Deer Populations Research Articles

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.

Mule deer mortality in the northern Great Plains in a landscape altered by oil and natural gas extraction

AbstractA worldwide increasing demand for renewable and non‐renewable energy resources has been ongoing since the mid‐1970s and is projected to increase for the next 2 decades. The effects of oil and natural gas development on wildlife mortality risk may play an important role in mule deer (Odocoileus hemionus) population dynamics. We evaluated the potential effects of oil and natural gas development on mortality risk of mule deer in western North Dakota and eastern Montana, USA. We assessed adult and juvenile female mule deer mortality risk with Poisson point process models using 265 deer fitted with global positioning system (GPS) radio‐collars that were deployed from 2013–2016. Mortality covariates included proportion of area disturbed by oil and natural gas development, distance to oil and natural gas development, distance to roads, temperature, snow depth, normalized difference vegetation index (NDVI), and age of deer. During the study there was no effect of oil and natural gas development or roads on mule deer mortality, though <1% of all deer locations were within 500 m of active drilling rigs. Mule deer mortality was greatest in winter and spring, and positively related to temperature during these seasons. Estimated annual adult survival probability was 0.79 (95% CI = 0.71–0.85). Given the strong influence of season and temperature variables on mortality risk, weather had the strongest influence on mule deer mortality during this study. Although we did not detect an effect of energy development on mule deer mortality, effects on space use resulting from development could influence deer dynamics in the region through displacement and could occur over longer time scales than we evaluated. This study can be used in pre‐development planning in a risk assessment framework to minimize effects of development on mule deer.

Intensive professional vehicle-based shooting provides local control of invasive rusa deer in a peri-urban landscape

Non-native deer are becoming increasingly common in peri-urban landscapes, where they pose a risk to the health and wellbeing of people. Professional vehicle-based shooting is commonly used to control deer populations in these complex landscapes, but the effectiveness and cost of this method have seldom been evaluated. We analyzed the effectiveness and cost of using professional vehicle-based shooting to reduce the abundance and impacts of non-native rusa deer (Cervus timorensis) in a peri-urban landscape in Wollongong, eastern Australia, during 2011–2021. We incorporated the results from an independent monitoring program into a Bayesian joint-likelihood framework to model spatio-temporal changes in rusa deer abundance. Finally, we used our findings to assess the effect of the management program on the number of complaints from the residents. After eleven years and the removal of 4701 rusa deer from Wollongong LGA (712 km2), deer abundance did not change in 74.7% of the area, decreased in 19.4% of the area (mostly in and around the sites where the professional shooting occurred), and increased in 5.9% of the area. Shooting was most cost-effective during winter when the longer hours of darkness meant that shooters could visit more sites. In contrast to deer abundance, the probability of residents complaining about deer increased in space and time. Our study shows that professional vehicle-based shooting can locally reduce the abundance of invasive deer in a peri-urban landscape, providing that sufficient control effort is expended. We suggest that shooting effort is currently too thinly spread across this peri-urban landscape, and that concentrating shooting effort on the areas of greatest deer abundance and resident complaints might be a more cost-effective strategy for managing invasive deer in peri-urban landscapes.

Urbanization and primary productivity mediate the predator–prey relationship between deer and coyotes

AbstractPredator–prey interactions are important for regulating populations and structuring communities but are affected by many dynamic, complex factors across large scales, making them difficult to study. Integrated population models (IPMs) offer a potential solution to understanding predator–prey relationships by providing a framework for leveraging many different datasets and testing hypotheses about interactive factors. Here, we evaluate the coyote–deer (Canis latrans–Odocoileus virginianus) predator–prey relationship across the state of North Carolina (NC). Because both species have similar habitat requirements and may respond to human disturbance, we considered net primary productivity (NPP) and urbanization as key mediating factors. We estimated deer survival and fecundity by integrating camera trap, harvest, and biological and hunter observation datasets into a two‐stage, two‐sex Lefkovich population projection matrix. We allowed survival and fecundity to vary as functions of urbanization, NPP, and coyote density, and projected abundance forward to test eight hypothetical scenarios. We estimated initial average deer and coyote densities to be 11.83 (95% CI: 5.64, 20.80) and 0.46 (95% CI: 0.02, 1.45) individuals/km2, respectively. We found a negative, though highly uncertain, relationship between the current levels of coyote density and deer fecundity in most areas that became more negative under hypothetical conditions of lower NPP or higher urbanization, leading to lower projected deer abundances. Though not conclusive, our results indicate the possibility that coyotes could have stronger effects on deer populations in NC if their densities rise, but primarily in less productive and/or more suburban habitats. Our case study provides an example of how IPMs can be used to better understand the complex relationships between predator and prey under changing environmental conditions.

