Suburban Deer Research Articles

Patterns of white-tailed deer movements in suburban Maryland: implications for zoonotic disease mitigation

AbstractUnderstanding the ecology of the often dense white-tailed deer populations in urban and suburban landscapes is important for mitigating a variety of conflicts that arise with dense human populations, such as issues surrounding zoonotic disease mitigation. We collared white-tailed deer in highly suburban areas of Howard County, Maryland with high-resolution GPS collars. Then, we created autocorrelated kernel density home ranges for broader land use analyses and concurrently used general additive models to characterize fine-scale hourly measures of speed, activity, and proximity to residential buildings. Suburban deer home ranges encompassed approximately 35% direct residential land, and an average of 71 and 129 residential properties were found within female and male core ranges, respectively. Sex, time of day, and day of year all influenced fine-scale speeds, activity levels, and proximity to residential property buildings. Deer moved into residential areas nightly, especially in winter, and exhibited bouts of increased speed and activity shortly after sunrise and sunset, with distinctive seasonal changes. We discuss how variation in home ranges and movements may influence population management success and explore year-round periods of increased risk of deer transporting ticks to residential areas. These findings focus our broad understanding of deer movements in suburban and urban landscapes to improve deer population management and to mitigate the spread of ticks into residential areas.

Ovariectomy As a Management Technique for Suburban Deer Populations

ABSTRACTOverabundant suburban deer (Odocoileus spp.) are a source of human‐wildlife conflict in many communities throughout the United States. Deer‐vehicle collisions, impacts to local vegetation, tick‐borne pathogens, and other negative interactions are typical reasons cited for initiating deer management programs. Social attitudes, legal constraints, and perceived safety concerns lead many communities to examine nonlethal management options. Surgical sterilization is currently the only nonlethal method available to permanently sterilize females with a single treatment. However, there are limited data demonstrating methods and outcomes in management programs that sterilize a high percentage (>90%) of local populations of females, particularly regarding the impact of immigration on non‐isolated populations. We present data from 6 surgical sterilization sites with geographically open populations in California, Maryland, Michigan, New York, Ohio, and Virginia, USA. From 2012 to 2020 we sterilized 493 deer, primarily via ovariectomy, and conducted annual or periodic population estimates using camera surveys, road‐based distance sampling, and intensive field observations to assess population trends. Study sites ranged from 1.2 km2 to 16.5 km2 with ~47–169 individuals, resulting in approximate densities of 6–63 deer/km2. For all sites we noted an average reduction of ~26% (17%–36%) from Year 1 to Year 2. Four years after initial treatment, we documented an average population reduction of ~45% (29%–56%). During the first year, the average cost per deer sterilized at locations where bait was used was US$1,185 ($927–$1,572). Surgical sterilization projects demonstrate that significant reductions in local deer densities using high‐percentage, surgical sterilization programs can be achieved in non‐insular locations, where baited deer are approachable by vehicle for darting. Sustained sterilization efforts may be necessary, as is the case with all deer management programs, in areas where immigration is possible, and all the animals are not sterilized. © 2021 The Wildlife Society.

Trapping White-Tailed Deer (Artiodactyla: Cervidae) in Suburbia for Study of Tick-Host Interaction.

Live capture of white-tailed deer (Odocoileus virginianus) (Zimmermann, 1780) is often necessary for research, population control, disease monitoring, and parasite surveillance. We provide our deer trapping protocol used in a tick-host vector ecology research project and recommendations to improve efficiency of deer trapping programs using drop nets in suburban areas. We captured 125 deer across two trapping seasons. Generally, lower daily minimum temperatures were related to increased capture probability, along with the presence of snow. Our most successful trapping sites were less forested, contained more fragmentation, and greater proportion of human development (buildings, roads, recreational fields). To improve future suburban deer trapping success, trapping efforts should include areas dominated by recreational fields and should not emphasize remote, heavily forested, less fragmented parks. Concurrently, our study illustrated the heterogeneous nature of tick distributions, and we collected most ticks from one trapping site with moderate parameter values between the extremes of the most developed and least developed trapping sites. This emphasized the need to distribute trapping sites to not only increase your capture success but to also trap in areas across varying levels of urbanization and fragmentation to increase the probability of parasite collection.

