Mathieu Garel's research while affiliated with Office National de la Chasse et de la Faune Sauvage and other places

Publications (125)

Article
Animals perceive human activities as risky and generally respond with fear‐induced proactive behaviors, to buffer the circadian patterns of lethal and nonlethal disturbances, such as diel migrations between risky places during safe nighttime and safer places during risky daytime. However, such responses potentially incur costs through movement or r...
Preprint
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Camera-traps have revolutionized the way ecologists monitor biodiversity and population abundances. Their full potential is however only realized when the hundreds of thousands of images collected can be rapidly classified with minimal human intervention. Machine learning approaches, and in particular deep learning methods, have allowed extraordina...
Article
Alpine mammals are highly vulnerable to current and projected climate change because they are confined to a certain elevation range. Physiological and behavioural adaptations in burrowing species, such as finding shelter in burrows when the summer conditions are unfavorable and hibernating in winter during the stressful period of resource shortage,...
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Human-mediated species dispersal across the Mediterranean stretches back at least 10,000 years and has left an indelible stamp on present-day biodiversity. Believed to be a descendant of the Asiatic mouflon (Ovis gmelini gmelinii), the Corsican mouflon (O. g. musimon) was translocated during the Neolithic as ancestral livestock by humans migrating...
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Little is known about the effects of environmental variation on allometric relationships of condition‐dependent traits, especially in wild populations. We estimated sex‐specific static allometry between horn length and body mass in four populations of mountain ungulates that experienced periods of contrasting density over the course of the study. T...
Article
Understanding the consequences of global change for animal movement is a major issue for conservation and management. In particular, habitat fragmentation generates increased densities of linear landscape features that can impede movements. While the influence of these features on animal movements has been intensively investigated, they may also p...
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The time that animals spend travelling at various speeds and the tortuosity of their movement paths are two of the many things that affect space-use by animals. In this, high turn rates are predicted to be energetically costly, especially at high travel speeds, which implies that animals should modulate their speed according to path characteristics...
Conference Paper
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Milk production and excretion may drive sex specific differences in body calcium (Ca) isotope composition, as evidenced by sheep bones collected within a single herd [1]. Such differences between sexes are however not observed in human populations [2], raising questions about Ca isotope fractionation mechanisms in mammals. We investigated this issu...
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Changes in vegetation phenology related to global warming are having alarming effects on the life history traits of many herbivore species. Such changes are particularly critical in alpine ecosystems, where strong climate limitations on plant growth make seasonal synchronization imperative for the growth, reproduction and survival of herbivores. Ho...
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The diet composition of ungulates is important to understand not only their impact on vegetation, but also to understand the consequences of natural and human-driven environmental changes on the foraging behavior of these mammals. In this work, we evaluated the use of near infrared reflectance spectroscopy analysis (NIRS), a quick, economic and non...
Article
There are clues that calcium (Ca) isotope composition of vertebrate bioapatite is influenced by diet and trophic level. These clues however conflict with several cases of mammal species exhibiting Ca isotope compositions which are inconsistent with their trophic levels. These observations support that diet may not be the only factor driving the Ca...
Article
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 w...
Article
Several individual, environmental and parasitic factors can influence the impacts of parasites on host’s fitness and on host’s ability to transmit these parasites to new hosts. Identifying these factors and the individuals who play a greater role in parasite transmission is of main concern for the development of parasite control strategies. In the...
Article
Life histories are strongly age dependent, notably linked to the onset of reproductive maturity and subsequent senescence. Consequently, ageing is predicted to impact behaviour, through the expression of either mating tactics in males or neonatal antipredator tactics in females. However, the influence of ageing, and the associated reproductive acti...
Article
Full-text available
Step selection analysis (SSA) is a fundamental technique for uncovering the drivers of animal movement decisions. Its typical use has been to view an animal as “selecting” each measured location, given its current (and possibly previous) locations. Although an animal is unlikely to make decisions precisely at the times its locations are measured, i...
Article
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Studying the factors determining the sizes of home ranges, based on bodymass, feeding style, and sociality level, is a long-standing goal at the intersection of ecology and evolution. Yet, how species-specific life history traits interact with different components of the landscape to shape differences in individual home ranges at within-population...
Article
Paleobiologists tend to use dietary information as an ecological indicator because diet is a fundamental link between an organism and its environment. However, the ecological information from fossilized hard tissues is often difficult to interpret, because links between environment, diet, and hard tissue biology are insufficiently studied in modern...
