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Total number of black bears (Ursus americanus) killed by vehicles by year in northern Georgia, 1986-2014.
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An understanding of black bear (Ursus americanus) population trends and cause-specific mortality is needed to direct management decisions in northern Georgia given an increasing human population. Therefore, we evaluated black bear population trends and mortality sources across 26 counties and 18 Wildlife Management Areas in northern Georgia from 19...
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Context 1
... is further illustrated by an increasing number of bear- vehicle mortalities from 1986-2014 (min = 0 [1987 and 1988]; x ¯ = 16.6; max = 68 [2009]; Figure 4). We also found a positive re- lationship between the number of bear-vehicle mortalities and the increasing bear population ( β = 0.0019; SE = 0.0002; r 2 = 0.57; P < 0.001; Figure 5). ...
Context 2
... is further illustrated by an increasing number of bearvehicle mortalities from 1986-2014 (min = 0 [1987 and 1988]; x ¯ = 16.6; max = 68 [2009]; Figure 4). We also found a positive relationship between the number of bear-vehicle mortalities and the increasing bear population ( β = 0.0019; SE = 0.0002; r 2 = 0.57; P < 0.001; Figure 5). ...
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... Deer population declines in northern Georgia WMAs became evident during the early 2000s [18,19]. Simultaneously, populations of black bears (Ursus americanus; [28]), coyotes (Canis latrans; [29,30]), bobcats (Lynx rufus; [31]), and wild pigs (Sus scrofa; [32]) increased, and forests matured [18]. Deer population declines in the study area were attributed to an extremely low fawn survival rate (16% survival of 71 fawns monitored to 12 weeks of age during 2018-2020; [33]), primarily due to predation by black bears, coyotes, and bobcats [34]. ...
Simple Summary
Hunting can have direct effects (i.e., mortality) and indirect effects (i.e., behavior changes, such as shifting away from foraging areas to circumvent risk from hunters) on white-tailed deer (Odocoileus virginianus). Deer populations within the Chattahoochee National Forest of northern Georgia, USA, have declined significantly since the 1980s. Since deer population sustainability is a concern, understanding the potential negative effects of hunting on female deer is important. During the 2018–2019 and 2019–2020 hunting seasons, we evaluated the indirect effects of 7 firearms hunts for male deer on 20 non-target female deer. We used GPS locations recorded every 30 min during pre-hunt, hunt, and post-hunt periods to calculate and compare movement rates during the day and night, as well as the size and landscape characteristics of the space the deer utilized. Our results suggest that the low level of hunting pressure in our study area led to no biologically significant changes in female deer movements. To the extent of the findings presented in this paper, adjustments to the management of hunting in our study area do not appear to be necessary to minimize hunting-related disturbances for female deer. However, managers should continue to consider female deer behavior when evaluating future changes to hunting regulations.
Abstract
Perceived risk associated with hunters can cause white-tailed deer (Odocoileus virginianus) to shift their activity away from key foraging areas or alter normal movements, which are important considerations in managing hunting and its effects on a population. We studied the effects of seven firearms hunts on the movements of 20 female deer in two Wildlife Management Areas within the Chattahoochee National Forest of northern Georgia, USA, during the 2018–2019 and 2019–2020 hunting seasons. Deer populations and the number of hunters in our study area have declined significantly since the 1980s. In response, hunting regulations for the 2019–2020 hunting season eliminated opportunities for harvesting female deer. To evaluate the indirect effects of antlered deer hunting on non-target female deer, we calculated 90% utilization distributions (UDs), 50% UDs, and step lengths for pre-hunt, hunt, and post-hunt periods using the dynamic Brownian bridge movement model. Data included 30 min GPS locations for 44 deer-hunt combinations. Pre-hunt 50% UDs (x− = 7.0 ha, SE = 0.4 ha) were slightly greater than both hunt (x− = 6.0 ha, SE = 0.3 ha) and post-hunt (x− = 6.0 ha, SE = 0.2 ha) 50% UDs (F = 3.84, p = 0.03). We did not detect differences in step length, nor did we detect differences in size or composition of 90% UDs, among the periods. Overall, our results suggest that the low level of hunting pressure in our study area and lack of exposure to hunters led to no biologically significant changes in female deer movements. To the extent of the findings presented in this paper, adjustments to the management of hunting in our study area do not appear to be necessary to minimize hunting-related disturbances for female deer. However, managers should continue to consider female deer behavior when evaluating future changes to hunting regulations.
... Interstates and highways (rd. major), which if not acting as barriers, may inhibit gene flow by heightening mortality rates (Little et al., 2017). We did not explore the influence of other anthropogenic activities such as agriculture or human settlements because the former is uncommon and sparsely distributed across New Mexico while the latter is correlated with road density. ...
