included the sunset hour plus the following hour. The interval separating those periods was day, with all remaining hours assigned to night. Over the seven-week research period, those categories shifted as sunrise and sunset changed. Your hunting schedule should follow those shifts as well.

Changepoint analysis locates changes in daily movement patterns. It put peak rut in a window beginning 23 October and ending 12 November. Conception estimates supported that timing: researchers counted backward 200 days from birth dates estimated for fawns they captured. Both movement and range size rose into early November before shrinking. Two-year-olds had the fastest movement rates. Daily movement rates varied most among bucks aged 3 or older. The authors interpreted that variation as alternating bouts of searching with more travel and tending with less travel. The variance comparison between bucks aged two and older bucks yielded P = 0.06, falling short of the authors' cutoff. The authors also say a decline consistent with tending cannot establish that breeding has been completed.

How movement breaks down within a day is what changes a sit plan. Across age groups, movement was greatest in the week running from 5 to 11 November. During that stretch, bucks 3 and older had lower dawn movement than yearlings or bucks aged two. Yearlings, along with bucks aged two, moved slightly more during daylight than the older group. Dusk movement looked much alike among ages. After dark, both the older bucks and those aged two moved more than yearlings. At the peak, the oldest group showed indications of moving away from a dawn-and-dusk pattern toward a nighttime pattern.

Ohio's weekly reports provide a look at rut-season harvest in a different state. We examine them in Watching the Rut Happen.

STEP 4 · Midday in peak weeks

The depth of the midday lull

In November 2025, an article explained the study's figure for hunters (study coverage). Its description traces the familiar U: high movement around sunrise, a dip near midday and another high around sunset. This shape held through all six weeks as the curve's overall level rose or fell. The article puts the midday increase during weeks three and four, beginning 29 October and ending 11 November, at 50 to 100 meters each hour compared with the two weeks preceding or following them. Midday movement nevertheless remained below each twilight peak. The article quotes coauthor Dan Storm saying that a hunter still has a better chance of seeing bucks move during the evening on 15 October than on 4 November at noon. This account comes from the article rather than any numbered result within the paper; treat it as the researchers explaining their figure publicly. The article also describes those two weeks as offering better odds for an all-day sit than any other stretch of the season.

For hunters, these findings present a trade-off. Movement rises around midday during peak rut, but it still falls short of movement at dawn and dusk.

STEP 5 · Weather and pressure

What the Wisconsin model failed to detect

Give the two negative findings as much weight as the peaks. The best model for individual deer found no significant effect from year, weather, hunting season or where the firearm opening weekend fell on the calendar. Daily temperature lows and highs, plus the difference between those daily extremes, were considered by the authors. The firearm opener fell on the pre-Thanksgiving Saturday, beyond the peak: 18 November in 2017, 17 November in 2018, 23 November in 2019 and 21 November in 2020. Movement had begun to decline before the opener, which produced no detectable break. The authors also made a descriptive comparison, without a test. Across the four years, mean movement for 23 November came in about 6 percent below the 17 November mean. Comparing 23 November in 2019 against 17 November in 2018 gave a 19 percent lower mean. For that pair of years, Iowa County's firearm harvest of males dropped 25 percent as the opener changed from 17 November in 2018 to 23 November in 2019. The authors regard that agreement as a trend; many factors drive harvest.

Different measurements explain why the Michigan findings and Wisconsin findings do not contradict each other. On one reserve, Beier and McCullough found an activity-related band of temperatures over a year. Daily temperature was what Hunsaker's model examined during its seven-week window. We read the findings this way: temperature can influence the activity budget across a year, with the calendar dominating within the rut period. Storm's remark about the date within the year points the same way. Since the Wisconsin model addressed daily rates of movement, it cannot answer whether a front alters feeding locations during a day.

STEP 6 · Hunted ground

Evening twilight fared better

Two studies of collared deer on hunted properties treated dawn and dusk separately. Both also appear in our guide on collar studies and hunting pressure. In South Carolina, at Brosnan Forest, the average distance covered per half hour favored dusk over dawn for both sexes: bucks averaged 129 meters versus 95, and does averaged 114 meters versus 55 (Stewart et al. 2022). For bucks during the shotgun season in Maryland, movement at dusk and overnight exceeded dawn and daytime movement; travel during daylight also fell below the dawn rate (Karns et al. 2012). Those Maryland authors offer a likely explanation: after repeated disturbance along interior roads carrying hunters, deer returned from fields to their beds earlier each morning, but their evening feeding trip held steady. An extension bulletin reports higher rates of food-plot arrival by adult bucks just around sunset (extension bulletin P3927).

Wisconsin offers a loose fit. During peak week, dawn movement was lowest among the oldest bucks, yet dusk movement looked alike among ages. Use this as a lead drawn from three studies. Among those that separated dawn from dusk on hunted properties, dawn was the weaker twilight.

STEP 7 · Two clocks

Separate schedules for deer and slope air

The research discussed here follows deer timing. Hillside airflow follows another schedule, which none of these collar studies measured. In our wind-forecast guide, we advise expecting downhill drainage before daylight that continues until sunlight heats the slope. That often includes the first 60 to 90 minutes following sunrise. Our thermals paper describes why morning and evening airflow transitions overlap the periods deer use. This is our interpretation of airflow; these studies did not establish it.

A map layer can point out potential scent trouble. It leaves this morning's air drainage unanswered. None of the research discussed above tells you which direction your scent will travel.