After Decades of Suburban Deer Research and Management in the Eastern United States: Where Do We Go From Here?

After Decades of Suburban Deer Research and Management in the Eastern United States: Where Do We Go From Here?

Suburban white-tailed deer seropositive for Toxoplasma gondii from Chicago, Illinois.

The presence and abundance of vertebrates influences the circulation of zoonotic diseases. White-tailed deer (Odocoileus virginianus) are widely distributed in North America and deer densities are frequently high in unhunted areas, including most major metropolitan regions. This study investigated the seroprevalence for Toxoplasma gondii from live-captured and culled deer sampled in two suburban forest preserves around Chicago, Illinois, from 1995 to 1999. Seroprevalence for T. gondii was 55.9% (n = 443) and was significantly higher at the northern study site, Des Plaines. Seroprevalence for T. gondii varied by year and month. Multivariate logistic regression (LR) screened main effect variables (age, sex, site, year, and month) by backward stepwise elimination. The final LR model for T. gondii contained all main effect variables. This study provides baseline data for future T. gondii suburban deer studies and information to public health and wildlife officials regarding the prevalence a parasitic pathogen present in two public forest preserves in Chicago, Illinois.

Fine‐scale spatial genetic structure of deer in a suburban landscape

ABSTRACTHunting regulations traditionally applied to manage deer populations in rural areas are not well suited to management in heavily populated suburban landscapes. We evaluated the spatial genetic structure of a suburban deer population to assess the feasibility of localized management at the scale of social groups. We used fecal DNA from white‐tailed deer (Odocoileus virginianus) in suburban Michigan to determine whether deer in suburban landscapes maintain the matrilineal social structure that has been observed in studies of rural deer. We amplified 7 microsatellite loci from fecal pellets (n = 591) collected from August to October 2013 on public and private lands throughout Meridian Township, Ingham County, central Michigan, USA. Based on multi‐locus genotypes, we identified individuals, quantified the extent of spatial genetic structure at multiple spatial scales, identified the location and spatial extent of aggregations of related females and males, and estimated genetic neighborhood size. We also used landscape genetic analyses to evaluate associations between measures of land cover, edge density, the presence of major roads, and inter‐individual genetic distance. Spatial genetic autocorrelation was positive and significant up to a distance of 0.5 km. We did not detect correlations between landscape variables and inter‐individual genetic distance. Results indicate that deer in suburban landscapes exhibit familial structure reported for deer in more rural areas, albeit at a smaller spatial scale, and with substantial overlap among groups. Management at the spatial scales of genetically related groups of deer may be feasible in suburban communities. © 2018 The Wildlife Society.

Cost-benefi t analysis of managed shotgun hunts for suburban white-tailed deer

Deer managers often utilize managed hunts to curtail burgeoning white-tailed deer (Odocoileus virginianus) populations in suburban areas. Although several studies have used population modeling to focus management, these efforts generally provide only harvest numbers, without considering the spatial placement of hunters on the landscape. Further, few studies have modeled management effort as deer density changes during the hunt. We modeled 2 types of managed shotgun hunts, a replacement hunt, where the stand of each successful hunter would be fi lled the following day, thus, ensuring the same number of hunters would be present each day of the hunt, and a non-replacement hunt, for Southern Illinois University-Carbondale. We modeled population growth of deer and numerical response to harvest to 25%, 50%, and 75% reduction levels. We used a GIS to determine potential hunter numbers and their placement on the landscape. We then used data from the literature to model optimal season length and to estimate the costs and benefi ts of the 2 managed shotgun hunt types. The non-replacement hunt was less expensive overall and had a lower cost per day, but the replacement hunt was more cost-effi cient in terms of deer harvested and could meet higher population reduction goals. Our study illustrates the importance of considering cost, hunter placement, and effort prior to conducting a managed shotgun hunt for suburban deer.

