Red Deer Population Research Articles

Antler size in red deer: declining selection and increasing genetic variance with age, but little senescence

Abstract While senescence is a common occurrence in wild populations, not all traits decline with age simultaneously and some do not show any senescence. A lack of senescence in secondary sexual traits is thought to be due to their importance for reproductive success. However, if reproductive success senesces, why would secondary sexual traits apparently not senesce? Here, we explored this question in a wild population of red deer (Cervus elaphus) using antler form (number of points), a secondary sexual trait which shows little senescence, despite the occurrence of reproductive senescence. In line with expectations for traits that senesce, genetic variance in antler form increased with age and selection weakened with age. Therefore, there was no indication that a stronger selection on individuals that survived to older ages was countering the dilution of selection due to fewer individuals being alive. Furthermore, the effect of selective disappearance masking a slight decline in antler form in the oldest years was small. Interestingly, although genetic variance and positive selection of antler form were found, there was no evidence of a response to selection, supporting a genetic decoupling of antler senescence and reproductive senescence. Finally, a positive genetic covariance in antler form among age classes provides a possible explanation for the lack of senescence. These findings suggest that the antler form is under a genetic constraint that prevents it from senescing, providing an interesting evolutionary explanation for negligible senescence in a secondary sexual trait, and consequently, the existence of asynchrony in senescence among traits within populations.

Analysis of the genetic diversity of Tahe red deer and population structure of Cervus elaphu/hanglu/canadensis

The Tahe red deer is currently the largest breeding population of antlered Cervus elaphus in China. It has unique characteristics such as drought and roughage tolerance, high antler yield and early sexual maturity. It is a high-quality provenance for cultivating high-yield Cervus elaphus breeds and is also the subject of study on the origin, evolution, and classification of Cervus elaphus. The breeding quantity of Tahe red deer has decreased significantly in recent years due to the influence of feeding conditions and consumer market. This has resulted in a serious threat to its genetic resources. To provide a scientific theoretical basis for the protection of the Tahe red deer population, we performed PCR amplification and direct sequencing of the AMELY2, DBY and SRY genes of the Y chromosome, and the ND1, COX1, ATP6, ND5, Cyt b and D-loop regions of the mtDNA, and analysed their genetic diversity and population genetic structure. The results showed high haplotype diversity and low nucleotide diversity in both the Y chromosome and mtDNA genes. The phylogenetic tree and haplotype network diagram, constructed using white-lipped deer as the outgroup, indicate that Tahe red deer has two distinct ancestral types. The phylogenetic tree, based on the Cyt b gene and D-loop region, reveals that the Cervus elaphus/hanglu/canadensis is divided into three clades: western, central, and eastern. Tahe red deer, C.h.bactrianus, and C.h.hanglu are clustered in the central clade. The study results indicate that Tahe red deer has low genetic diversity and two distinct ancestor types. It is speculated that the central clade is either the earliest differentiation from the ancestor species or the closest to it.

Red deer grazing pressure on agricultural grass meadows from broad to local scale

Grazing by wildlife on agricultural land is widespread across geographical regions, and can cause human–wildlife conflicts due to reduced crop yield when the grazing pressure is high. Growing red deer Cervus elaphus populations in Europe call for an increased understanding of their grazing patterns to mitigate damages. We quantified how red deer grazing pressure (grazing presence and grazing level) on agricultural grass meadows (n = 60) in Norway varied across multiple spatial scales. We used a nested, hierarchical study design transcending from a broad scale (meadows across the landscape) to intermediate (between nearby meadows) and local (within‐meadow) scales, allowing us to identify at which scale the variation in grazing pressure was strongest. We estimated how grazing was determined by broad‐scale factors influencing forage availability and quality through population density, distance to coastline, and differences between the first versus second harvest, by intermediate‐scale factors in terms of meadow management causing differences in botanical composition and quality, and by local‐scale factors in terms of perceived predation risk and disturbance. At a broad scale, higher population densities were associated with higher grazing pressure, and more grazing occurred before the first compared to the second harvest. Intermediate‐scale factors explained the most variation of grazing pressure from red deer, with higher grazing pressure on newly renewed meadows compared to other nearby meadows. On a local scale, more grazing occurred closer to the forest edge, providing cover, and further away from infrastructure, with increased risk and disturbance. Overall, our study highlights how drivers of grazing pressure on agricultural land vary across spatial scales. Population reductions on a broader scale may have some effect in reducing the grazing pressure, but renewed meadows will nevertheless attract red deer, causing higher grazing pressure compared to neighbouring meadows. This insight is crucial for determining effective mitigation strategies facing rising red deer populations across Europe.

