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In variable environments, habitats that are rich in resources often carry a higher risk of predation. As a result, natural selection should favour individuals that balance allocation of time to foraging versus avoiding predation through an optimal decision-making process that maximizes fitness. The behavioural trade-off between resource acquisition and risk avoidance is expected to be particularly acute during gestation and lactation, when the energetic demands of reproduction peak. Here, we investigated how reproductive female roe deer adjust their foraging activity and habitat use during the birth period to manage this trade-off compared with non-reproductive juveniles, and how parturition date constrains individual tactics of risk-resource management. Activity of reproductive females more than doubled immediately following parturition, when energy demand is highest. Furthermore, compared with non-reproductive juveniles, they increased their exposure to risk by using open habitat more during daytime and ranging closer to roads. However, these post-partum modifications in behaviour were particularly pronounced in late-parturient females who adopted a more risk-prone tactic, presumably to compensate for the growth handicap of their late-born offspring. In income breeders, individuals that give birth late may be constrained to trade risk avoidance for foraging during peak allocation to reproduction, with probable consequences for individual fitness. [ABSTRACT FROM AUTHOR]

Accurate heritability estimates for fitness‐related traits are required to predict an organism's ability to respond to global change. Heritability estimates are theoretically expected to be inflated if, due to limited dispersal, individuals that share genes are also likely to share similar environments. However, if relatives occupy similar environments due, at least partly, to genetic variation for habitat selection, then accounting for environmental similarity in quantitative genetic models may result in diminished heritability estimates in wild populations. This potential issue has been pointed out in the literature, but has not been evaluated by empirical studies.Here, we investigate whether environmental similarity among individuals can be partly explained by genetic variation for habitat selection, and how this link potentially blurs estimates for heritability in fitness‐related traits.Using intensive GPS monitoring, we quantified home‐range habitat composition for 293 roe deer inhabiting a heterogeneous landscape to assess environmental similarity. To investigate if environmental similarity might harbour genetic variation, we combined genome‐wide data in a quantitative genetic framework to evaluate genetic variation for home‐range habitat composition, which is partly the result of habitat selection at settlement. Finally, we explored how environmental similarity affects heritability estimates for behaviours related to the risk avoidance–resource acquisition trade‐off (i.e. being in open habitat and distance to roads) and proxies of individual performance (i.e. body mass and hind foot length). We found substantial heritability for home‐range habitat composition, with estimates ranging from 0.40 (proportion of meadows) to 0.85 (proportion of refuge habitat). Accounting for similarity in habitat composition between relatives decreased the heritability estimates for both behavioural and morphological traits (reduction ranging from 55% to 100% and from 22% to 41% respectively). As a consequence, only half of these heritability estimates remained significantly different from zero.Our results show that similar genotypes occupy similar environments, which could lead to heritable variation being incorrectly attributed to environmental effects. To accurately distinguish the sources of phenotypic variation and predict the ability of organisms to respond to global change, it is necessary to develop quantitative genetic studies investigating the mechanisms underpinning environmental similarity among relatives. [ABSTRACT FROM AUTHOR]

The timing of birth has a predominant influence on both the reproductive success of the mother and the life‐history trajectory of her offspring. Because early growth and survival are key drivers of population dynamics, there is an urgent need to understand how global change is affecting reproductive phenology and performance. However, identifying when and where birth occurs is often difficult in the wild due to the cryptic behaviour of females around parturition, although this information may also help managers to protect reproductive females and newborn against human disturbance. While several approaches to identify parturition based on movement metrics derived from GPS monitoring have previously been proposed, their performance has not been evaluated over a range of species with contrasted movement characteristics.Here, we present a novel approach to detect parturition by combining data on animal movements, activity rate and habitat use. Using machine learning approaches, we evaluated the relative and combined performance of each category of metrics in predicting parturition for three large herbivores with contrasted life histories: a hider‐type species, the roe deer Capreolus capreolus and two follower‐type species, the Mediterranean mouflon Ovis gmelini musimon × Ovis sp. and the Alpine ibex Capra ibex.We first showed that detection of parturition was much improved when birth‐related modifications in the habitat use and activity rate of the mother were considered, rather than relying on movement metrics only. We then demonstrated that our approach was highly successful (76%–100% of events correctly identified) in detecting parturition in both follower and hider species. Furthermore, our approach generated estimates for peak birth date and the proportion of parturient females that were comparable with those based on direct observations at the population scale. Finally, our approach outperformed the most commonly employed methods in the literature which generally failed to identify non‐reproductive females for the three studied species, and provided birth timing estimates that only poorly match the true parturition date.We suggest that by combining sources of information, we have developed a standardised methodological approach for inferring parturition in the wild, not only for large herbivores but also for any species where parturition induces marked behavioural changes in the mother. [ABSTRACT FROM AUTHOR]