The phylogeography of the American black bear (Ursus americanus) is characterized by isolation into glacial refugia, followed by population expansion and genetic admixture. Anthropogenic activities, including overharvest, habitat loss, and transportation infrastructure , have also influenced their landscape genetic structure. We describe the genetic structure of the American black bear in the American Southwest and northern Mexico and investigate how prehistoric and contemporary forces shaped genetic structure and influenced gene flow. Using a suite of microsatellites and a sample of 550 bears, we identified 14 subpopulations organized hierarchically following the distribution of ecoregions and mountain ranges containing black bear habitat. The pattern of subdivision we observed is more likely a product of postglacial habitat fragmentation during the Pleistocene and Holocene, rather than a consequence of contemporary anthropogenic barriers to movement during the Anthropocene. We used linear mixed-effects models to quantify the relationship between landscape resistance and genetic distance among individuals, which indicated that both isolation by resistance and geographic distance govern gene flow. Gene flow was highest among subpopulations occupying large tracts of contiguous habitat, was reduced among subpopulations in the Madrean Sky Island Archipelago, where montane habitat exists within a lowland matrix of arid lands, and was essentially nonexistent between two isolated subpopulations. We found significant asymmetric gene flow supporting the hypothesis that bears expanded northward from a Pleistocene refugium located in the American Southwest and northern Mexico and that major highways were not yet affecting gene flow. The potential vulnerability of the species to climate change, transportation infrastructure, and the US-Mexico border wall highlights conservation challenges and opportunities for binational collaboration.
... Linear-water features (streams) contain food, escape and thermal cover, and are travel corridors (Atwood et al., 2011;Johnson et al., 2015). Roads can elicit negative behavioral and genetic effects and can influence bear distribution (Dixon et al., 2007;Gould et al., 2019), so we assessed their effect by estimating road density (rd.density), and interstates and highways (rd.major), which if not acting as a barrier, may still inhibit gene flow by heightening mortality rates (Little, Hammond, Martin, Johannsen, & Miller, 2017). ...
The phylogeography of the American black bear (Ursus americanus) is characterized by isolation into glacial refugia, followed by population expansion and genetic admixture. Anthropogenic activities, including overharvest, habitat loss, and transportation infrastructure, have also influenced their landscape genetic structure. We describe the phylogeography of the American black bear in the American Southwest and northern Mexico and investigate how prehistoric and contemporary forces shaped genetic structure and influenced gene flow. Using a suite of microsatellites and a sample of 550 bears, we identified 14 subpopulations organized hierarchically following the distribution of ecoregions and mountain ranges containing black bear habitat. The pattern of subdivision we observed is more likely a product of postglacial habitat fragmentation during the Pleistocene and Holocene, rather than a consequence of contemporary anthropogenic barriers to movement during the Anthropocene. We used linear mixed-effects models to predict genetic distance among individuals, which indicated that both isolation by resistance and geographic distance govern gene flow. Gene flow was highest among subpopulations occupying large tracts of contiguous habitat, was reduced among subpopulations in the Madrean Sky Island Archipelago, where montane habitat exists within a lowland matrix of arid lands, and was essentially nonexistent between two isolated subpopulations. We found significant asymmetric gene flow supporting the hypothesis that bears expanded northward from a Pleistocene refugium located in the American Southwest and northern Mexico and that major highways were not yet affecting gene flow. The potential vulnerability of the species to climate change, transportation infrastructure, and the U.S.-Mexico border wall highlights conservation challenges and opportunities for binational collaboration.
... The first deer hunt was held in 1940 (Little et al. 2018) and populations continued to increase until declines became evident during the early 2000s. Over the same time period, populations of black bears, coyotes, bobcats (Lynx rufus), and wild pigs (Sus scrofa) increased (Kilgo et al. 2010, Roberts and Crimmins 2010, Crimmins et al. 2012, Little et al. 2017, Lewis et al. 2019, while forests matured (Little et al. 2018). Predation, competition, and lack of early successional plant communities and early forest stages have been suggested as potential contributors to deer population declines (Little et al. 2018). ...
