Deer Management Research Articles

Strengthening urban deer management with structured decision making

Urban deer management (UDM) decision‐makers face social, ecological, regulatory, and economic pressures when creating an agreeable deer management plan for stakeholders. Historically, decision making techniques (e.g. consensus‐based analyses) have not effectively balanced UDM elements leading to short‐lived management progress. Structured decision making (SDM) is a formal, values‐based approach to identifying an optimal management solution. Although SDM has been applied to other wildlife management decisions, it has not been applied in UDM. We provide the first case‐study of SDM‐based UDM and streamline the process for wildlife managers. We focused on one suburban and one semi‐rural community near Atlanta, Georgia, USA. We established a problem statement to capture what decision‐makers must address in UDM programs and reviewed the primary literature and UDM plans from five states to establish four fundamental objectives. We then utilized a support–effectiveness analysis to identify acceptable UDM alternatives and gathered expert insights to calculate the consequences of alternatives on objectives. Finally, we asked each community's decision‐makers to weigh objectives against each other. Using this framework, education was the most optimal UDM technique to implement in the suburban community, and sharpshooting was the most optimal UDM technique to implement in the semi‐rural community. This paper positions SDM as a transparent, defensible, inclusive, and adaptive approach to UDM. Furthermore, our SDM framework provides managers with the means and justification to create an optimal plan of action for communities in need of UDM.

Comparison of thermal cameras and human observers to estimate population density of fallow deer (Dama dama) from aerial surveys in Tasmania, Australia

Context The population of introduced fallow deer (Dama dama) is thought to have increased exponentially across much of the island of Tasmania, Australia, since 2000. Historically, deer management decisions have relied on population trend data from vehicular spotlight surveys. Renewed focus on the contemporary management of the species requires development of more robust and precise population estimation methodology. Aims This study demonstrates two aerial survey methods – conventional counts by trained human observers, and thermal imaging footage recorded during the same flights – to inform future survey practices. Methods Conventional counts were carried out by three observers, two seated on the left side of the helicopter, and one on the right. A high-resolution thermal camera was fitted to the helicopter and was orientated to meet the assumptions of distance sampling methodologies. Both survey methods were used to generate deer population density estimates. Spatial distribution of deer was also analysed in relation to patches of remnant native vegetation across an agricultural landscape. Mark–recapture distance sampling was used to estimate density from human observer counts and provide a comparison to the distance sampling estimates derived from the thermal camera. Key results Human observer counts gave a density estimate of 2.7 deer per km2, while thermal camera counts provided an estimate of 2.8 deer per km2. Deer population density estimates calculated via both methods were similar, but variability of the thermal camera estimate (coefficient of variation (CV) of 36%) was unacceptably high. Human observer data was within acceptable bounds of variability (CV, 19%). The estimated population size in central and north-eastern Tasmania for 2019 approximated 53,000 deer. Deer were primarily congregated within 200 metres of the interface between canopy cover and open pasture. Conclusions The population density estimate provides a baseline for monitoring and managing the Tasmanian deer population. Human observer data was more precise than thermal camera data in this study, but thermal counts could be improved by reducing sources of variability. Implications Improvements for the collection of thermal imagery are recommended. Future control efforts may be more efficient if they preferentially target habitat edges at this time of year, paired with random or grid-based searches where population density is lower.

Site fidelity trumps disturbance: aerial shooting does not cause surviving fallow deer (Dama dama) to disperse

Context Aerial shooting is an important tool for managing the economic and environmental impacts of widespread wild fallow deer populations in eastern Australia and could be crucial for mounting an effective response to an emergency animal disease incursion. However, there is a concern that the disturbance caused by aerial shooting could cause infected animals to disperse, thereby transmitting pathogens to previously uninfected areas. Aims We sought to describe the nature and extent of spatial behavioural changes in fallow deer exposed to aerial shooting to: (1) assess the risk that aerial shooting poses to disease spread, and (2) better understand how aerial shooting can contribute to routine deer management programs. Methods We contrasted movement rates, activity range areas, and daily activity patterns of 48 GPS-collared fallow deer before, during and after exposure to aerial shooting at three sites in New South Wales. Key results No collared deer left its pre-shoot activity range area during shooting or within 30 days after shooting finished. Observed behaviour changes included increased daily and hourly distance travelled by female deer during and after shooting, increased activity range areas for female deer after shooting, and increased nocturnal activity in female and male deer during shooting. However, observed changes were minor, temporary, localised, and variable among sites. Conclusions Collared deer showed strong site fidelity despite repeated intense disturbance and substantial population reductions. We found no evidence to support concerns that aerial shooting poses a hazard of disease spread. Implications Aerial shooting should be retained as a key control tool for managing wild fallow deer populations in Australia, including for reducing disease host population densities in the event of an emergency animal disease incursion.