Sterilization as an alternative deer control technique: a review

Burgeoning white-tailed deer (Odocoileus virginianus) populations in suburban landscapes continue to impact communities and challenge natural resource managers. Increased deer-related damage to vegetation, ecosystems, and automobiles can exceed the tolerance of local stakeholders. We provide an overview of the potential effi cacy of using surgical sterilization to help manage populations and confl icts associated with locally overabundant white-tailed deer populations. We review theoretical and fi eld studies pertaining to deer sterilization, and provide research priorities to help guide future sterilization efforts. Recent fi eld studies suggest that sterilization of female deer remains expensive, at approximately $1,000 per surgery. Sterilization may provide an alternative management technique for reducing suburban deer herds in communities willing to endure the costs of a long-term effort and where lethal deer removal is unacceptable or impractical. Surgical sterilization is scale-limited based on the ability to capture and sterilize 80% or more of the female deer in a population and maintain that proportion of the population treated over time. Overall success will be greatest for closed or insular deer herds where the effects of immigration can be minimized.

Perceived and desired outcomes of suburban deer management methods

ABSTRACTDisparity among natural resource agencies and the public often arises when white‐tailed deer (Odocoileus virginianus) are managed in suburban areas. To resolve conflicts, managers require information as to why public constituents deem deer management methods acceptable. We surveyed 660 residents in a suburban Illinois county to evaluate attitudes toward 5 deer management methods: archery hunts, gun hunts, sharpshooting, fertility control, and no management. We used the expectancy‐value model to determine beliefs and desires regarding outcomes of deer management methods that drove respondent acceptance and rejection toward deer management regimes. We then used multinomial logistic regression models to determine which public beliefs and desires regarding outcomes of each deer management method predicted acceptance of each method. Attitudes of respondents who accepted and rejected each deer management method differed from respondents who were neutral toward the methods (F2,215 = 3.59–17.93; 0.001 ≥ P ≤ 0.029). The variables most influencing beliefs toward lethal methods regarded whether deer will suffer an inhumane or unnatural death due to the management method (Akaike relative weight ω ≥ 0.95). Beliefs that damage to personal property from deer will decrease drove the acceptance of archery hunts and professional sharpshooting (ω ≥ 0.95). Beliefs regarding the number of deer‐vehicle collisions decreasing and deer dying an unnatural death had the strongest support for predicting a person's acceptance or rejection of fertility control (ω = 0.98). The desire for a low‐cost management technique and deer numbers to remain the same or increase were the strongest predictors for accepting no deer management (ω = 0.96). Although the expectancy‐value model offers the framework to identify attitudinal disparities among citizens who accept and reject deer management methods, not all of the variables in each model set provided further information on why attitudes toward each deer management method differed among residents. Understanding respondent beliefs and desires regarding outcomes of deer management methods will ultimately allow managers to guide education, resolve some management disputes, and aid in future management decisions that may increase the effectiveness of a deer management regime. © 2015 The Wildlife Society.

Influence of landscape factors on density of suburban white-tailed deer

Resource management agencies and urban planners require information from large-scale assessments of factors affecting suburban white-tailed deer (Odocoileus virginianus) density to guide deer management and urban development. We assessed the influence of landscape factors on density of suburban deer on 40 forest preserves in northeastern Illinois during 1999–2002. We created candidate model sets for 3 spatial scales: preserve (15–1238ha; 29 models), buffer-only (132–1335ha; 24 models), and total area (147–2322ha; 33 models). We selected models using AICc and obtained 3–10 top models for each model set which constituted 50–89% of the Akaike weights. Using supported variables in these model sets, we created a new final model set (35 models) in which 8 models contributed to 95% of the top Akaike weights. Patch density of agricultural land within preserve borders (ω=0.95; β′=0.47), the mean nearest neighbor distance between all cover patches within preserve borders (ω=0.95; β′=0.38), the diversity of patch types within preserve borders (ω=0.66; β′=−0.24), and the percent core area of forested land within preserve borders (ω=0.52; β′=0.21) were the strongest predictors of suburban deer density. Natural resource managers should limit agricultural practices, reduce core areas of forest patches, and increase diversity of land cover patches within preserve borders to potentially reduce deer densities and limit deer population growth.