White‐tailed deer (Odocoileus virginianus) populations and deer hunter participation on federal public lands within the Appalachian Mountains of the southeastern United States have been declining over the last 30 years. Our study focused on Chattahoochee National Forest hunters in North Georgia, a region that has sustained a 64% decline in buck harvest success rates and 68% decline in hunter participation during 1979–2018. To better understand factors influencing satisfaction of remaining hunters, we sent mail questionnaires to 1,271 hunters in February 2019. We received 441 completed questionnaires for a 36% adjusted response rate. First, we used principal component analysis to identify 4 unique motivations for deer hunting: 1) escaping the daily routine and spending time outdoors, 2) harvesting deer for food, 3) socializing with hunting partners, and 4) harvesting trophy bucks. Second, we used ordinal logistic regression, which indicated that perception of a low deer population density was associated with lower levels of satisfaction. Perception of the right number of hunters on the landscape was associated with higher levels of satisfaction. In addition, greater importance ratings of harvesting trophy bucks were associated with lower satisfaction levels. Last, we applied revised importance‐performance analysis to 19 aspects of WMA deer hunting, which revealed that managers should focus on increasing opportunities for hunters to see deer and harvest bucks for the best chance at improving hunter satisfaction. Considering the 64% decline in harvest success rates between 1979 and 2018, the positive relationship between hunter satisfaction and perception of deer density, and hunter desires to see more deer and have more opportunities to harvest bucks, we recommend managing the deer population to increase numbers. Overall, our findings suggested that hunters and managers agree on the direction of deer management on North Georgia public lands for the near future. © 2021 The Wildlife Society. White‐tailed deer (Odocoileus virginianus) populations and hunter participation on federal public lands within the Appalachian Mountain region of the southeastern United States have declined over the past 30 years. Based on a 2019 mail survey of Chattahoochee National Forest deer hunters in the Appalachian Mountains of North Georgia, USA, managers should prioritize increasing opportunities for hunters to see deer and harvest bucks in order to increase hunter satisfaction.
... In one example of widespread human-carnivore interactions, conflicts between people and the American black bear (Ursus americanus) have been steadily increasing throughout the United States in recent decades [8][9][10]. Populations of both black bears [11,12] and humans have grown country-wide, leading to more interactions between people and bears [13]. ...
Black bears ( Ursus americanus ) are an iconic and common species throughout much of the United States and people regularly interact with these large predators without conflict. However, negative interactions between people and bears can manifest in conflicts that can hinder conservation efforts. Black bears are highly attracted to anthropogenic sources of food, and negative interactions with people are primarily a product of trash mismanagement. In the Catskills region of New York State, home to a large population of black bears, over 400 such conflicts are reported each year. While the New York Department of Environmental Conservation (DEC) has seen progress recently in educating residents of the region on how to reduce unwanted interactions with bears, they have had less success educating the 12 million tourists that visit the Catskills each year. Understanding where conflict may occur in the future, and the environmental and anthropogenic factors that precede it, may help guide management strategies to reduce these unwanted interactions. Therefore, we designed resource selection probability functions (RSPFs) to examine the relationship between human-black bear conflicts in the Catskills with a suite of landscape and anthropogenic data, using conflicts reported to the DEC across the state of New York in 2018–2019. We found that human-black bear conflicts were more likely to occur in the residential areas of the Catskills on the urban-wildland interface; areas with relatively higher human population densities, away from dense forest, and further from heavily urbanized areas. While future work is needed to continuously validate our model predictions, our results will provide the DEC and other conservation managers in the Catskills the ability to create more targeted plans for mitigating unwanted human-black bear interactions, and provide a better understanding of the mechanisms driving human-carnivore interactions at an urban-wildland interface more generally.
... Our results also suggest that habitat use is influenced by road density, but to a much lesser degree than primary productivity. The negative relationship between road density and habitat use is consistent with a large body of research that has highlighted the negative impact of roads on ursids, including increasing habitat loss, reducing habitat quality, heightening genetic isolation, and increasing mortality rates (Dixon et al., 2007;Little et al., 2017). Roads are also negatively correlated with habitat use of other mammals, from marsupials to small rodents and large-obligate carnivores with greater impacts on species exhibiting low reproduction and high vagility (i.e., highly-mobile species; Kerley et al., 2002;McAlpine et al., 2006;Kelly et al., 2013;Rytwinski and Fahrig, 2011). ...
Occupancy models have become a valuable tool for estimating wildlife-habitat relationships and for predicting species distributions. Highly-mobile species often violate the assumption that sampling units are geographically closed shifting the probability of occupancy to be interpreted as the probability of use. We used occupancy models, in conjunction with noninvasive sampling, to estimate habitat use and predict the distribution of a highly-mobile carnivore, the American black bear (Ursus americanus) in New Mexico, USA. The top model indicated that black bears use areas with higher primary productivity and fewer roads. The predictive performance of such models is rarely validated with independent data, so we validated our model predictions with 2-independent datasets. We first assessed the correlation between predicted and observed habitat use for 28 tele-metry-collared bears in the Jemez Mountains. Predicted habitat use was positively correlated with observed use for all 3 years (2012: ρ = 0.81; 2013: ρ = 0.87; 2014: ρ = 0.90). We then predicted the probability of use within a cell where a bear mortality was documented using 2043 mortality locations from sport harvest, depredation, and vehicle collisions. The probability of habitat use at a mortality location was also positively correlated with observed use by the species (2012: ρ = 0.74; 2013: ρ = 0.89; 2014: ρ = 0.93). Our validation procedure supports the notion that occupancy models can be an effective tool for estimating habitat use and predicting the distribution of highly-mobile species when the assumption of geographic closure has been violated. Our findings may be of interest to studies that are estimating habitat use for highly-mobile species that are secretive or rare, difficult to capture, or expensive to monitor with other more intensive methods.
