The Hunter’s Pulse: Non-target consumer use, hunter participation, and prey behavior shift in reference to hunter bait sites

Abstract

The hunting hypothesis emphasizes the importance that hunting has had on the development of the human species. Anthropologists often credit hunting with tool development, increased meat eating, and larger brain size (Domínguez-Rodrigo 2002). One such tool, or method, that hunters developed was the use of bait to attract animals to an ideal hunting location. This centuries old method is even recognized as one possible reason for animals domestication (Svizzero 2016). Today this hunting method is used around the world to lure animals away from places such as farm fields, increase herd size or supplement feed in winter, or for the original purpose, hunting (Litvaitis and Kane 1994, Smith 2001, Putman and Staines 2004). Baiting for the purpose of hunting is controversial among the wildlife managers, the public, and hunters alike (Peyton 1989, Dunkley and Cattet 2003). It challenges the hunting ethic of fair chase that values the pursuit of an animal and emphasizes the fairness of the capture and kill (Morris 2013). Conversely, the idea of an ethical shot stresses a quick kill with minimal suffering (Stokke et al. 2018). Hunting over bait increases the possibility of an ethical shot and increases the likelihood of harvesting an animal. Though baiting has proven to be an effective method for attracting target species to bait for the purpose of hunting, it does not come without consequences to the bait consumers. For example, black bears in Wisconsin that frequent bait often limit hibernation time to maximize bait consumption (Kirby et al. 2019). This results in shorter telomere length consequently impacting cellular aging (Kirby et al. 2019). Impacts and visitation of non-target species to bait is less known, however. In this dissertation, I focus on three aspects of hunter bait: non-target species use of black bear bait (chapter 1 and 2), gray wolf (Canis lupus) olfactory cue impacts on white-tailed deer (Odocoileus virginianus) behavior at deer hunter bait (chapter 3), and wolf space use shifts in relation to black bear hunter bait (chapter 4). In Chapter 1, I focus on non-target species use of black bear bait in the Upper Peninsula (UP) of Michigan. Baiting for bears in the United States, and in particular Michigan, is a common practice used to attract bears to a central location and create a good shooting opportunity. Hunters often use a recipe of pastries, fruits, grains, and meat products to create an enticing slurry to attract bears. This formula is not only likely to attract bears, but also non-target species that find the bait attractive. Though research has looked into nontarget species use of white-tailed deer bait, the extent of visitation by nontarget species to black bear bait sites is unknown (Bowman et al. 2015). To fill this research gap, I carried out a study using remote cameras and pseudo black bear bait sites to record nontarget species use of black bear bait. I collected data at 21 pseudo bear bait sites in the Baraga Hunting Unit in the UP of Michigan over the course of six weeks in August and September 2016 collecting 8,642 pictures. Using a paired t-test, I evaluated black bear and carnivore non-target species use of hunter bait sites before and during the hunting season. I found that black bears reduce their daily visitation during hunting season while all other carnivore species increase their visitation. I also used a nonparametric kernel density estimation procedure to compare diel activity of the same species between the two time periods and found that black bears become more nocturnal during the hunting season while most other carnivores maintain their diel activity between both time periods. In Chapter 2, I demonstrate the potential of observations from remote cameras that hunters use at their bear bait sites and report via hunter surveys to be an effective method to monitor multiple species. Monitoring wildlife is essential for wildlife managers to understand population trends and adjust management plans. As technology advances, new wildlife monitoring techniques come on board and enable managers and researcher to better understand many aspects of wildlife populations. Remote cameras are one such technology that has enabled researchers to better understand the occupancy as well as spatial and temporal patterns of different species (Wang et al. 2015, O’Malley et al. 2018, Candler et al. 2019). As remote cameras become increasingly more affordable, the public has become increasingly interested in using them to peer into the lives of wildlife that share their spaces (Lasky et al. 2021). Hunters, in particular, have become interested in using remote cameras to investigate the species that are walking their hunting trails or visiting their bait sites. As hunter use of remote cameras become more widespread, more data are being collected, but currently those data are going unrecorded by researchers. In this chapter, I demonstrate how hunter surveys, commonly used to collect target species harvest and hunter satisfaction data, can be an effective tool for collecting hunter recorded remote camera images for multiple species. I collaborated with the Michigan Department of Natural