Island demographics and trait associations in white-tailed deer.

When a population is isolated and composed of few individuals, genetic drift is the paramount evolutionary force and results in the loss of genetic diversity. Inbreeding might also occur, resulting in genomic regions that are identical by descent, manifesting as runs of homozygosity (ROHs) and the expression of recessive traits. Likewise, the genes underlying traits of interest can be revealed by comparing fixed SNPs and divergent haplotypes between affected and unaffected individuals. Populations of white-tailed deer (Odocoileus virginianus) on islands of Saint Pierre and Miquelon (SPM, France) have high incidences of leucism and malocclusions, both considered genetic defects; on the Florida Keys islands (USA) deer exhibit smaller body sizes, a polygenic trait. Here we aimed to reconstruct island demography and identify the genes associated with these traits in a pseudo case-control design. The two island populations showed reduced levels of genomic diversity and a build-up of deleterious mutations compared to mainland deer; there was also significant genome-wide divergence in Key deer. Key deer showed higher inbreeding levels, but not longer ROHs, consistent with long-term isolation. We identified multiple trait-related genes in ROHs including LAMTOR2 which has links to pigmentation changes, and NPVF which is linked to craniofacial abnormalities. Our mixed approach of linking ROHs, fixed SNPs and haplotypes matched a high number (~50) of a-priori body size candidate genes in Key deer. This suite of biomarkers and candidate genes should prove useful for population monitoring, noting all three phenotypes show patterns consistent with a complex trait and non-Mendelian inheritance.

Prevalence of nasopharyngeal myiasis in roe deer (Capreolus capreolus) from an area with high sympatry between wild and domestic ungulates in Central Spain

Infestation by the sheep bot fly Oestrus ovis was firstly reported in a single roe deer from Central Spain in 2022. For assessing the current situation of nasal myiases in this ungulate in this area, the nasopharyngeal cavities of 184 roe deer hunted in Central Spain between January-June 2023 were examined. All larvae were recovered and morphologically identified; in addition, species identification was molecularly confirmed in a subset of specimens. Forty-four roe deer (23.9%; CI 95 17.95–30.74) were positive for different Oestrinae larval stages. Twenty-six animals (14.1%; CI 95 9.44–20.02%) were infested by the roe deer nasal bot fly (Cephenemyia stimulator) with a mean intensity of 35.2 (SD 49.71) larvae/infested animal, and eighteen (9.8%; CI 95 5.90-15.02%) roe deer harboured the sheep bot fly (O. ovis), with a mean intensity of 2.0 (SD 1.33) larvae/infested animal. No mixed infestations by both Oestrinae were found in a single animal. All larval instars (L1, L2 and L3) of both species were identified. Most C. stimulator specimens were located at the nasal turbinates, and a small percentage (3.2%) at the pharynx; all O. ovis larvae were found at the nasal turbinates. Since O. ovis is highly prevalent in sheep and goat flocks from Central Spain, the high sympatry between roe deer and small ruminant populations in the studied area may have increased the risk of cross-infection. Moreover, the finding of mature L3 of O. ovis suggests that this species can complete its life cycle in roe deer. Therefore, monitoring bot flies in sheep and goat flocks as well as in sympatric wild ruminants is strongly recommended for achieving an optimum control of nasal myiases.

Detection of Bartonella spp. in farmed deer (Artiodactyla: Cervidae) using multiplex assays in the Qinghai-Tibet Plateau, China.

This is the first report about Bartonella infections in the deer population from China. We found that there were two species of Bartonella and an unidentified species of Bartonella among the unculturing strains carried by these deer populations. We first used Nanopore sequencing to detect Bartonella from deer blood samples and indicated that Nanopore sequencing is beneficial to detect pathogens due to its advantage of real-time and high sensitivity.