Whole-Genome Analyses Reveal the Distinct Taxonomic Status of the Hainan Population of Endangered Rucervus eldii and Its Conservation Implications.

Eld's deer Rucervus eldii (McClelland, 1842) is an ungulate that lives in tropical lowland forests in several countries of Indochina and Hainan Island of China. Its remaining population is small and scattered, and the species is listed as an Endangered species on the IUCN Red List. The debate over the taxonomic status of the Hainan population has persisted for over a century-as an island-endemic subspecies R. e. hainanus, or an insular population of the subspecies R. e. siamensis, would have significant conservation implications. And, given the Hainan population had experienced both population bottleneck and multiple translocations in the past, conservation genomics would be a powerful tool to evaluate the genetic impacts of these events. In this study, we used conservation genomics assessment to study population differentiation and genetic diversity of R. e. siamensis in Cambodia and three Eld's deer subpopulations on Hainan Island. Based on the unique genetic profile and demographic analysis, this study corroborated previous studies using genetic markers that the Hainan Eld's deer warrants the taxonomic status of a distinct subspecies. The Hainan population exhibits a reduction in genetic diversity and an increase in the level of inbreeding when compared to the population of Cambodia. The signs of purifying selection were found against homozygous loss-of-function mutations to decrease the deleterious burden in the Hainan population. However, there was an accumulation of more deleterious missense mutations. Furthermore, significant differences in genetic diversity and level of inbreeding found among the three Hainan subpopulations indicated population isolation and suboptimal translocation strategies, which calls for urgent, coordinated, and science-based genetic management to ensure the long-term viability of the endemic subspecies hainanus. This study provides guidance for the conservation and management of Eld's deer.

Probiotic Potential of Lactobacillus and Enterococcus Strains Isolated From the Faecal Microbiota of Critically Endangered Hangul Deer (Cervus hanglu hanglu): Implications for Conservation Management.

The mammalian gut microbiota plays a crucial role in promoting host health, and lactic acid bacteria (LAB) are commonly employed as probiotics for their beneficial effects. The Hangul deer (Cervus hanglu hanglu), a critically endangered red deer subspecies found in the Indian subcontinent, requires meticulous health management for its conservation. This pioneering study aimed to isolate, identify, and evaluate the in-vitro probiotic functional properties of LAB strains from the faeces of Hangul deer. A total of 27 LAB strains were isolated and identified using 16S rDNA gene sequencing, followed by comprehensive probiotic characterization and safety assessment. Remarkably, four species exhibited robust resistance and survivability against varying pH levels and bile salts, along with high aggregation and co-aggregation capacities. Notably, Lactobacillus acidophilus and Enterococcus mundtii strains displayed antibacterial activities. Safety assessment revealed the absence of hemolytic activity and virulence genes in all four strains. Antibiotic susceptibility testing showed that Lactobacillus acidophilus and Enterococcus casseliflavus were susceptible to all tested antibiotics, while Enterococcus mundtii exhibited resistance to clindamycin, and Enterococcus gallinarum exhibited resistance to erythromycin. These findings suggest that the isolated LAB strains possess advantageous probiotic characteristics and hold potential as dietary supplements for promoting the health and disease management of Hangul deer.

Patterns of Hemorrhagic Disease in White-Tailed Deer (Odocoileus virginianus) in the Great Plains of the USA, 1982-2020.