In Europe, ticks are major vectors of both human and livestock pathogens (e.g. Lyme disease, granulocytic anaplasmosis, bovine babesiosis). Agricultural landscapes, where animal breeding is a major activity, constitute a mosaic of habitat types of various quality for tick survival and are used at different frequencies by wild and domestic hosts across seasons. This habitat heterogeneity, in time and space, conditions the dynamics of these host-vector-pathogen systems and thus drives acarological risk (defined as the density of infected ticks). The principal objective of the OSCAR project (2011-2016) was to examine the links between this heterogeneity and acarological risk for humans and their domestic animals. Here, we present the data associated with this project. [ABSTRACT FROM AUTHOR]

Assessing the evolutionary potential of animal populations in the wild is crucial to understanding how they may respond to selection mediated by rapid environmental change (e.g. habitat loss and fragmentation). A growing number of studies have investigated the adaptive role of behaviour, but assessments of its genetic basis in a natural setting remain scarce. We combined intensive biologging technology with genome‐wide data and a pedigree‐free quantitative genetic approach to quantify repeatability, heritability and evolvability for a suite of behaviours related to the risk avoidance‐resource acquisition trade‐off in a wild roe deer (Capreolus capreolus) population inhabiting a heterogeneous, human‐dominated landscape. These traits, linked to the stress response, movement and space‐use behaviour, were all moderately to highly repeatable. Furthermore, the repeatable among‐individual component of variation in these traits was partly due to additive genetic variance, with heritability estimates ranging from 0.21 ± 0.08 to 0.70 ± 0.11 and evolvability ranging from 1.1% to 4.3%. Changes in the trait mean can therefore occur under hypothetical directional selection over just a few generations. To the best of our knowledge, this is the first empirical demonstration of additive genetic variation in space‐use behaviour in a free‐ranging population based on genomic relatedness data. We conclude that wild animal populations may have the potential to adjust their spatial behaviour to human‐driven environmental modifications through microevolutionary change. [ABSTRACT FROM AUTHOR]

Although inter‐individual heterogeneity in many aspects of dispersal behaviour is widely reported, this key life‐history trait is predominantly modelled as a dichotomous state of philopatry versus dispersal. The increasing body of evidence for dispersal syndromes (i.e. a suite of correlated morphological, behavioural and life‐history traits associated with dispersal) implies substantial but, to date, undocumented individual heterogeneity in behavioural tactics during dispersal. Using a large sample (n = 154) of GPS monitored juvenile roe deer Capreolus capreolus, we evaluated among‐individual behavioural heterogeneity in dispersal tactics, and the individual and environmental drivers of these alternative tactics. We developed a sequential three‐stage decision tree based on space use stability, exploration events and the directionality of movement. We identified six discrete alternative behavioural tactics during the dispersal period which were characterised by different timing, amplitude and duration in movement: slightly less than half of the deer were sedentary, either 'strictly philopatric' or 'explorers', which subsequently settled on their natal range; around 40% dispersed ('classic dispersal'), of which, one in six subsequently aborted, moving back to their natal range ('aborted dispersal'); finally, around 15% expressed either a 'progressive dispersal' tactic, gradually moving away from their natal area to settle elsewhere, or a 'multi‐range' tactic. The propensity to express an alternative dispersal tactic was strongly influenced by an individual's local environment. In particular, when landscape heterogeneity, resource quality and human‐related disturbance in the natal range were low, individuals were 1) more likely to adopt the alternative tactics of either progressive dispersal or multi‐ranging, but 2) also more likely to abort their dispersal attempt. Our work indicates that natal dispersal is likely not a single uniform behaviour, but that individuals may adopt a variety of alternative movement tactics which are likely governed by different selection pressures, with potentially important impacts for population dynamics and functioning. [ABSTRACT FROM AUTHOR]