... Killmaster, Georgia DNR-WRD, unpublished data). Since 1979, black bear populations have increased across north Georgia with annual growth rates ranging from 1.108 98 2018 JSAFWA to 1.113 (Little et al. 2017). Although, Georgia DNR-WRD lacks population trend data on bobcats and coyotes in north Georgia populations have purportedly increased over much of the eastern United States (Gompper 2002, Kilgo et al. 2010, Roberts and Crimmins 2010. ...
... Harvest of a female with cubs or any bear weighing <34 kg (live-weight) or use of bait was prohibited throughout the study period. Registration of harvested bears was mandatory and Georgia DNR-WRD personnel recorded data from all harvested bears including sex and weight (Little et al. 2017). Georgia DNR-WRD personnel also extracted a premolar for aging using cementum annuli (Willey 1974). ...
Most state wildlife agencies collect harvest data to inform management decisions. However, these data are typically considered across relatively short time periods and are rarely revisited. We present a case study using historical records to investigate potential agents (i.e., harvest, predation, and forest change) influencing the declining white-tailed deer (Odocoileus virginianus) population in the north Georgia mountains. We used long-term black bear (Ursus americanus) and deer harvest data, and indices of forest stand conditions from 1979-2015 on eight Wildlife Management Areas (WMAs) in the north Georgia mountains. During 1979-2015, harvest of male and female deer declined by 85% and 97%, respectively. Over the same time period, mean yearling male deer body weight increased by 21%, mean antler diameter increased by 62%, and mean antler beam length increased by 92%. We observed a 97% reduction in availability of early successional forests (0-10 years old) and a 53% increase in volume of large diameter (>27.9 cm) oak species, suggesting increasing homogeneity/maturation of forest stands across all eight WMAs. Concomitantly, the U.S. Forest Service increased the acreage under prescribed fire management from 2,916 to 5,629 ha during 2003-2015. Black bear populations grew at an annual rate of 1.07 for males and 1.08 for females. Our analyses indicated that despite the reduction in early successional habitats as illustrated by the reduction in young forests (0-10 years old), deer condition indices have improved suggesting that a habitat-driven change in fecundity was not the likely primary driver of the deer population decline. However, increasing fawn predation, coupled with a decline in available fawning cover may be reducing recruitment rates and should be investigated as potential causes for the observed population decline. Our research also illustrates the importance of maintaining long-term data, especially the value offered to evaluate trends over time.
Free-ranging large carnivores are involved in human-wildlife conflicts which can result in economic costs. Understanding factors that lead to human-wildlife conflicts is important to mitigate these negative effects and facilitate human-carnivore coexistence. We used a human-American black bear (Ursus americanus) conflict database maintained by the New York State Department of Environmental Conservation to determine whether drought, conflicts within the Adirondack and Catskill Parks as compared to outside of these parks, mild severity (Class 3) conflicts early in the year (April–June), and bear harvest in the previous year (as an index of bear abundance), were associated with greater frequency of high or moderate severity (Class 1–2) conflicts later in the year (July–September) across New York, USA. During 2006–2019, we obtained 3,782 mild severity conflict records early in the year, and 1,042 high or moderate severity records later in the year. We found that a one standard deviation increase in the cumulative precipitation difference from mean early in the year (about 7.59 cm) coincided with a 20% decrease in conflicts, and that Wildlife Management Units (WMUs) within the parks were predicted to have 5.61 times as many high or moderate severity conflicts as WMUs outside the parks. We also found that a one standard deviation increase in the frequency of mild severity conflicts (equivalent to 5.68 conflicts) early in the year coincided with an increase in the frequency of high or moderate severity conflicts in a WMU later in the year by 49%, while a one standard deviation increase in the bear abundance index in the previous year (0.14 bears/10 km2) coincided with a 23% increase in high or moderate severity conflicts. To reduce the frequency and severity of conflicts to facilitate human-black bear coexistence, we recommend the following measures to be taken in place consistently and build over time in local communities: (i) further reducing black bear access to anthropogenic foods and other attractants, (ii) non-lethal measures including bear-resistant waste management, (iii) electric fencing, and (iv) modifying placement or configuration of field crops.