Novel insights into red deer (Cervus elaphus) habitat use and suitability in human-dominated versus near-natural landscapes

Abstract Red deer populations, once extirpated in large parts of Europe, have recovered over the last century in many regions. In Switzerland, primarily inhabiting mountain forests, they have recently started to expand into human-dominated lowland landscapes. To study their habitat selection, we analyzed day- and nighttime positions of 15 GPS-collared red deer. Our results show that during daytime, all animals generally preferred forests; open land was mainly used at night. In summer and fall, some lowland individuals deviated from this pattern and used agricultural crops as daytime retreats. Human settlements were often avoided in the lowlands. Day-site selection in the lowlands occurred irrespective of the distance to trails and the probability of being accessed by humans, in contrast to the pattern observed in the mountains. At night, red deer preferred forest edges and open land. In the lowlands, human settlements were avoided. Trails and transport infrastructures had a marginal influence at night. Our study confirmed a high behavioral plasticity of red deer. The use of daytime retreats close to trails and in high-standing crops represent major extensions of their behavior. Our habitat models indicate that there is ample suitable habitat in the lowlands, which is of major relevance for their management.

The gut microbial differences between pre-released and wild red deer: Firmicutes abundance may affect wild adaptation after release.

Insufficient density of red deer has affected the stability of forest ecosystems and the recovery of large carnivores (represented by Amur tiger). Conservation translocations from captivity to the wild has become an important way to restore the red deer populations. However, the difference in gut microbes between pre-release and wild red deer may affect the feeding adaptability of red deer after release. In this study, we clarified the differences in gut microbes between pre-released and wild red deer and screened the key gut microbes of the red deer involved in feeding by using metagenomic sequencing and feeding analysis. The results showed that the microbial difference between pre-released and wild red deer was mainly related to Firmicutes represented by Eubacteriales and Clostridia, and Firmicutes abundance in pre-released red deer (68.23%) was significantly lower than that of wild red deer (74.91%, p < 0.05). The expression of microbial metabolic pathways in pre-released red deer were significantly lower than those in wild red deer (p < 0.05), including carbohydrate metabolism, amino acid metabolism, glycan biosynthesis and metabolism, etc. The combinations of Firmicutes were significantly positively correlated with the intake of plant fiber and carbohydrate (p < 0.05), and were key microbes to help red deer deal with wild plant resources. Additionally, the combinations of Firmicutes represented by Eubacteriales and Clostridia lacking in pre-released red deer contributed the most to expression of microbial metabolic pathways (importance > 1), showing a significant positive correlation (p < 0.05). This study indicates that high abundance of Firmicutes is an important guarantee for red deer to adapt to the wild feeding environment, which provides critical implications for the recovery of red deer populations and the protection of endangered ungulates.

Occurrence, ecology and management of Fascioloides magna in Bavaria, southern Germany

In 2015, red deer infected with American liver fluke were discovered in the Veldenstein Forest area for the first time. This was the first detection of the fluke in a wild deer population in Bavaria. The aim of the study was to determine the American liver fluke prevalence rates in red deer, roe deer and wild boar in the Veldenstein Forest, as well as factors influencing these rates. Since 2018, the livers of 83% of the red deer culled in the study area have been examined, as well as those of the occasional roe deer and wild boar. The livers are classified by adspection and dissection into four levels of infection. The age of the animals was estimated based on dentition and tooth cementum annuli in the first molar (M1). The livers of 520 red deer, 226 roe deer and 75 wild boar were dissected. All wild boar livers tested negative. 3% of roe deer and 36% of red deer livers were positive. The red deer population was reduced to lower the prevalence, beginning in 2018. In the following years, it fell significantly. Medium and high infection levels were initially detected in 61% of adult red deer. Since 2018, the median number of flukes per infected liver has decreased significantly from 17.51 flukes/liver to 10.0 flukes/liver. On driven hunts, significantly more diseased deer were found than during hunting from raised hides. Furthermore, there are close correlations between the age of the red deer, infections, and the distance from the Pegnitz floodplains. The American liver fluke leads to the extinction of roe deer locally and to a massive infection and decimation of the red deer. Without a drastic reduction in the number of infected deer populations, there is a risk of large‐scale infection of native deer species across Bavaria.