Assessing hurricane impact on vegetation and endangered deer habitat using airborne lidar and multispectral images

In the lower Florida Keys, the endangered Florida Key deer and numerous other wildlife species inhabit a vulnerable island environment susceptible to storm surges and rising seawater due to low elevation and flat terrain. Timely and reliable assessment of vegetation damage from natural disasters, such as Hurricane Irma, is crucial for effective habitat management. The study’s overall objective is to examine Hurricane Irma’s impact on vegetation on No Name Key, Florida, using remote sensing. The study relates the area change in vegetation obtained from remote sensing analysis to Florida Key deer population changes following the storm. The methodology involved performing a thematic change detection analysis using the following data sources: (1) aerial multispectral images (for pre- and post-Hurricane), (2) airborne lidar data (for pre- and post-Hurricane), (3) an existing vegetation map, and (4) soil data. A Support Vector Machine (SVM) image classification algorithm was applied to pre- and post-storm input image stacks to create pre- and post-Hurricane Irma vegetation maps. We were then able to obtain the area change information (for various vegetation categories) by performing the change detection analysis of the 2 SVM-classified images. The differences in areas following the storm were calculated for 7 affected vegetation types. Using the area change information following Hurricane Irma, we estimated the number of deer supported by the storm-affected vegetation. These estimated deer numbers, based on the area differences in post-Hurricane Irma vegetation types, were compared to observed deer numbers collected during the post-Hurricane Irma Texas A&M Natural Resources Institute (NRI) deer field survey. The results showed the following: mangroves had the largest negative area changes (area loss), followed by pinelands, hardwoods/hammocks, developed areas, and buttonwoods. Freshwater marshes had the largest positive area changes (area gain). The deer's preferred vegetation areas had decreased post-Hurricane Irma, resulting in a reduced deer population compared to pre-storm numbers. The predicted number of the Key deer post-Hurricane Irma fell within a 95% confidence interval of the observed deer population from the post-storm field survey. The study findings and techniques could be applied to study climate change impact, especially sea level rise. This methodology can be valuable in assessing the impact of storms on other wildlife species in similar environments. The applications and methodology are especially relevant considering the increasing frequency and intensity of storm surges and the accelerating rate of sea level rise.

Persistence of viral RNA in North American elk experimentally infected with an ancestral strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

White-tailed deer (Odocoileus virginianus) have emerged as a reservoir host for SARS-CoV-2 given their susceptibility to infection and demonstrated high rates of seroprevalence and infection across the United States. As SARS-CoV-2 circulates within free-ranging white-tailed deer populations, there is the risk of transmission to other wildlife species and even back to the human population. The goal of this study was to determine the susceptibility, shedding, and immune response of North American elk (Cervus elaphus canadensis) to experimental infection with SARS-CoV-2, to determine if another wide-ranging cervid species could potentially serve as a reservoir host for the virus. Here we demonstrate that while North American elk do not develop clinical signs of disease, they do develop a neutralizing antibody response to infection, suggesting the virus is capable of replicating in this mammalian host. Additionally, we demonstrate SARS-CoV-2 RNA presence in the medial retropharyngeal lymph nodes of infected elk three weeks after experimental infection. Consistent with previous observations in humans, these data may highlight a mechanism of viral persistence for SARS-CoV-2 in elk.