Hemorrhagic disease (HD) of deer is caused by epizootic hemorrhagic disease virus (EHDV) or bluetongue virus (BTV) and is considered one of the most important viral diseases of white-tailed deer (Odocoileus virginianus). Despite evidence of changing patterns of HD in the northeastern and upper midwestern US, the historical and current patterns of HD in the Great Plains remain poorly described. We used results from an annual survey documenting HD mortality to characterize historic and current patterns of HD in the northern and central Great Plains (North Dakota, South Dakota, Nebraska, Kansas, and Oklahoma), US, between 1982 and 2020. Further, we assessed temporal change using linear regression to determine change in annual reporting intensity (percentage of counties in a state with reported HD) and change in reporting frequency (the number of years a county or state reported HD) during each decade between 1982 and 2020. Across the 38-yr study period, HD reports expanded northeast across latitude and longitude. Intensity of HD reports significantly increased during this period for three (North Dakota, South Dakota, Kansas) of five states examined. Frequency of reports also increased for all five states. Such changes in northern latitudes might lead to increased deer mortality in regions where HD epizootics have been historically less frequent. Understanding how patterns of HD are changing on the landscape is important when considering future deer management in the face of other mortality factors.

Comparison and association of winter diets and gut microbiota using trnL and 16S rRNA gene sequencing for three herbivores in Taohongling, China

Food provides essential nutrients and energy for wildlife and directly influences the compositional patterns of the gut microbiota in natural reservoirs. Little is known about the interspecific differences and correlations between diet and microbial communities in sympatric herbivores. We conducted chloroplast trnL and 16S rRNA genes amplicon sequencing of 90 faecal samples from sika deer (Cervus nippon kopschi), Reeve’s muntjac (Muntiacus reevesi), and a Chinese hare (Lepus sinensis). Diet analysis revealed that sika deer predominantly foraged on Rubus (36.5 %), Loropetalum (25.5 %), and Eurya (13.4 %) at the genus level; Reeve’s muntjac favoured Rubus (51.8 %), Eurya (11.0 %), and Euonymus (6.1 %); Chinese hare showed dominance in Rubus (15.8 %), Smilax (15.6 %), and Rhus (10.6 %) consumption, with all these forage plants being shrubs. The gut microbiota of the three herbivores was characterised by Firmicutes, Bacteroidetes, and Proteobacteria, although the relative abundances of these taxa differed across herbivore species. Alpha diversity indicated no significant differences between sika deer and Reeve’s muntjac, whereas alpha indices showed significant differences between sika deer and Chinese hare (p < 0.05). Beta diversity analysis indicated significant differences between the Chinese hare and sika deer, as well as between the Chinese hare and Reeve’s muntjac (p < 0.05), with no significant difference found between the two cervid species, which may be attributed to the influence of interspecific genetics and evolutionary factors. Due to seasonal shifts, the food availability for herbivores decreased, resulting in the convergent adaptation of shrubs consumed by the three species. Furthermore, PICRUSt functional profile prediction indicated that the gut microbiota of the three species were mainly enriched in metabolic functions. Mantel correlation analysis suggested that the gut microbiota of sika deer showed a significant positive correlation with five genera of plants, one genus of Reeve’s muntjacs, and three genera of Chinese hare (p < 0.01), suggesting that the gut microbiota of sika deer may be more susceptible to changes in food abundance. Our study emphasises how the winter climate affects the foraging strategies and microbial communities of the three herbivores, as well as their correlations. These results may further contribute to the food selection, regulation of gut microbiota, disease prevention, conservation, and management of sika deer and other sympatric herbivores.

Temporal habitat use of mule deer in the Pueblo of Santa Ana, New Mexico

AbstractMule deer (Odocoileus hemionus) are important economically, culturally, and recreationally to the Pueblo of Santa Ana in central New Mexico, USA. Studies of habitat selection improve our understanding of mule deer ecology in central New Mexico and provide the Tribe with valuable information for management of mule deer. We used global positioning system telemetry‐collar data collected on mule deer around the Pueblo of Santa Ana to create resource selection functions from proximity‐based habitat predictors using a generalized linear mixed model. We created separate resource selection functions for females and males during summer and winter at different times of the day. Season generally had a greater effect on mule deer habitat use than the time of day. Female and male mule deer selected for similar habitats but were sexually segregated in their summer distributions. These findings are consistent with results from other locations where mule deer partitioned habitat similarly between seasons and sexes. Supported models reaffirm accepted patterns of habitat selection for mule deer to the Pueblo of Santa Ana where local results were lacking. Our results can help managers identify locations in and around the Pueblo of Santa Ana where future development such as highway expansion are likely to conflict with mule deer activity and locations where habitat enhancement projects such as adding water sources can have the greatest effect for the deer population.