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.

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.

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.

Genetic architecture of inbreeding depression may explain its persistence in a population of wild red deer.

Inbreeding depression is of major concern in declining populations, but relatively little is known about its genetic architecture in wild populations, such as the degree to which it is composed of large or small effect loci and their distribution throughout the genome. Here, we combine fitness and genomic data from a wild population of red deer to investigate the genomic distribution of inbreeding effects. Based on the runs of homozygosity (ROH)-based inbreeding coefficient, FROH, we use chromosome-specific inbreeding coefficients (FROHChr) to explore whether the effect of inbreeding varies between chromosomes. Under the assumption that within an individual the probability of being identical-by-descent is equal across all chromosomes, we used a multi-membership model to estimate the deviation of FROHChr from the average inbreeding effect. This novel approach ensures effect sizes are not overestimated whilst maximising the power of our available dataset of >3000 individuals genotyped on >35,000 autosomal SNPs. We find that most chromosomes confer a minor reduction in fitness-related traits, which when these effects are summed, results in the observed inbreeding depression in birth weight, survival and lifetime breeding success. However, no chromosomes had a significant detrimental effect compared to the overall effect of inbreeding, indicating no major effect loci. We conclude that in this population, inbreeding depression is likely the result of multiple mildly or moderately deleterious mutations spread across all chromosomes, which are difficult to detect with statistical confidence. Such mutations will be inefficiently purged, which may explain the persistence of inbreeding depression in this population.

Between the lines: mitochondrial lineages in the heavily managed red deer population of Belarus

Between the lines: mitochondrial lineages in the heavily managed red deer population of Belarus

Faecal cortisol levels in a wild Iberian red deer population are best explained by prior weather conditions

AbstractThe responsiveness of the hypothalamic–pituitary‐adrenocortical axis to stressors is crucial for wild animals to survive and adapt to environmental changes without compromising individual welfare. We analysed the influence of prior weather conditions, seasonality, the influx of ecotourism, and nutrition on stress levels in a wild population of red deer in a Mediterranean hunting reserve in the Pre‐Pyrenees, Spain. We used faecal cortisol metabolites as a proxy for physiological and psychological stress, and faecal triiodothyronine metabolites as an indicator of nutritional stress. Faecal analyses were chosen because it is a non‐invasive technique that does not alter an individual's behaviour, and it is easy to conduct in a wild population, something which presents added challenges due to the lack of a controlled environment. Our results indicate that prior weather conditions, rather than just seasonality, best explained the variations in these hormones within seasons and among years. On the contrary, the results showed that high levels of the cortisol hormone did not necessarily correspond to low levels of the triiodothyronine hormone. This could be a sign of acute nutritional stress in this population. Finally, we did not find an effect of the ecotourism influx on cortisol levels, suggesting that this deer population tolerates the presence of tourists.

A case study for best suitable methods of monitoring demographic structure in cervid populations to predict increasing forest damages

The overall increase of ungulate populations in modern Europe has contributed to conflicts in national economies, particularly between game management and the forestry sector. This study assessed damage risks to young pine (Pinus sylvestris L.), spruce (Picea abies (L.) H. Karst.) and aspen (Populus tremula L.) stands at two spatial scales. One level assessed the interaction between sex-age structure of cervid populations, measured by pellet group density, and forest damages, measured as the percentage of heavily browsed trees in 2040 stand surveys distributed proportionally throughout the country. The second level compared pellet counts and trail-camera-based records of moose (Alces alces L.) and red deer (Cervus elaphus L.) presence in a pilot study area. We examined whether 1) there is a correlation between damage amount and ungulate population structure and 2) are the data from trail cameras suitable for wider use in monitoring ungulate population structure. The study confirmed significantly higher moose pellet group densities in pine than in spruce and aspen stands. Pine damages were greater in stands with higher moose pellet group density, especially with female moose prevailing over male moose density index. The red deer pellet group densities were significantly higher in heavily damaged pine and spruce stands, regardless of sex-age structure. In most cases, there were no statistically significant differences between the two survey methods of ungulate population structure by using pellet count transects and trail camera fixations. Both methods provide comparable data on sex-age structure in moose and red deer populations if seasonal and habitat-predicted biases are considered. However, trail cameras are more widely applicable and easier to use by hunters than pellet counts.