Determinants of Public Perceptions of Suburban Deer Density

As deer management activities increase in developed areas, managers require information regarding which factors contribute to deer acceptance capacity. We surveyed Illinois residents in a suburban county where deer have been proactively managed since 2001 to determine respondent characteristics and perceptions, beliefs, and feelings regarding deer that contribute to public perceptions of deer density. Almost half of the respondents perceived the number of deer as “perfect.” We used polytomous regression with AICc model selection to identify variables that contributed to a respondent's perception of deer density. The most parsimonious model (AICc ω = .97) indicated a respondent's perception of changes in deer density, damage to personal property, and the respondent's general feelings regarding deer drove the perceptions of too many or too few deer (as opposed to the perfect number). This article exemplifies the complexity of deer acceptance capacity and aids managers in understanding public perceptions regarding suburban deer density.

Policy learning and deer co‐management in New York State: Insights from newspaper coverage

AbstractResolution of urban and suburban deer problems often depends on learning and co‐management. Local newspapers may reflect the learning occurring in a community. Past authors have identified 4 primary types of learning (technical, conceptual, social, and political). We studied newspaper content related to deer management for insights about the types of learning occurring in selected regions in New York State. We analyzed 263 newspaper articles published between 2000 and 2006. We found that the majority of content related to learning focused on conceptual and technical learning, but relatively little, particularly early in the evolution of deer management issues, focused on social or political learning. Our results suggest that additional attention to social learning focusing on collaborative relationships and constructive dialogue among stakeholders by both communities and newspapers could be beneficial in the resolution of deer problems. © 2012 The Wildlife Society.

Deer, Humans, and Vegetation: A Case Study of Deer Management in the Chicago Metropolitan Area

Many natural resource agencies are managing white-tailed deer populations in suburban areas and require information about deer populations, deer impacts on vegetation, and human preferences toward deer and deer management to support decision making. We utilized a multi-faceted approach to investigate common obstacles in suburban deer management and discuss findings from our study based in the Chicago Metropolitan Area during 2007-2011. We discuss the need for managers to examine suburban deer populations and management issues at a broader scale (i.e., countywide versus single community) and promote proactive deer management in lieu of the conventional paradigm of beginning management only when deer populations have become overabundant. Discussion topics include practicality and costs of deer density estimation and herbivory monitoring techniques over multiple plant communities and numerous study sites. In addition, we illustrate how a comprehensive human dimensions survey can identify determinants that contribute to the public’s perceptions of deer density and assess the acceptability, conflict, and beliefs regarding deer management methods. Lastly, we describe the relationship between landscape characteristics and deer density; this information can be utilized to determine suburban lands that may be prone to high deer densities and inform land management practices. Our work provides suburban natural resource managers with techniques to identify management practices supported by their public constituents and information useful for managing deer populations.

Urban and suburban deer management by state wildlife‐conservation agencies

AbstractGiven an increase of white‐tailed deer (Odocoileus virginianus) populations in many urban and suburban areas, deer management has become increasingly controversial. We surveyed deer biologists at state conservation agencies to compare opinions regarding urban and suburban deer management with those found in public surveys. We emailed a survey to deer biologists in 41 states to investigate what agencies are doing to control urban deer, which management techniques have been used in the past and are currently being used, and which techniques are believed to be most effective. Urban and suburban deer populations were increasing in most states (75.8%); accordingly, most biologists (97%) believed that urban and suburban deer were a problem in their state. Sixty‐five percent of biologists have not surveyed local communities for their opinions on deer and deer management. Managed archery hunts (85% of states), sharpshooting (68%), and managed firearm hunts (59%) were the most utilized methods during the past 5 years. Biologists ranked managed firearm hunts (54%) as the most preferred method for deer control, followed by managed archery hunt (39%) and sharpshooting (39%). Ninety‐one percent of biologists listed deer–vehicle accidents and damage to gardens as primary reasons for managing urban deer populations. Most biologists (88%) indicated that urban and suburban deer management in their state was overall effective. Biologists and public constituents agree on the primary reasons to manage deer, yet their preferences for management options vary greatly. We recommend state agencies survey constituents regarding their beliefs and concerns about deer management beyond questions that simply address the acceptability of management techniques. © 2011 The Wildlife Society.

