Wolf–Deer Camera-trap Detections Across Wisconsin’s Statewide Wolf Range (2018–2025): A Temporary Increase in Wolves Following Deer After the 2021 Wolf Harvest, Displacement Effects by Habitat Zone, and Avoidance of People Across Co-occurring Species

Damian Anthony Vraniak

Two prior analyses of wolf-enriched extracts of the Snapshot Wisconsin camera network — one county, then five northwestern counties — showed that gray wolves (Canis lupus) tended to arrive at cameras shortly after white-tailed deer (Odocoileus virginianus), that they arrived after antlered bucks more often than the bucks’ numbers would predict, and that deer returned to a site more slowly after a wolf has passed than after a person (Vraniak 2026b, 2026c). Those analyses also reported three patterns their wolf sample was too small to settle: a rise in following after the February 2021 wolf harvest, weaker displacement of deer by wolves near towns, and a long delay before a wolf returns to a site after a person has passed. Here I tested all three with an extract built by the same data pipeline, but statewide: 7,791,771 detections on 5,371 cameras (2018–2025), including 7,742 wolf detections on 810 cameras and 461 sequential wolf–deer encounters — four times the five-county count. I also ran the same measures for coyote, black bear, bobcat, and wild turkey. The turkey, which poses no danger to deer, served as a control. Before the new analyses, the statewide extract reproduced every published five-county value exactly. The statewide analyses produced four results: (1) Wolves arrived after deer in 74% of encounters, against 50% expected by chance (P = 0.002). This held in every Deer Management Zone that had wolves and at every level of local wolf activity. The median gap between deer and wolf detection stayed near 5.9 minutes in every subset. In the hard-antler months (September–December), an antlered deer is reliably a buck. In those months, the wolf’s nearest deer was a buck 1.40× more often than the bucks’ share of deer at the same cameras would predict (P = 0.004). During the October–November rut the selection rose to 1.48×. The same test run across the whole year found almost nothing (1.10×), because for most of the year antlers cannot separate the sexes. (2) The hunting harvest of wolves produced a temporary increase in wolves following deer, a pulse, not a lasting change. Setting aside the hunting year 2021 itself and comparing the two years before the wolf harvest (2019–20) with the two years after (2022–23), the following rose from 0.63 to 0.83 (Fisher’s exact P = 0.0019; odds 2.77× with zone held constant). By 2024–25 the fraction (0.68) had returned to the pre-harvest level (P = 0.43). No other species changed across the same years: the coyote’s following deer fractions in the same two windows were 0.61 and 0.62 (13,461 encounters), and bear and turkey were also unchanged. (3) Deer returned 2.19× more slowly after a wolf than their own usual return interval. The delay was larger in forest zones than in farmland (2.38× vs 1.71×, P = 0.020). It also declined steadily as development increased, on the corrected 1-km human-modification index: 2.53× on the wilder half of the cameras, 1.86× on the more-developed half (P = 0.009). The delay did not change across a twelve-fold range of local wolf density (P = 0.22); that is, deer used wolf-rich and wolf-poor cameras equally (r = −0.005). Deer also returned 1.53× more slowly after a turkey. That value estimates the part of any such delay that has nothing to do with danger; the wolf’s delay stands well above it, while the bear’s (1.56×) does not. That pooled bear value carries a caveat. Compared in season (June–November) and by deer class, against class-specific turkey references on the same cameras, the bear’s delay stood above the reference for every deer class. (4) Wolves returned 2.42× more slowly after a person — the largest value among the deer–wolf–human comparisons — and the delay differed by zone: 3.06× at farmland cameras, 1.35× in the Central Forest. The deer’s delay after a person was nearly the same everywhere (1.82–1.92×). Ranked across species, the return delay after a person ran: turkey 5.03×, bear 3.91×, coyote 2.50×, wolf 2.42×, bobcat 1.85×. The most heavily hunted species showed the longest delays. I interpret the wolf hunting harvest effect as a pulse, a temporary change in wolf behavior that faded as the population began to recover. The displacement results were a response set off by each passage, sized by the surrounding landscape – larger in forests than farms - and unaffected by how often wolves are present.