Deux enquêtes épidémiologiques mises en place dans les forêts de Brotonne et de Mauny, en Normandie, ont montré que la tuberculose à Mycobacterium bovis était présente à des pourcentages de prévalence importants chez les cerfs élaphes (Cervus elaphus) et les sangliers (Sus scrofa). La souche de M. bovis isolée est la même que celle qui circule dans les élevages bovins voisins depuis au moins 1995. Les sensibilité, spécificité et valeurs prédictives de l'examen nécropsique en tant qu'outil diagnostique indiquent qu'il peut être utilisé pour suivre la maladie dans les populations de cerfs élaphes où la tuberculose bovine est bien installée. La différence du cadre lésionnel entre les cerfs et les sangliers suggère que le cerf joue un rôle plus important dans la dissémination de l'infection. Un modèle déterministe montre qu'une stratégie de lutte fondée sur l'éradication des cerfs élaphes et sur un ramassage exhaustif de viscères permettrait d'obtenir une disparition de l'infection.

This thesis deals with a migration and other movements of red deer (Cervus elaphus) in the Šumava mountains. I analysed several parameters of migrations such as distance, pace, and timing of activity/movements in both sexes. I also analysed annual and daily activity rhythms and changes of daily activity during migrations and other movements.

The biological and socioeconomic feasibility of restoring elk (Cervus elaphus) to Virginia was assessed. Biological feasibility was determined by evaluating habitat suitability for elk while considering potential impacts of elk on existing fauna and flora in Virginia. Suitability was assessed by creating a habitat suitability index (HSI) model that measured the availability and accessibility of open foraging areas and forested cover areas, the availability of permanent water sources, and the degree of fragmentation by roads. Eight areas were identified as potential elk habitat: 1 in Southwest Virginia, 4 in the Shenandoah Mountains (Shenandoah, Highland, Big Meadows, Peaks of Otter), and 3 in the Southern Piedmont (Danville, Brookneal, Rehobeth). The highest potentials for supporting an elk herd were found in the Highland and Big Meadows study areas, medium biological feasibilities were found in the Southwest, Shenandoah, and Brookneal study areas, and low biological feasibilities were found in the Peaks of Otter, Danville, and Rehobeth study areas. A restored elk herd could negatively affect indigenous fauna and flora by changing the structure and diversity of existing forested ecosystems, but impacts can be minimized by maintaining elk populations at or below cultural carrying capacity. The introduction of diseases during restoration and possible transmission of those diseases from elk to humans, livestock, and other wildlife also are concerns, but these issues can be addressed by following a risk minimization protocol. Socioeconomic feasibility was assessed with a statewide mail survey of Virginia residents, 4 regional stakeholder workshops, an analysis of economic costs and benefits associated with elk restoration, and an assessment of the risks of elk-human conflicts in each of the 8 study areas. Overall, most (61%) respondents agreed that elk restoration would be good for Virginia. However, the low response rate (30%) and low confidence among respondents (49%) in their knowledge about elk indicated that most residents do not have the interest and/or necessary information to form a definitive opinion. Residents believe that the greatest benefits of restoration would be the value-based and indirect ecological benefits, such as returning an extirpated species to its native range, whereas the greatest perceived costs were the economic impacts to property, crop depredation, and public safety hazards. In contrast, local stakeholder representatives identified economic returns from increased tourism due to the presence of elk and the creation of new recreational opportunities as the most anticipated benefits; important concerns were the potential for property damage by elk, the potential impacts on local ecosystems, and the costs of implementing and administering an elk restoration program and subsequent elk management. Proposed resolutions for these issues varied by region. Representatives from the Southwest and northern Shenandoah Mountain (Shenandoah and Big Meadows study site) Regions preferred not to restore elk, whereas those from the southern Shenandoah Mountain (Highland and Peaks of Otter study site) and the Southern Piedmont Regions preferred to start out small with a carefully controlled and monitored "experimental" population. Economic benefits of elk restoration, as determined through analysis of data from other eastern states currently managing elk populations, are associated with tourism and the revenues brought to the community during elk hunting seasons, whereas economic costs are associated with crop damage, elk-vehicle collisions, and the administrative costs of managing an elk herd. Although the initial costs of transporting, releasing, and monitoring a founder population likely will exceed immediate benefits, once an elk population is established, benefits likely will exceed costs. However, an equitable distribution of costs and benefits must be devised so that the individuals who bear the costs are afforded a comparable or greater set of benefits. Risk of landowner elk-conflicts was examined by comparing human population densities and growth rates, percent private versus public land, and agricultural trends across the 8 study areas. Highest risk for elk-human conflicts was identified in the Southern Piedmont Region and in the Shenandoah study site, risk was moderate in the Southwest, Big Meadows, and Peaks of Otter study sites, and risk in the Highland study site was low. Overall, the Highland study site had the highest feasibility for elk restoration of all study areas examined; the Big Meadows and Southwest study sites both demonstrated moderate feasibility. Restoration in these areas is possible so long as management objectives remain flexible, plans are made in advance to address potential concerns, and the public is involved in the decision-making processes both before and after elk are released. / Master of Science