Modeling the impact of sea level rise on endangered deer habitat

Numerous unique flora and fauna inhabit the Lower Florida Keys, including the endangered Florida Key deer, found nowhere else. In this vulnerable habitat of flat islands with low elevation, accelerated sea level rise poses a threat. Predicting the impact of sea level rise on vegetation and wildlife is crucial. This study used 5 Intergovernmental Panel on Climate Change (IPCC) sea level rise scenarios to assess their effects on No Name Key, Florida. The goal was to estimate changes in the Florida Key deer population relative to sea level rise using a lidar-derived elevation data and a vegetation map. The method used 2 cases to model the sea level rise impact. In Case 1, total non-submerged area at current sea level was determined. Using 5 IPCC scenarios, a new total non-submerged land area was estimated, and deer numbers were predicted for each scenario. In Case 2, upward migration of coastal vegetation combined with the coastal squeeze process was modeled. A distinct elevation range for each vegetation type at the current sea level was determined. Vegetation ranges were redistributed based on respective elevation ranges in the sea level rise scenarios. Areas for each vegetation type were recalculated, and Key deer numbers were estimated for each sea level rise scenario. Results under the worst emission scenario showed the following: (1) for case 1, the land area was reduced to 30 % of the current land area, corresponding to having about 27 deer, and (2) for case 2, the land area was reduced to 70 % of the current land area, having about 54 deer on No Name Key. The results indicated reduced non-submerged land area and less upland vegetation, particularly hardwoods/hammocks, by the year 2100. As less land area is available, a decline in Key deer population is expected as sea levels rise. Since Key deer favor upland vegetation, habitat affected by sea level rise will likely support a smaller deer population. The findings emphasize the need for precise, timely predictions of sea level rise impacts and long-term conservation strategies. Specifically designed measures are required to protect and maintain endangered wildlife, such as the Florida Key deer, residing on these vulnerable islands.

Helminth Prevalence in European Deer with a Focus on Abomasal Nematodes and the Influence of Livestock Pasture Contact: A Meta-Analysis.

Deer are susceptible to infection with parasitic helminths, including species which are of increasing economic concern to the livestock industry due to anthelmintic drug resistance. This paper systematically collates helminth prevalence data from deer across Europe and explores patterns in relation to host and parasite species, as well as landscape factors. A livestock pasture contact index (LPCI) is developed to predict epidemiological overlap between deer and livestock, and hence to examine deer helminth fauna in the context of their surrounding environment. Fifty-eight studies comprising fallow (Dama dama), red (Cervus elaphus), roe (Capreolus capreolus) and sika (Cervus nippon) deer were identified. Deer populations in "likely" contact with livestock pasture had a higher mean prevalence of the abomasal nematodes Haemonchus contortus, Ostertagia ostertagi, Teladorsagia circumcincta and Trichostrongylus axei (p = 0.01), which are common in livestock and not primarily associated with deer. Roe deer populations had a higher prevalence of T. circumcincta (p = 0.02) and T. axei (p = 0.01) than fallow deer and a higher prevalence of H. contortus than both red (p = 0.01) and fallow deer (p = 0.02). Liver fluke and lungworm species were present sporadically at low prevalence, while the abomasal nematode Ashworthius sidemi occurred locally at high prevalence. Insights from this research suggest that deer helminth fauna is reflective of their surrounding environment, including the livestock species which inhabit areas of shared grazing. This is explored from an epidemiological perspective, and the prospect of helminth transmission between wild and domestic hosts is discussed, including drug-resistant strains, alongside the role of helminths as indicators relevant to the transmission of other pathogens at the wildlife-livestock interface.

Social and Seasonal Organisation of Red Deer Hunting from the Neolithic to the Late Iron Age (c. 2000 BC to AD 1000)

This is the first paper to examine social and seasonal organization of red deer hunting using stone-set hunting blinds in Norway. The paper examines seven hunting blinds discovered in Gjesdal, western Norway. Four of the hunting blinds are unique; it was possible to date them directly with radiocarbon dating. The sites exhibit multiple construction phases, with a usage period ranging from the Neolithic to the Mid Iron Age, and we would suggest likely extending into the Late Iron Age and Middle Ages. The datings and multiple phases make it possible to discuss temporal change in the construction of the hunting blinds, which is unprecedented in a Fennoscandian context. Hunting appears to align with social trends, becoming more prominent during periods of settlement decline and increased use of outfield resources for surplus production. While hunting in the lowlands of western Norway, particularly between 0 and 900 metres above sea level, appears to have been smaller in scale compared to mass-scale hunting in Norway’s high-altitude zones and eastern regions, the high population of red deer until about 500 years ago indicates profitable hunting opportunities during specific seasons. The cluster of hunting blinds suggests organized cooperation among neighbours and families, with surplus products potentially sold and exported to local and regional markets.

Dissecting the Effects of Cephenemyia stimulator on the Olfactory Turbinates and Nasopharynx of Roe Deers (Capreolus capreolus).

