Gray wolves follow white-tailed deer across Wisconsin (2018-2025), rising briefly after the 2021 wolf harvest

Damian Anthony Vraniak

Earlier analyses of county-level extracts of the Snapshot Wisconsin camera network suggested that gray wolves (Canis lupus) arrive at cameras shortly after white-tailed deer (Odocoileus virginianus), select antlered bucks, and displace deer, but their wolf samples were too small to settle whether following rose after the February 2021 wolf harvest, whether displacement weakens near development, and how wolves respond to people. I tested these with a statewide extract (7,791,771 detections, 5,371 cameras, 2018–2025; 461 sequential wolf–deer encounters) and ran the same measures for coyote, black bear, bobcat, and wild turkey, the last as a non-predator control. Wolves arrived after deer in 74% of encounters against 50% under a permutation null (P = 0.002), in every zone with wolves and at every level of local wolf activity, a median 5.9 min behind; in the hard-antler months the wolf's nearest deer was a buck 1.40× more often than availability predicted (P = 0.004). The harvest produced a pulse: following rose from 0.63 (2019–2020) to 0.83 (2022–2023; odds ratio 2.75, P = 0.002) and returned to 0.68 by 2024–2025, with no change in any other species. Deer returned 2.19× more slowly after a wolf than their baseline, and 2.5× more slowly than a random-instant null expects; the delay was larger in forest than farmland and declined with development, but did not vary across a 12-fold range of wolf activity. Against the same null, deer avoided people everywhere (2.1× the null), coyote, bear, and turkey modestly (1.1–1.15×), and wolf and bobcat not at all: the wolf's raw delay after a person is what sparse, clustered visits produce by chance. Following is the wolf's normal behavior, briefly intensified by the harvest; displacement is mediated by the landscape.