Overabundant suburban deer, invertebrates, and the spread of an invasive exotic plant

AbstractWhite‐tailed deer (Odocoileus virginianus) overabundance is a problem of serious concern for wildlife managers. At densities as low as 8 deer/km2, changes in vegetation due to deer feeding patterns have been demonstrated to negatively impact other wildlife species. The Middle Patuxent Environmental Area (MPEA) in Howard County, Maryland, USA, currently supports a deer population of approximately 41 deer/km2. We used an experimental approach to examine how deer overabundance in a suburban environment impacts both vegetation and invertebrates. Ten 20‐m × 20‐m deer exclosures were constructed in the MPEA during the winter–spring of 1999. Vegetation and invertebrate data have subsequently been collected inside the exclosures and areas adjacent to the exclosures (control) during the summers of 1999, 2003, and 2007. There was no initial difference in vegetation variables between exclosure and control plots in 1999 (P > 0.05). Post‐1999, plant species richness was greater in the exclosure than in the control. A multivariate analysis of variance revealed differences (P < 0.001) in vegetation cover variables between exclosures and controls, with a greater percentage of forbs, shrubby vegetation, and taller stems in the exclosure and more grass and exotics in the control. There were few differences in invertebrates between exclosures. The differences observed in vegetation between exclosures is believed to reflect interactions between deer feeding patterns and the invasive Japanese stilt grass (Microstegium vimineum) and unless deer density is reduced, it is likely that the exotic Japanese stiltgrass will continue to increase in abundance and native plant species will decrease. © 2011 The Wildlife Society.

Examining the potential of community design to limit human conflict with white‐tailed deer

AbstractModification of habitat has the potential to be both less costly and less controversial than direct management of white‐tailed deer (Odocoileus virginianus) populations in addressing problems related to suburban deer overabundance. A novel approach to reducing deer–human conflict would involve anticipating issues of deer management when communities are designed. We tested the hypothesis that the compact character of traditional neighborhood designs will result in reduced habitat suitability for deer as compared to suburban‐sprawl patterns of development. We evaluated landscape pattern and estimated deer densities in 2 communities in upstate New York, USA, and then predicted habitat condition and potential deer densities in different types of development. Comparisons of the habitat conditions in the neighborhood versus sprawl areas revealed significant differences in the amount of edge between the tree and lawn class (P < 0.05), with sprawl development having a greater tree–lawn edge density. Both field and tree disjunct core‐area densities were significantly higher in areas of sprawl development (P < 0.01). Increasing amounts of field and the distribution of tree canopy across the landscape were associated with increased deer densities. In the suburban environment, where food is abundant, the availability of cover throughout the landscape becomes an important factor affecting deer density. © 2011 The Wildlife Society.

The sustainability of controlled archery programs: The motivation and satisfaction of suburban hunters