STUDY REGARDING THE EVOLUTION OF THE WILD ANIMALS POPULATIONS FROM SEACA HUNTING FUND (OLT COUNTY)

The prospects for game fauna, edible or non-edible, for game culture or just for bringing their populations under control, are only likely and different from species to species. The purpose of this paper is to follow the evolution of the populations of game fauna in the Seaca No. 4 Hunting Fund (Olt County) in the period 2011–2021, in order to deepen and improve the existing game management. The surface of the game reserve is 8,661 ha and overlaps with 3 protected areas. During the research period, 9 representative species of hunting interest were identified, important from an ecological, economic and aesthetic point of view: 7 mammal species (belonging to 3 orders, 5 families) and 2 bird species (Phasianidae). Of the species of game interest studied, only the European fallow deer (an artificially introduced species), roe deer and red fox showed an increase in the number of animals, their hunting quotas and, therefore, their harvests during the research period. We mention the reduction in the wild boar herds, in spite of the special care taken by the administrator to supplement their food requirements, and the appearance and multiplication of jackals in the area, the multiplication of red foxes and the reduction in the European hare and gray partridge numbers. Comparing the actual and optimum populations in 2021, it can be observed that the actual population of roe deer, red deer and pheasant is close to the optimum population level. Thus, during the research period, the herds of hunting fauna were relatively high and balanced, in accordance with the diversity of the habitats and the large number of facilities for hunting. The need is felt to protect the habitats and further develop the territory where game is taken care of and harvested in the context where the habitats are subject to alarming changes, which affect both the trophic capacity and the shelter needed by the game. The hunters from the studied hunting fund must maintain a sincere and constructive dialogue with the other actors in the field, in order to be able to take, jointly, the most appropriate measures for the conservation of wild fauna, without harming protected areas, agricultural production, forestry, etc.

Application of the tyraliera counting method to the large-scale inventory of red deer Cervus elaphus in the northern part of Western Pomerania, Poland

Game animal damage in the forests and fields of Central Europe, which dramatically increased at the turn of the 21st century, has undermined the reliability of the size of game population estimates. It is hypothesized that this problem can be attributed to errors in the assessment of animal density. This study conducted game inventories in a region characterized by a large ungulate population using a count method with drivers in line formation (direct counts in control plots). The size of the red deer population in the investigated area was estimated using generalized linear models assuming a negative binomial distribution based on the compound distribution (including the zero-inflated model). The mean red deer density in spring 2012 was 21.5 animals/km2 of forest. The number of red deer determined during this study is often higher that hunters indicated in annual game management plans. For the rational management of populations, it is therefore necessary to verify those estimates periodically, e.g. every five years. The statistical analysis of data from tyraliera method counts may show the actual population size during spring. Thus, it can be the basis for adequately planning hunting bags. Adjusting the population density to the carrying environmental capacity should make it possible to reduce the pressure of red deer on forests and agricultural land.

Numerical top‐down effects on red deer (Cervus elaphus) are mainly shaped by humans rather than large carnivores across Europe

Abstract Terrestrial ecosystems are shaped by interacting top‐down and bottom‐up processes, with the magnitude of top‐down control by large carnivores largely depending on environmental productivity. While carnivore‐induced numerical effects on ungulate prey populations have been demonstrated in large, relatively undisturbed ecosystems, whether large carnivores can play a similar role in more human‐dominated systems is a clear knowledge gap. As humans influence both predator and prey in a variety of ways, the ecological impacts of large carnivores can be largely modified. We quantified the interactive effects of human activities and large carnivore presence on red deer (Cervus elaphus) population density and how their impacts interacted and varied with environmental productivity. Data on red deer density were collected based on a literature survey encompassing 492 study sites across 28 European countries. Variation in density across study sites was analysed using a generalized additive model in which productivity, carnivore presence (grey wolf, European lynx, Brown bear), human activities (hunting, intensity of human land‐use activity), site protection status and climatic variables served as predictors. The results showed that a reduction in deer density only occurred when wolf, lynx and bear co‐occurred within the same site. In the absence of large carnivores, red deer density varied along a productivity gradient without a clear pattern. Although a linear relationship with productivity in the presence of all three large carnivore species was found, this was not statistically significant. Moreover, hunting by humans had a stronger effect than the presence of all large carnivores in reducing red deer density and red deer density increased with increasing intensity of human land use, with stronger large carnivore effects (all three carnivore species present) at sites with low human land‐use activities. Synthesis and applications. This study provides evidence for the dominant role played by humans (i.e. hunting, land‐use activities) relative to large carnivores in reducing red deer density across European human‐dominated landscapes. These findings suggest that when we would like large carnivores to exert numeric effects, we should focus on minimizing human impacts to allow the ecological impacts of large carnivores on ecosystem functioning.