Preprint
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Animal movement paths are variously tortuous, with high turn rates predicted to be energetically costly, especially at high speeds. Animals travel most efficiently at the speed that gives the lowest cost of transport (COT), a well-defined point for movement in fluid media. However, theoretically, land animals should travel at their maximum speed to...
Preprint
Full-text available
Step selection analysis (SSA) is a fundamental technique for uncovering the drivers of animal movement decisions. Its typical use has been to view an animal as “selecting” each measured location, given its current (and possibly previous) locations. Although an animal is unlikely to make decisions precisely at the times its locations are measured, i...
Article
Full-text available
Human disturbances are rapidly increasing in northern and Arctic regions, raising concerns about the recovery and persistence of declining caribou (Rangifer tarandus) populations. Yet, the consequences of behavioral responses toward human disturbances on vital rates rarely have been investigated. Herein, we assessed the cumulative and instantaneous...
Article
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Allometric relationships describe the proportional covariation between morphological, physiological, or life‐history traits and the size of the organisms. Evolutionary allometries estimated among species are expected to result from species differences in ontogenetic allometry, but it remains uncertain whether ontogenetic allometric parameters and p...
Article
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Gastro-intestinal nematodes, especially Haemonchus contortus, are widespread pathogenic parasites of small ruminants. Studying their spatial genetic structure is as important as studying host genetic structure to fully understand host-parasite interactions and transmission patterns. For parasites having a simple life cycle (e.g., monoxenous parasit...
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How large herbivores track resource quantity and quality through time has formed the core of an abundance of literature on migratory populations in recent decades. Yet, relating foraging processes and habitat selection patterns in resident populations, where spatial heterogeneity of food resources is fine‐grained and/or where the portion of edible...
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Ticks are important vectors of several human and animal pathogens. In this study, we estimated the prevalence of important tick-borne infections in questing ticks from an area in Southwestern France (Hautes-Pyrénées) inhabited by Pyrenean chamois (Rupicapra pyrenaica pyrenaica) experiencing high tick burden. We examined adult and nymph ticks collec...
Article
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Background:Parasite infections can have substantial impacts on population dynamics and are accordingly a key challenge for wild population management. Here we studied genetic mechanisms driving parasite resistance in a large herbivore through a comprehensive approach combining measurements of neutral (16 microsatellites) and adaptive (MHC DRB1 exon...
Article
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In alpine habitats, the seasonally marked climatic conditions generate seasonal and spatial differences in forage availability for herbivores. Vegetation availability and quality during the growing season are known to drive life history traits of mountain ungulates. However, little effort has been made to understand the association between plant ph...
Article
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Decomposing the life track of an animal into behavioral segments is a fundamental challenge for movement ecology. The proliferation of high‐resolution data, often collected many times per second, offers much opportunity for understanding animal movement. However, the sheer size of modern data sets means there is an increasing need for rapid, novel...
Article
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Infectious diseases raise many concerns for wildlife and new insights must be gained to manage infected populations. Wild ungulates provide opportunities to gain such insights as they host many pathogens. Using modelling and data collected from an intensively monitored population of Pyrenean chamois, we investigated the role of stochastic processes...
Preprint
We generalize the distance sampling protocol to accommodate three types of detection data in population surveys (population counts): distance to the observer, multiple observers, and time-to-detection. We also account for the effect of a partially-observed individual covariate, with the aim to account for the non-independence of individuals in grou...
Conference Paper
Influencia del hábitat en la relación calidad-composición de la dieta en los muflones corsos.
Article
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Context In natural populations, gene flow often represents a key factor in determining and maintaining genetic diversity. In a worldwide context of habitat fragmentation, assessing the relative contribution of landscape features to gene flow thus appears crucial for sustainable management of species. Objective We addressed this issue in Mediterran...
Article
1.When they visit and revisit specific areas, animals may reveal what they need from their home range and how they acquire information. The temporal dimension of such movement recursions, i.e., periodicity, is however rarely studied, yet potentially bears a species, population, or individual‐specific signature. 2.A recent method allows estimating t...
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When modelling the distribution of animals under current and future conditions, both their response to environmental constraints and their resources’ response to these environmental constraints need to be taken into account. Here, we develop a framework to predict the distribution of large herbivores under global change, while accounting for change...