AbstractOver the last decade, wildlife professionals in the New York City (NY, USA) metropolitan area have increasingly turned to controlled archery hunts to reduce overabundant suburban deer populations. The success of these deer management programs (DMPs) depends on a willing pool of hunters motivated to meet harvest goals. This requires maintaining hunter satisfaction both now, and in the future when successful herd reduction will result in fewer opportunities for deer harvest. With the goal of providing local deer managers with feedback from hunters partaking in DMPs, we used surveys designed to evaluate why members hunted, why they joined DMPs, members' views on deer management, and ultimately, their satisfaction with controlled hunts. Members were primarily motivated to hunt by the chance to see wildlife, opportunities for recreation, and a passion for archery. Most (71%) reported that their enjoyment had increased since first joining a DMP and satisfaction was not linked to harvest opportunity or success. Nevertheless, we documented several trends that threaten the long‐term sustainability of DMPs. First, 78.2% of survey respondents were over the age of 40, possibly suggesting fewer younger recruits into DMPs. Second, the opportunity to hunt previously unhunted land, a transitory incentive, was the most common reason for participating in DMPs. Third, respondents whose DMP doe harvest was limited by choosing to spend time on private, non‐DMP land were also more likely to have seen fewer deer on DMP lands (G‐test = 13.2, df = 4, P = 0.01). This suggests that effort will decline as deer herds decline. © 2011 The Wildlife Society.

Behavior and survival of white-tailed deer neonates in two suburban forest preserves

Neonatal survival influences growth of unhunted populations of suburban white-tailed deer ( Odocoileus virginianus (Zimmerman, 1780)). Understanding the interaction of habitat and survival may inform conservation efforts and studies of life history of cervids at high density. We chose two forest preserves representative of forests in suburban Chicago. We radio-marked 56 neonates (1999–2001) to investigate mortality and habitat use. Through 1 July, 21 of 29 (72%) neonates and 6 of 22 (27%) died mostly because of predation by coyotes ( Canis latrans Say, 1823). Akaike’s information criterion suggested that optimal mark–recapture models of survival contained covariates reflecting differences by preserve and timing chosen to coincide with behavioral change from hiding to accompanying the doe. Survival was lower during early parturition (0.26–0.78) relative to the latter part (0.90–0.96). Early fawns (hiders) at one site had lower survival (0.26–0.29) than fawns at the other (0.78). Lower survival associated with larger home ranges, greater movement, and reduced understory cover, suggesting that hiding cover may mediate fawn survival in the presence of predators. Our study demonstrates spatial heterogeneity in population biology of suburban deer and suggests that site-specific differences may influence neonate survival in the face of coyote predation.

The Tragedy of Becoming Common: Landscape Change and Perceptions of Wildlife

Some wildlife species are adapting to urbanizing settings made more attractive due to changes in land-use practices, human attitudes and behaviors, and conservation efforts. People who live in communities near suburban parks are encountering wildlife more frequently than in the past, with varying reactions. In-depth interviews conducted with residents living near three national parks yielded insight on “suburban deer” as an emerging social construct. Interviewees described expectations about deer abundance and behavior that guided their interactions with suburban deer and affected deer behavior, which in turn affected interviewees’ evaluations of deer and subsequent responses to interactions. Left unchecked, this process may result in the ultimate “tragedy of becoming common,” when species are no longer viewed as wildlife, but as pests or pets. In the absence of an established cultural construct for suburban wildlife, stakeholder engagement will continue to play an important role in understanding and addressing these diverging views.

Space Use and Survival of White‐Tailed Deer in an Exurban Landscape

Abstract: Exurban development is nonmetropolitan, residential development characterized by a human population density and average property size intermediate between suburban and rural areas. Although growth in exurban areas is outpacing that of urban, suburban, or rural landscapes, studies of deer (Odocoileus spp.) ecology in exurban areas are nonexistent. During 2003–2005, we studied space use (i.e., seasonal home‐range and core‐area size and habitat use relative to human dwellings) and survival of 43 female white‐tailed deer (O. virginianus) in an exurban setting near Carbondale, Illinois. Deer had larger home ranges than most suburban deer populations and generally smaller home ranges than rural deer populations. When we analytically controlled for habitat use, deer exhibited a subtle avoidance of human dwellings, especially during the fawning season. The annual survival rate was among the highest reported in the literature at 0.872 (SE = 0.048). Only 5 deer (cause‐specific mortality rate = 0.091) were harvested by hunters, indicating major obstacles for wildlife managers when attempting to manage deer in exurban areas using traditional hunter harvest.