Wildlife populations are increasingly exposed to human-induced modifications of their habitats. To cope with anthropogenic stressors, animals can adjust their behaviour—for example, by shifting their activity to more sheltered habitats, or becoming more nocturnal. However, whether use of spatial and temporal adjustments in behaviour may regulate the endocrine response is poorly documented. Here, we analyzed faecal cortisol metabolites (FCMs) of wild roe deer (Capreolus capreolus) living in a human-dominated agro-ecosystem. Using Global Positioning System monitoring of 116 individuals, we assessed their spatial behaviour and tested whether proximity to anthropogenic structures (linear distance to built-up areas) and the use of refuge habitats (woodland and hedges) influenced FCM levels. In accordance with our predictions, individuals ranging closer to anthropogenic structures during daytime had higher FCM levels, but this relationship was buffered as use of refuge habitat increased. In addition, this link between proximity to anthropogenic structures and FCM levels disappeared when we analyzed spatial behaviour at night. Finally, FCM levels were higher when the ambient temperature was lower, and during years of low resource availability. Our results demonstrate that the stress levels of large mammals may be strongly influenced by their proximity to anthropogenic activities, but that these effects may be buffered by behavioural adjustments in terms of space use and circadian rhythm. Whereas most studies have focused on the influence of environmental heterogeneity, our analysis highlights the need to also consider the fine-scale spatial response of individuals when studying the hormonal response of wild animals to human disturbance. We emphasize the potential to mitigate this hormonal stress response, and its potential negative consequences on population dynamics, through the preservation or restoration of patches of refuge habitat in close proximity to human infrastructure. [ABSTRACT FROM AUTHOR]

Dispersal is a key mechanism enabling species to adjust their geographic range to rapid global change. However, dispersal is costly and environmental modifications are likely to modify the cost–benefit balance of individual dispersal decisions, for example, by decreasing functional connectivity.Dispersal costs occur during departure, transience and settlement, and are levied in terms of energy, risk, time and lost opportunity, potentially influencing individual fitness. However, to the best of our knowledge, no study has yet quantified the energetic costs of dispersal across the dispersal period by comparing dispersing and philopatric individuals in the wild.Here, we employed animal‐borne biologgers on a relatively large sample (N = 105) of juvenile roe deer to estimate energy expenditure indexed using the vector of dynamic body acceleration and mobility (distance travelled) in an intensively monitored population in the south‐west of France. We predicted that energy expenditure would be higher in dispersers compared to philopatric individuals. We expected costs to be (a) particularly high during transience, (b) especially high in the more fragmented areas of the landscape and (c) concentrated during the night to avoid disturbance caused by human activity.There were no differences in energy expenditure between dispersers and philopatric individuals during the pre‐dispersal phase. However, dispersers expended around 22% more energy and travelled around 63% further per day than philopatric individuals during transience. Differences in energy expenditure were much less pronounced during the settlement phase. The costs of transience were almost uniquely confined to the dawn period, when dispersers spent 23% more energy and travelled 112% further than philopatric individuals. Finally, the energetic costs of transience per unit time and the total distance travelled to locate a suitable settlement range were higher in areas of high road density.Our results provide strong support for the hypothesis that natal dispersal is energetically costly and indicate that transience is the most costly part of the process, particularly in fragmented landscapes. Further work is required to link dispersal costs with fitness components so as to understand the likely outcome of further environmental modifications on the evolution of dispersal behaviour. [ABSTRACT FROM AUTHOR]

A procedure using Differential Global Positioning System (DGPS) technology to successfully study fine-scale selection of wild mammals is given. It is demonstrated that long intervals between fixes could cause a loss of information for the shortest activity bouts, which make up around 5 and 11.5% of the daily budget using 10- and 15-min fix intervals, respectively.

Dispersal is a key life-history trait governing the response of individuals, populations and species to changing environmental conditions. In the context of global change, it is therefore essential to better understand the respective role of condition-, phenotype- and genetic-dependent drivers of dispersal behaviour. Although the importance of immune function and pathogen infestation in determining patterns of dispersal is increasingly recognised, no study to our knowledge has yet investigated the influence of immune gene variability on dispersal behaviour. Here, we filled this knowledge gap by assessing whether individual heterozygosity at five immune gene loci (one from the Major histocompatibility complex and four from encoding Toll-like receptors) influences roe deer natal dispersal. We found that dispersal propensity was affected by immune gene diversity, suggesting potential pathogen-mediated selection through over-dominance. However, the direction of this effect differed between high and low quality individuals, suggesting that dispersal propensity is driven by two different mechanisms. In support of the condition-dependent dispersal hypothesis, dispersal propensity increased with increasing body mass and, among high quality individuals only (standardized body mass > 18 kg), with increasing immune gene diversity. However, among poor quality individuals, we observed the opposite pattern such that dispersal propensity was higher for individuals with lower immune gene diversity. We suggest that these poor quality individuals expressed an emergency dispersal tactic in an attempt to escape a heavily infested environment associated with poor fitness prospects. Our results have potentially important consequences in terms of population genetics and demography, as well as host-pathogen evolution. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the accuracy of GPS 3300 to predict active (feeding, moving) and inactive (bedded, standing) behaviours in European roe deer. Observed activity of three tame roe deer was correlated with the three variables provided by the activity sensors of their collars (normalised for each individual) using discriminant analyses. The best model discriminated correctly 84% of the 'active' time intervals (defined as roe deer spending at least 30% of the time active) and 97% of inactive ones. We tested for consistency with movements using 11 wild roe deer, six living in a forest and five in an open habitat. As expected, wild deer identified as inactive (sensors) were mostly immobile (GPS locations, 831 records of 1096), whereas deer known to be moving were mostly classified as active (493 of 758 records). The records classified as inactive but moving (24% of inactive records or 35% of moving records) can indicate short distance displacement, erroneous detection of movement, or moving without neck movements. The records classified as active but immobile (46% of active ones, 33% of immobile ones) can represent feeding on a small patch without detectable movements. [ABSTRACT FROM AUTHOR]