Nasopharyngeal myiasis in European roe deer (Capreolus capreolus) is a pathological condition caused by the larval stages of Cephenemyia stimulator, a fly from the Oestridae family. These larvae reside in the host's upper respiratory tract for months, inducing significant tissue damage and clinical symptoms. The lifecycle of Cephenemyia stimulator is complex, involving three larval stages before maturation into adult flies, with each stage contributing to the progressive pathology observed in the host. Despite their prevalence, the histopathological effects of these larvae in the nasal and nasopharyngeal cavities have been understudied. Our study fills this knowledge gap by providing a detailed histopathological analysis of the affected tissues, using various staining techniques to reveal the extent and nature of the damage caused by these parasitic larvae. This histopathological examination reveals significant alterations within the nasopharyngeal mucosa and nasal cavity, including erythematous changes, mucosal metaplasia, fibrosis, and tissue necrosis. Parasitic cysts and eosinophilic infiltration further characterize the impact of the infestation, compromising not only the mucosal integrity but also potentially the olfactory function of the affected animals. This research is crucial for understanding the impact of myiasis on both the health and olfactory capabilities of roe deer populations and could have significant implications for wildlife management and conservation.

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.

Female Deer Movements Relative to Firearms Hunting in Northern Georgia, USA.

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.

Planning for Deer-Hunting Management at the Local and Regional Scales: Reconciling Economic, Social and Ecological Functions

Game species with home ranges exceeding the area of the management units may entail conflicts over hunting rights and cause damage to crops and forest stands in surrounding areas. This is currently the case in the Mendro Mountain Range (Portugal), inhabited by free-ranging red (Cervus elaphus) and fallow deer (Dama dama) populations. This study’s primary goal was to uncover the processes underlying these tensions and identify solutions to overcome them, thus reconciling the economic, social, and ecological functions of hunting. We analyzed data from three different sources of information regarding the surveyed management units: biophysical and anthropical spatial data collected using a GIS; typology, whether fenced, area and game bag results, data provided by a public institute; crop and forest damage locations reported by game managers. Approximately half of the surveyed open management units reported damage. We found no relationship between damage and game bag results, regardless of the typology and habitat quality index. To address this disconnection between the negative and positive values associated with deer locally, we proposed habitat management solutions. It is of chief importance to keep valuable crops apart from deer’s refuge cover, such as bushy areas, to minimize damage in management units where deer hunting is a subsidiary activity. Conversely, in management units where deer hunting is of significant economic importance, the food and refuge cover should be closely interspersed to increase the management unit’s carrying capacity. To improve the efficacy of measures such as this at a regional scale, as in the Mendro Mountain Range, we recommend implementing a so-called Global Management Plan. In Portuguese law, this governance instrument applies to the entire biologic unit where the deer populations occur, thus implying arrangements between the involved stakeholders and multiple other concerned institutions.

Same landscape, different connectivity: contrasting patterns of gene flow in two sympatric ungulates in a mountain area

Comparative landscape genetics studies provide insights on the impact of landscape elements on gene flow patterns of different species inhabiting the same geographic area. We investigated the population genetic structure of two sympatric ungulates, roe deer Capreolus capreolus and Northern chamois Rupicapra rupicapra, in a mountain area of the central Italian Alps (Trentino, northern Italy). A total of 122 chamois and 72 roe deer samples were genotyped by two species-specific panels of 11 polymorphic microsatellite loci and analyzed by aspatial and spatially explicit analyses. While the roe deer population resulted unstructured, a clear population structure was detected in chamois, with two main groups, one inhabiting the eastern and the other spread in the western part of the study area. Landscape genetics analysis confirmed these scenarios and revealed a different effect of landscape on gene flow. An IBD (Isolation-By-Distance) model best explained genetic variation in roe deer, while IBR (Isolation-By-Resistance) was found as the process underlying genetic variation patterns in chamois, suggesting arable lands, coniferous forests, watercourses, and main roads as potential barriers. Species distribution and landscape use might explain these results: roe deer mostly occupy valley floors relatively connected to each other, and their spatial behavior may promote gene flow across areas. On the other hand, chamois prefer higher elevations and their movements may be hindered by valleys, rivers, and road networks. This study highlights the different impacts of natural and anthropic landscape elements on gene flow in two sympatric species, resulting from their different ecological requirements.