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.

Estimating red deer population size using vantage point counts at baited sites

AbstractAccurate estimates of population size are central to the management and conservation of wild ungulates. Counting animals from vantage points of baited sites is a method that is traditionally used in Europe to obtain abundance estimates of wild ungulates, but its reliability in forested landscapes is contested. We assessed the accuracy of vantage point counts (VPCs) for estimating population size in red deer (Cervus elaphus) at De Hoge Veluwe National Park, a fenced, partially forested game reserve in the Netherlands. We compared estimates from duplicated VPCs for 1977–2010 with population sizes reconstructed from cohort analyses of age‐specific mortality records, including and excluding supplementation with vehicular direct counts (VDCs) and field knowledge on herd composition and herd size from game wardens. Estimates from VPCs supplemented with VDCs matched the reconstructed population size well for 2001–2010. In addition, estimates based on ≥1 VPC site/11 km2 provided representative estimates of the reconstructed population size in that period. Simultaneous VPCs at multiple baited sites can yield precise population estimates for red deer in forests.

The effect of COVID-19 confinement on the activity behaviour of red deer.

The COVID-19 pandemic has drastically affected people's social habits, especially those related to outdoor activities. We intended to understand the effects of the two national lockdowns in Portugal on the presence and activity of a wild population of red deer (Cervus elaphus) by analysing data from camera traps installed at Lousã mountain, in the central part of Portugal. The cameras were set between 2019 and 2021, and a total of 2434 individual contacts of red deer and 182 contacts of people were recorded. Results showed a higher human presence in the mountain area during the COVID-19 outbreak, especially during the first lockdown in 2020 (0.05±0.17 individuals/day), compared to the same period of the year before the pandemic (0.02±0.05 individuals/day), which resulted in an increase of people by 150%. The increase in human presence did not have a significant direct effect on the presence of red deer. Despite the low overlap of activity patterns between people and red deer, deer showed avoidance behaviour in the 24h after the detection of human presence on camera traps, as well as an increase in daily activity during the 2020 lockdown, showing red deer's awareness of human visitation. These results showed that people's increased search for cultural services in wild environments during COVID-19 lockdowns, such as hiking and biking, seemed to influence the population of red deer, albeit momentarily.

Estimating and managing broad risk of chronic wasting disease spillover among cervid species

AbstractThe management of infectious wildlife diseases often involves tackling pathogens that infect multiple host species. Chronic wasting disease (CWD) is a prion disease that can infect most cervid species. CWD was detected in reindeer (Rangifer tarandus) in Norway in 2016. Sympatric populations of red deer (Cervus elaphus) and moose (Alces alces) are at immediate risk. However, the estimation of spillover risk across species and implementation of multispecies management policies are rarely addressed for wildlife. Here, we estimated the broad risk of CWD spillover from reindeer to red deer and moose by quantifying the probability of co‐occurrence based on both (1) population density and (2) habitat niche overlap from GPS data of all three species in Nordfjella, Norway. We describe the practical challenges faced when aiming to reduce the risk of spillover through a marked reduction in the population densities of moose and red deer using recreational hunters. This involves setting the population and harvest aims with uncertain information and how to achieve them. The niche overlap between reindeer and both moose and red deer was low overall but occurred seasonally. Migratory red deer had a moderate niche overlap with the CWD‐infected reindeer population during the calving period, whereas moose had a moderate niche overlap during both calving and winter. Incorporating both habitat overlap and the population densities of the respective species into the quantification of co‐occurrence allowed for more spatially targeted risk maps. An initial aim of a 50% reduction in abundance for the Nordfjella region was set, but only a moderate population decrease of less than 20% from 2016 to 2021 was achieved. Proactive management in the form of marked population reduction is invasive and unpopular when involving species of high societal value, and targeting efforts to zones with a high risk of spillover to limit adverse impacts and achieve wider societal acceptance is important.