The article focuses on a study that investigated whether the capture and handling of roe deer Capreolus capreolus, a medium-sized ungulate, modified its space use, activity and habitat use immediately following release. It cites the effect of capture stress on mortality, biological or physiological parameters and reproduction. It mentions the approach used by the researchers to study the immediate, short-term effects of capture on the spatial behaviour of roe deer. It details the impact of landscape structure on the degree of post-capture homerange displacement.

Here we present the first description of the vocal behaviour of the Tyrrhenian subspecies of Red Deer, the Corsican Deer. Vocalisations from calves, hinds and stags were recorded. Their acoustic characteristics were analysed in order to contrast these with published data characterising central European Red Deer hind and calve contact calls and Scottish Red Deer stag mating calls. We found that the vocal repertoire of Corsican Deer was very comparable with that of central European and Scottish Red Deer, with the exception of one call type, the harsh roar, absent in the Corsican Deer repertoire. Because Corsican Deer are the smallest subspecies of Red Deer, we expected calls to be characterised by higher spectral components. However, while male roars did have higher vocal tract resonances, consistent with a shorter vocal tract, we found that the fundamental frequency (F0) was much lower than predicted, in fact the lowest recorded in any studied Red Deer subspecies. We also found a strong sexual dimorphism in F0, with male calls approximately twice as low as female calls, suggesting that the low F0 observed in Corsican male roars is a result of sexual selection for lower-pitched males. The results of this study emphasise the phenotypic originality of Corsican Deer, and strengthen the case for its conservation. We also argue that future studies should compare the vocal behaviour of Corsican Deer with that of other circum-Mediterranean populations. [ABSTRACT FROM AUTHOR]

Bouts of vocalizations given by seven red deer stags were recorded over the rutting period, and homomorphic analysis and hidden Markov models (two techniques typically used for the automatic recognition of human speech utterances) were used to investigate whether the spectral envelope of the calls was individually distinctive. Bouts of common roars (the most common call type) were highly individually distinctive, with an average recognition percentage of 93.5%. A “temporal” split-sample approach indicated that although in most individuals these identity cues held over the rutting period, the ability of the models trained with the bouts of roars recorded early in the rut to correctly classify later vocalizations decreased as the recording date increased. When Markov models trained using the bouts of common roars were used to classify other call types according to their individual membership, the classification results indicated that the cues to identity contained in the common roars were also present in the other call types. This is the first demonstration in mammals other than primates that individuals have vocal cues to identity that are common to the different call types that compose their vocal repertoire. [ABSTRACT FROM AUTHOR]

Abstract: During the development of mammals, skeletal growth is an informative measure of homeostasis between environmental conditions and individual anabolism. Young animals are more sensitive to adverse conditions than adults because they invest the majority of their resources in somatic growth. Here, by means of a manipulative experience, we aim to explore the effect of density oscillations on skeletal development as measured by the age of ossification and the total length of the metacarpus in juvenile fallow deer (Dama dama Linneaus, 1758) inhabiting an enclosure (south-western France). Our results show that, for animals born at high density, the total length of the metacarpus was lower on average by about 11.2mm for females and 9mm for males compared to animals born in low-density conditions. Furthermore, we observed that the age of ossification of both sexes was earlier in animals that experienced high density during early growth (5.8 months for females and 7.7 months for males at high density versus 12 and 12.8 months, respectively at low density). The total length of metacarpi and the age of ossification did not differ between the sexes in both high- and low-density periods. We conclude that the length of bones and the age at which animals achieve total ossification is sensitive to changes in animal''s density, probably because of density-dependent competition for resources. [Copyright &y& Elsevier]