Faecal Standing Crop with real time correction using scat detection dogs to estimate population density

Abstract Population density is fundamental information for assessing the conservation status of species and support management and conservation actions for in situ populations, but is unknown for many forest species due to their difficulty in detection. The Faecal Standing Crop (FSC) method using detection dogs is an alternative for cryptic or elusive species. An intrinsic difficulty of FSC is the ability to find faecal samples in the field and to estimate the probability of which faeces detection is influenced by degradation due to climatic conditions. Our goal was to propose a concurrent FSC parameter estimation using a scat detection dog under different climatic conditions and apply those parameters in a wild deer population. Ten faecal samples of grey brocket deer (Subulo gouazoubira) were placed weekly in a transect (24 × 1440 m) in both dry and wet seasons (12 weeks each). A scat detection dog was then employed to find experimental faecal samples to determine the FSC parameters that were subsequently used with naturally occurring faecal samples (also dog‐detected) to estimate population density. The oldest dog found samples were 21 (Dry) and seven (Wet) days after placement, resulting in dog efficiency of 22.5% (Dry) and 30% (Wet). Adjusting the model to account for efficiency and scat durability, we estimated similar, seasonal, densities of 4.51 individuals km−2 (SD = 2.21, Dry) and 5.37 individuals km−2 (SD = 3.71, Wet). Synthesis and applications: Our results demonstrate that our concurrent methodology corrected the effects of weather and habitat on FSC parameters thereby allowing for accurate population density estimation. Additionally, this method can provide reasonably precise density estimates with a logistically feasible sample size, as demonstrated by simulation. Following our recommendations, this method allows a reliable estimate of population density because it incorporates any influence of study area, dog ability and climate in faecal sample detection, providing fundamental information for the conservation of many cryptic and elusive species.

Predicting the odds of chronic wasting disease with Habitat Risk software

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy that was first detected in captive cervids in Colorado, United States (US) in 1967, but has since spread into free-ranging white-tailed deer (Odocoileus virginianus) across the US and Canada as well as to Scandinavia and South Korea. In some areas, the disease is considered endemic in wild deer populations, and governmental wildlife agencies have employed epidemiological models to understand long-term environmental risk. However, continued rapid spread of CWD into new regions of the continent has underscored the need for extension of these models into broader tools applicable for wide use by wildlife agencies. Additionally, efforts to semi-automate models will facilitate access of technical scientific methods to broader users. We introduce software (Habitat Risk) designed to link a previously published epidemiological model with spatially referenced environmental and disease testing data to enable agency personnel to make up-to-date, localized, data-driven predictions regarding the odds of CWD detection in surrounding areas after an outbreak is discovered. Habitat Risk requires pre-processing publicly available environmental datasets and standardization of disease testing (surveillance) data, after which an autonomous computational workflow terminates in a user interface that displays an interactive map of disease risk. We demonstrated the use of the Habitat Risk software with surveillance data of white-tailed deer from Tennessee, USA.

Zoogeochemistry of a protected area: Driven by anthropogenic impacts and animal behavior

AbstractAnthropogenic eutrophication of ecosystems is an important driver of biodiversity loss. Even protected areas (PAs) may be impacted by anthropogenic nutrients, for example, from atmospheric deposition or the provision of supplementary feeding. However, the resultant nutrient patterns, and the role of local wildlife in shaping them, remain poorly understood. We investigated anthropogenic influences on the role that red deer (Cervus elaphus) play in the nutrient balance of a PA in Denmark. We used habitat selection modeling and theoretical scenarios where we varied the proportion of energy the deer obtained from supplementary versus natural forage and compared it with the nutrients removed due to hunting. We show that the movement and distribution of the red deer population within the PA are very heterogeneous and likely influenced by the need for shelter. Moreover, depending on their reliance on supplementary feeding, deer can potentially import large amounts of nutrients to the PA, and concentrate them in localized hotspots. However, we also explore the potential for nutrient loss due to hunting activities. Such indirect anthropogenic impacts on nutrient landscapes may counteract restoration and conservation efforts. We therefore recommend incorporating anthropogenic influences on zoogeochemistry and the animal‐mediated connectivity between PAs and anthropogenically dominated landscapes into future management plans.