Deerly departed: Using motor-vehicle accidents to determine factors influencing white-tailed deer rut timing in Ontario, Canada

In seasonal environments conception is timed such that offspring are born at the peak of resource abundance. Although largely determined by photoperiod, reproductive timing can also be modulated by fluctuating environmental conditions. Some studies show that reproduction is occurring earlier, coinciding with an earlier spring as the climate warms. A failure to synchronize parturition with the advancing spring flush of resources can lower reproductive fitness; on the other hand, a longer growing season could be beneficial to some species. We asked whether breeding phenology of white-tailed deer (Odocoileus virginianus) has changed with changing environmental conditions. Using 29 years of wildlife motor-vehicle accident data (1988–2016) as an index of deer rut behaviour in southern Ontario, Canada, we assessed four deer management areas (DMAs) to determine: 1) whether timing of the white-tailed deer rut has changed; 2) whether the growing season has changed; and 3) whether changes in growing season and rut are correlated. We found that in the southwestern-most DMA the peak of the rut is 9 days earlier than in the northeastern-most DMA. The peak of the rut did not change over three decades. We detected an increase in the number of growing degree days, signifying both an earlier start to spring green-up and a later end to fall. The trend toward a longer growing season could have positive impacts on deer populations throughout the province.

Modelling the spatial abundance of invasive deer and their impacts on vegetation at the landscape scale

Deer populations and their impacts on forest ecosystems are increasing globally. Given the imperative and expense to mitigate impacts of invasive deer, we aimed to elucidate critical drivers of (i) deer density, (ii) deer impacts, and (iii) the relationship between them, to facilitate targeted management. We used quantile regression forests to model deer density (faecal pellet counts at 1948 locations) and impacts (browsing and other impacts on > 23,000 woody plants at 343 locations) across a mosaic of agricultural and forested ecosystems in Victoria, Australia (12,775 km2). Climate, topography, vegetation cover, and distance to water features were included as model covariates. Modelled deer density (r2 = 0.71, MAE = 0.56 pellets/m2) was most influenced by distance to waterbodies (> 10 ha, 31.2%), elevation (14.3%) and woody vegetation cover (12.9%). Modelled deer impact (r2 = 0.32, MAE = 6.9%) was most influenced by deer density (21.0%), mean annual precipitation (12.8%) and elevation (12.2%). Deer density was typically highest near large waterbodies, at low elevation, and with intermediate tree cover (40–70%). Impacts increased steadily with deer density up to ~ 2 pellets/m2. Our study demonstrates the importance of forest water and forest agricultural interfaces for both deer density and impacts. Deer are likely to be most abundant near waterbodies due to the availability of high-quality forage and water, and prefer lowland locations that have access to both open and forested habitats. Spatial models can be used to predict deer density and associated impacts to facilitate targeted invasive deer management.

Mapping social conflicts to enhance the integrated management of white‐tailed deer (Odocoileus virginianus)

AbstractUnderstanding the social feasibility of wildlife conservation approaches is essential to reducing social conflicts over wildlife and public backlash toward wildlife agencies and organizations. The Potential for Conflict Index2 (PCI2) and geospatial analyses of conflict can help wildlife practitioners strategically engage their publics, but these two tools have yet to be combined. Using data from a 2021 survey about white‐tailed deer in Indiana (n = 1806), we analyzed conflict levels among stakeholder self‐identities and political ideologies regarding the acceptability of six possible management methods, three lethal and three nonlethal. We then conducted a hotspot analysis of gridded PCI2 values to map areas of high and low social conflicts across the state. Conflict potentials showed more consistent covariation with political ideologies than with stakeholder self‐identities, aligning with urban–rural divides in wildlife experiences. Data on political leanings and residency may thus be more reliable than stakeholder categories to predict social conflicts over wildlife management. Hotspots of conflict over lethal methods clustered around urban areas, indicating that agencies should focus on engaging urban residents about deer management. Our conflict hotspots can be combined with other spatial data to create social units of analysis, which can help practitioners develop targeted and socially accepted strategies for wildlife conservation and management.