Anaplasma phagocytophilum is a bacterial pathogen mainly transmitted by Ixodes ricinus ticks in Europe. It infects wild mammals, livestock, and, occasionally, humans. Roe deer are considered to be the major reservoir, but the genotypes they carry differ from those that are found in livestock and humans. Here, we investigated whether roe deer were the main source of the A. phagocytophilum genotypes circulating in questing I. ricinus nymphs in a fragmented agricultural landscape in France. First, we assessed pathogen prevalence in 1837 I. ricinus nymphs (sampled along georeferenced transects) and 79 roe deer. Prevalence was dramatically different between ticks and roe deer: 1.9% versus 76%, respectively. Second, using high-throughput amplicon sequencing, we characterized the diversity of the A. phagocytophilum genotypes found in 22 infected ticks and 60 infected roe deer; the aim was to determine the frequency of co-infections. Only 22.7% of infected ticks carried genotypes associated with roe deer. This finding fits with others suggesting that cattle density is the major factor explaining infected tick density. To explore epidemiological scenarios capable of explaining these patterns, we constructed compartmental models that focused on how A. phagocytophilum exposure and infection dynamics affected pathogen prevalence in roe deer. At the exposure levels predicted by the results of this study and the literature, the high prevalence in roe deer was only seen in the model in which superinfections could occur during all infection phases and when the probability of infection post exposure was above 0.43. We then interpreted these results from the perspective of livestock and human health. [ABSTRACT FROM AUTHOR]

Because avoiding predation is crucial for fitness, foraging animals must trade acquisition of high-quality resources against risk avoidance when the best resources occur in locations with high predation risk. Although optimality models predict the distance at which an animal should initiate vigilance and flight, many studies have shown that animals generally flee soon after detecting an approaching threat, supporting the ‘flush early and avoid the risk’ (FEAR) hypothesis. Despite this, flight behaviour varies markedly depending on context, suggesting some behavioural plasticity in the response of prey to a given threat. We evaluated the degree of plasticity in the flight responses of roe deer, Capreolus capreolus , a highly flexible species which thrives in human-dominated landscapes. Based on individually identifiable animals and a standardized flight initiation protocol, we measured the distance at which a deer detected an approaching threat, and the distance at which it subsequently initiated flight. Our results provide strong support for the FEAR hypothesis, suggesting that alert and flight responses are strongly coupled in roe deer. However, the perceived level of both risk (in terms of landscape openness and proximity to human infrastructure) and reward (in terms of habitat quality) influenced the time it took for a deer to detect an approaching threat, and the subsequent time for which the threat was tolerated prior to flight. Overall, our findings indicate that although roe deer minimize monitoring costs when assessing risk by fleeing early, they also adjust their monitoring and flight responses to the local risk–resource trade-off. [ABSTRACT FROM AUTHOR]

The mortality risk from hunting/predation should increase animals'' vigilance and modify their selection of feeding sites. This risk may thus be costly if vigilance interferes with feeding and/or if animals select poorer but safer feeding sites. We observed the vigilance behaviour of roe deer, Capreolus capreolus, feeding in a fragmented landscape during and outside the hunting season and compared food availability and local landscape features at these feeding sites with random paired sites. Roe deer spent more time vigilant during the hunting season than outside it. During the hunting season, vigilance decreased as the woodland extent within an 800m radius increased, but this was not the case outside the hunting season. Vigilance decreased with increasing distance to houses, both during and outside the hunting season. When food is abundant, interference with feeding may be low because animals can simultaneously process food (chewing) and be vigilant. During the hunting season, the total time spent vigilant while chewing increased with increasing food abundance to a lesser extent than outside the hunting season, suggesting a higher level of costly exclusive vigilance during the hunting season. Outside the hunting season animals selected feeding sites that provided more food, but during the hunting season, as risk (proximity to houses) was positively correlated with food availability, animals no longer selected feeding sites on the basis of food availability. Taken together, our results indicate that roe deer trade off risk avoidance for food availability in hunted populations. [Copyright &y& Elsevier]

Abstract: In gregarious ruminants, females and males tend to live in separate groups outside the rutting season. According to the ‘activity budget’ hypothesis, this is due to an activity asynchrony between the two sexes reducing the lifetime of mixed-sex groups. We tested this hypothesis in a fallow deer population. Activity asynchrony was more frequent in mixed-sex than in single-sex groups. In addition, mixed-sex groups had a higher probability of splitting-up than all-female groups, and they mainly split up into single-sex groups. However, activity asynchrony did not appear as a major cause of splitting-up. To cite this article: N. Villerette et al., C. R. Biologies 329 (2006). [Copyright &y& Elsevier]