Resource (DNR) to add questions to the annual Michigan Black Bear Hunter Survey regarding hunter remote camera use as well as animals they see at their bait sites. I compare remote camera image results from pseudo black bear hunter bait sites in fall of 2016 to remote camera observation from hunters reported via hunter surveys in the same hunting unit over the same time. I also test the effectiveness of these reports to be and index for multiple species by comparing them to gray wolf survey, mustelid (Mustelidae) trapping, and deer hunter harvest reports from 2016-2018. Using a Fisher exact test, I found that hunter reports are a useful tool for reporting remote camera images for four of the six species observed. Additionally, using Pearson’s correlation coefficients and simple linear regression models, I found that these hunter reported remote camera images have great potential to be an effective way of indexing multiple species. In Chapter 3, I illustrate the behavioral effect that a predator has on a naïve and an experienced prey population at hunter bait. For similar reasons to bear baiting, hunters use bait to attract deer to a central location to create a good shooting opportunity. However, deer are not the only species attracted to deer hunter bait (Bowman et al. 2015). Other species, such as wolves, have been recorded visiting hunter bait, even scent marking (Ruid et al. 2009, USFWS: Q and A’s about Gray Wolf Biology 2011, Bowman et al. 2015). These olfactory cues left by wolves are likely to impact the intended bait target, deer, by changing their vigilance behavior or time spent at the bait site (Melchiors and Leslie 1985, Kuijper et al. 2013, Chamaillé-Jammes et al. 2014, Wikenros et al. 2015, Sahlén et al. 2016). However, research has demonstrated that naïve prey do not maintain an innate threat sensing ability when it comes to extirpated predators (Berger et al. 2001). Therefore, we would expect deer would not change their behavior around bait visited by wolves in areas where wolves have been extirpated and remain absent, such as the Lower Peninsula (LP) of Michigan. However, in areas where wolves are established, such as the UP of Michigan, we would expect deer to be more vigilant and spend less time at bait that has been visited by wolves. In this chapter, I experimentally test the behavioral reaction of deer to wolf urine at deer hunter bait sites for both wolf savvy and wolf naïve white-tailed deer populations in Michigan. In September to November 2018, I constructed 30 deer bait sites between the UP and LP and used a before, after, control, impact (BACI) design with three treatment types (water, lemon juice, or wolf urine). Using remote cameras, I recorded white-tailed deer images and evaluated deer behavioral metrics and diel patterns before and after treatment, among treatments, and between the UP and LP. By analyzing 213,264 images and comparing the difference in behavioral metrics before and after treatment, I found that wolf urine had little effect on deer behavior in either area. However, when vegetation cover was compared to vigilance intensity using generalized linear models, a significant pattern emerged in the UP where wolves are present, but not in the LP, where they are absent. This indicates that vegetative obscurement, not predator olfactory cues, have more impact on savvy deer population vigilance. In Chapter 4, I consider the impacts that a predictable hunter food source has on the movement of a predator. Predator-prey systems are rarely simple systems with a single predator and single prey. Looking at predator-prey interactions through this simple lens will produce an incomplete picture of the ecosystem process. A complete understanding of predator-prey interactions requires consideration of all consumers and prey or other food in the ecosystem, including consideration of scavenged food sources such as anthropogenic food. Anthropogenic subsidies can act as an alternative food source, taking pressure off other prey species (Baruch-Mordo et al. 2014, Ciucci et al. 2020). Alternatively, it can increase pressure on prey by improving predator fitness (Robb et al. 2008, Oro et al. 2013, Plaza and Lambertucci 2017). Before the effects that these anthropogenic inputs have on predator-prey systems can be understood, the extent of use by predators needs to be understood. In this chapter, I focus on wolf movement shifts in relation to black bear hunter bait in the Greater Voyagers Ecosystem (GVE). I conduct a preliminary analysis of six GPS collared wolves in the GVE and their recursion movements in relation to black bear hunter bait sites, homesites, and other site types for the baiting and hunting time periods in the GVE from 2017-2019. Using student’s t-test and a nonparametric kernel density estimation procedure, I found that black bear bait sites are returned to often during the baiting and hunting periods, but that visitation becomes shorter and more nocturnal during the hunting season. For the remainder of this dissertation, I will use ‘we’ instead of ‘I’ to reflect that multiple people made this work possible. The first chapter of this dissertation is published in Human–Wildlife Interactions (Candler et al. 2019) and Chapter 2 is in published in Conservation Science and Practice (Candler et al. 2021).