Aspect of feeding management for Sambar deer (Cervus unicolor) in Universitas Sumatera Utara park

This study aims to determine the management of animals in sambar deer captivity in terms of the aspect of feeding. The purpose of this study was to determine the management of sambar deer in terms of feeding techniques. This research was carried out in August - September 2022 using the observation method at the University of North Sumatra Park. The research data were obtained from the results of interviews with the animal keeper, data were analyzed using descriptive analysis. Data were calculations carried out regarding feed consumption and feed preferences for Sambar deer. The results showed that the management of the hopeful sambar deer in terms of the aspect of feeding at the North Sumatra University Park could be categorized as good in terms of the type and amount of feed that was sufficient to meet the basic needs of the animals. The average feed consumption reaches 4.8 kg/day/head. The most preferred type of feed is carrots (Daucus carota L) with a preference level of 21%. Further research is needed regarding the feeding of sambar deer according to the needs of their physiological status.

Acuan Praktik Terbaik Dalam Pengembangan Penangkaran Rusa Timor

Knowing the problems in captivity is very important for the management so that these problems can be resolved properly, and the management can anticipate so that problems do not occur again. Therefore, this research aims to examine the management of Timor deer breeding in each different breeding unit and formulate breeding management as a reference for best practices in the development of Timor deer breeding. The analysis used in this research is descriptive analysis. Descriptive analysis is used to describe data from observations and interviews which include housing aspects, feed aspects, health and care aspects, as well as data and information aspects. Based on the research results, it shows that breeding management of Timor deer requires a holistic approach that includes aspects of housing, feeding, health and population management. Choosing the right location, good cage structure planning, adequate feed availability, effective health care, and wise population management are the keys to a successful captive breeding program. An organized recording system and collaboration with related parties also supports the sustainability of the Timor deer breeding program.

Regional differences in deer hunter attitudes and opinions regarding quality deer management (QDM)

ABSTRACT Quality deer management (QDM) is the preeminent framework by which white-tailed deer are managed in the eastern USA. Historic differences surrounding the cultures, traditions, and regulations of deer hunting exist regionally between the Midwest and Southeast, yet no published study has investigated regional differences in attitudes and opinions of QDM among deer hunters. We surveyed 9,301 deer hunters across two Midwestern states (Missouri and Ohio) and two Southeastern states (Louisiana and South Carolina) and found that hunters across regions held similar motivations for deer hunting, as well as similar attitudes and opinions of strategies and expected outcomes of QDM. However, there existed several mismatches between the practices and ideology associated with QDM among Southeastern hunters. Southeastern hunters held greater support for greater antlered bag limits, protection of does, and supplemental feeding. We postulate that these mismatches are largely driven by regional differences in cultures, traditions, and regulations surrounding deer hunting.

Wild game processors’ perceptions of chronic wasting disease risks in Michigan

ABSTRACT Chronic wasting disease (CWD) is a neurodegenerative disease that threatens deer population health and management. This qualitative study explored processors’ perception of CWD risks, and the solutions or barriers they experience regarding managing these risks. Processors can play a critical role preventing consumption of CWD-positive venison by keeping CWD-positive deer out of facilities and implementing practices that minimize the risk of cross-contamination should CWD-positive deer enter facilities. Our analysis of semi-structured interviews of wild game processors found that they are concerned about CWD but have not altered processing practices, believing that most of the responsibilities for preventing CWD spread lie with hunters. Processors suggested several practices that state regulatory agencies can implement to aid in efforts to ensure that no CWD-positive deer enter facilities. This research may inform state agencies’ CWD communication efforts and identify actionable policies that better ensure processors can help prevent the consumption of CWD-positive venison.

Landscape structure does not hinder the dispersal of an invasive herbivorous mammal in the New Caledonian biodiversity hotspot