Article
Understanding the dynamics of host-pathogen interaction is key to the management of epidemics. A pestivirus belonging to the border disease virus group 4 emerged around 2001 in Pyrenean chamois (Rupicapra pyrenaica) in Spain and France. The virus had significant demographic impact in some populations, but it was less harmful and more endemic in oth...
Article
The cost of current reproduction on survival or future reproduction is one of the most studied trade-offs governing resource distribution between fitness components. Results have often been clouded, however, by the existence of individual heterogeneity, with high-quality individuals able to allocate energy to several functions simultaneously, at no...
Conference Paper
ANTECEDENTES Las condiciones climáticas en las zonas alpinas influyen sobre la biomasa vegetal y la oferta alimenticia de los herbívoros. Los ungulados de montaña adoptan estrategias biológicas para maximizar la ingesta de nutrientes y energía consumiendo las plantas más nutritivas. OBJETIVOS Describir la composición de la dieta del rebeco pirenaic...
Article
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Optimal management of free-ranging herbivores requires the accurate assessment of an animal’s nutritional status. For this purpose ‘near-infrared reflectance spectroscopy’ (NIRS) is very useful, especially when nutritional assessment is done through faecal indicators such as faecal nitrogen (FN). In order to perform an NIRS calibration, the default...
Data
Raw data containing laboratory, NIRS-predicted faecal nitrogen values and NIRS spectra values by species. (XLS)
Article
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Background Even though male-biased parasitism is common in mammals, little effort has been made to evaluate whether higher parasitic burden in males results in an extra biological cost, and thus a decrease in fitness. Body condition impairment and the augmentation of oxidative stress can be used as indicators of the cost of parasite infections. Her...
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La longueur de la patte arrière (LPA) des chevrillards est un indicateur de changement écologique (ICE) qui permet de détecter, à l’échelle d’une population, les variations de la condition physique des animaux qui la composent. Pour être opérationnel, cet ICE, comme tous les autres, doit être mesuré avec un maximum de précision. Mais qu’en est-il s...
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1. Recent advances in animal ecology have enabled identification of certain mechanisms that lead to the emergence of territories and home ranges from movements considered as unbounded. Among them, memory and familiarity have been identified as key parameters in cognitive maps driving animal navigation, but have been only recently used in empirical...
Article
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Environmental conditions experienced during early growth and development markedly shape phenotypic traits. Consequently, individuals of the same cohort may show similar life-history tactics throughout life. Conditions experienced later in life, however, could fine-tune these initial differences, either increasing (cumulative effect) or decreasing (...
Article
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Estimation of the age or age class of harvested animals is often necessary to interpret the condition and dynamics of wildlife populations. The mammalian eye lens continues to grow until death and hence the dry mass of the eye lens has commonly been used to estimate the age of mammals. The method requires the relationship between eye lens mass and...
Article
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Though it is accepted that emerging infectious diseases are a threat to planet biodiversity, little information exists about their role as drivers of species extinction. Populations are also affected by natural catastrophes and other pathogens, making it difficult to estimate the particular impact of emerging infectious diseases. Border disease vir...
Article
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In recent years, the use of satellite-derived vegetation indices has become a powerful tool to collect information on vegetation dynamics in a broad range of ecosystems worldwide. However, the utility of these indices as indicators of the diet composition and quality of herbivore mammals has not yet been established. This work focuses on exploring...
Article
1.In seasonal environments, birth dates are a central component for a species' life history, with potential long-term fitness consequences. Yet our understanding of selective pressures of environmental changes on birth dates is limited in wild mammals due to the difficulty of data collection. In a context of rapid climate change, the question of a...
Conference Paper
Resumen El objetivo del presente estudio ha sido determinar las especies de protostrongílidos presentes en la población de rebeco pirenaico (Rupicapra pyrenaica pyrenaica) de la Reserva Nacional de Caza "Freser-Setcases", mediante el análisis del aparato respiratorio de 33 rebecos abatidos durante 2012 y 2013. Procesamos los pulmones mediante cuatr...
Conference Paper
There is plenty of scientific literature showing male-biased parasitic infection in many different taxa. Hormone levels regulating the immune system and behavioral traits have been commonly associated with variations in exposure and susceptibility to pathogens, and thus in parasitic burdens. However, analysis of the physiological cost of this paras...
Article
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In many species, population dynamics are shaped by age-structured demographic parameters, such as survival, which can cause age-specific sensitivity to environmental conditions. Accordingly, we can expect populations with different age-specific survival to be differently affected by environmental variation. However, this hypothesis is rarely tested...