Biological invasions are a major threat to biodiversity and have particularly devastating impacts on island ecosystems. The New Caledonia archipelago is considered a biodiversity hotspot due to its diverse native flora. Javan rusa deer (Rusa timorensis) were introduced to New Caledonia in 1870 and the population consists of several hundred thousand individuals today. They directly threaten rare endemic species and affect the composition and structure of the vegetation. While a rusa deer management plan has identified ten priority areas for deer control operations, removing deer could be offset by the dispersal of animals back into the control areas. Here, we genotyped 628 rusa deer using 16 microsatellite markers to analyse the genetic structure of the animals in New Caledonia. We aimed to assess fine-scale genetic structure, to identify natural barriers to deer movement and to assess functional connectivity by optimising individual-based landscape resistance models. Our results suggested that rusa deer formed a single genetic population on the main New Caledonian island. The isolation-by-distance pattern suggested that female dispersal was limited, whereas males had larger dispersal distances. We assessed functional connectivity using different genetic distance metrics and all models performed poorly (mR2 ≤ 0.0043). Landscape features thus hardly affected deer movement. The characteristics of our results suggested that they were not an artefact of the colonisation history of the species. Achieving an effective reduction of deer population sizes in specific management areas will be difficult because of the deer’s high dispersal capabilities and impossible without very substantial financial investment.

Foreword

The Xth International Deer Biology Congress was held in Croatia in September, 2022. Topics covered included reviews of the present knowledge of the conservation, management, genetics, nutrition and health of deer and the use of antler products in the treatment of disease.

Comparative Analysis of Microsatellite and SNP Markers for Genetic Management of Red Deer.

The analysis of population genetic structure and individual multilocus heterozygosity are crucial for wildlife management and conservation. Microsatellite markers have traditionally been used to assess these genetic parameters. However, single-nucleotide polymorphisms (SNPs) are becoming increasingly popular. Our goal here was to determine to what extent SNPs can provide better insights than microsatellites into the overall genetic status and population genetic processes in the species. To this end, we genotyped 210 red deer (Cervus elaphus) in the Spanish wild population with both 11 microsatellites and 31,712 SNPs. We compared parameters related to population genetic structure and individual multilocus heterozygosity obtained with both types of markers. Our results showed correlations between parameters measured using both microsatellites and SNPs, particularly those related to the level of genetic diversity and genetic differentiation. However, we found notably lower precision of microsatellites in measuring the distribution of genetic diversity among individuals. We conclude that microsatellites can be used to monitor the overall genetic status and detect broad patterns in red deer populations. Nevertheless, the greater precision of SNPs in inferring genetic structure and multilocus heterozygosity leads us to encourage scientists and wildlife managers to prioritize their use whenever possible.

Socio-Political and Ecological Dimensions of Municipal Wildlife Management

In urban and suburban areas, the complex socio-environmental landscapes and diverging interests of stakeholders make wildlife management difficult. We analyze how municipalities in Massachusetts make decisions about the management of white-tailed deer (Odocoileus virginianus). Combining statistical analyses of a survey of municipal officials, qualitative analysis of management documents, and semi-structured interviews, we investigate (i) the socio-environmental conditions linked to municipal concerns about deer, (ii) the concerns that prompt municipalities to explore deer management actions, and (iii) why some municipalities take management action while others do not. We find that landscape features, Lyme disease incidence, and an array of concerns about deer prompt municipal governments to explore options for deer management. We show that management champions and small-scale politics are crucial in translating concern to management action. Our study illustrates the complexity of wildlife decision-making in sub/urban environments where the movement of wild animals intersects with patterns of development and politics.

Habitat utilization distribution of sika deer (Cervus nippon)

Habitat-specific and movement-related behavioral studies are essential for the development of sustainable biodiversity management practices. Although the number of studies on sika deer is increasing, habitat utilization distribution (UD)-related studies remain limited. In this study, we investigated the habitat UD behavior of sika deer (Cervus nippon) using a literature survey and an experimental study on Suncheon Bonghwasan Mountain, South Korea. We reviewed home range-related literature on sika deer published between 1982 and 2019 in order to assess their estimation methods, study region, and research background. We observed that the number of studies on sika deer has increased. The minimum convex polygon (MCP) has been utilized the most to estimate habitat UD, followed by the kernel density (KD), the Brownian bridge model, and a combination of these methods. The average home ranges (95 % utilization distribution) of sika deer from the literature survey were 236.99 ha and 1183.96 ha using the minimum convex polygon and kernel density approaches, respectively. The five female deer in our experimental study on Suncheon Bonghwasan Mountain had a mean home range of 66.831 ± 15.241 ha using the MCP approach and 78.324 ± 20.82 ha using the KD approach. The UD behavior of sika deer explored in this research is expected to benefit future scholars and policymakers when formulating deer management and wildlife conservation strategies.