No / Red deer stags produce an androgen-dependent mane of long hairs only in the breeding season; in the non-breeding season, when circulating androgen levels are low, the neck hair resembles the rest of the coat. This study was designed to determine whether androgen receptors are present in deer follicles throughout the year or only in the mane (neck) follicles when circulating testosterone levels are high in the breeding season. Although androgens regulate much human hair growth the mechanisms are not well understood; they are believed to act on the hair follicle epithelium via the mesenchyme-derived dermal papilla. The location of androgen receptors in the follicle was investigated by immunohistochemistry and androgen binding was measured biochemically in cultured dermal papilla cells derived from mane and flank follicles during the breeding season and from neck follicles during the non-breeding season. Immunohistochemistry of frozen skin sections using a polyclonal antibody to the androgen receptor localised nuclear staining only in the dermal papilla cells of mane follicles. Saturation analysis assays of 14 primary dermal papilla cell lines using [(3)H]-mibolerone demonstrated high-affinity, low-capacity androgen receptors were present only in mane (breeding season neck) cells; competition studies with other steroids confirmed the specificity of the receptors. Androgen receptors were not detectable in cells from either the breeding season flank nor the non-breeding season neck follicles. The unusual biological model offered by red deer of androgen-dependent hair being produced on the neck in the breeding, but not the non-breeding season, has allowed confirmation that androgen receptors are required in follicle dermal papilla cells for an androgen response; this concurs with previous human studies. In addition, the absence of receptors in the non-breeding season follicles demonstrates that receptors are not expressed unless the follicle is responding to androgens. Androgen receptors may be induced in mane follicles by seasonal changes in circulating hormone(s).

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Changes in the abundance and distribution of free (drinking) water can influence wildlife in arid regions. In the western USA, free water is considered by wildlife managers to be important for bighorn sheep (Ovis canadensis), elk (Cervus elaphus), mule deer (Odocoileus hemionus), and pronghorn (Antilocapra americana). Nonetheless, we lack information on the influence of habitat and landscape features surrounding water sources, including wildlife water developments, and how these features may influence use of water by sexes differently. Consequently, a better understanding of differential use of water by the sexes could influence the conservation and management of those ungulates and water resources in their habitats. We deployed remote cameras at water sources to document water source use. For mule deer specifically, we monitored all known water sources on one mountain range in western Utah, during summer from 2007 to 2011 to document frequency and timing of water use, number of water sources used by males and females, and to estimate population size from individually identified mule deer. Male and female mule deer used different water sources but visited that resource at similar frequencies. On average, mule deer used 1.4 water sources and changed water sources once per summer. Additionally, most wildlife water developments were used by both sexes. We also randomly sampled 231 water sources with remote cameras in a clustered-sampling design throughout Utah in 2006 and from 2009 to 2011. In association with camera sampling at water sources, we measured several site and landscape scale features around each water source to identify patterns in ungulate use informative for managers. We used model selection to identify features surrounding water sources that were related to visitation rates for male and female bighorn sheep, elk, mule deer, and pronghorn. Top models for each species were different, but supported models for males and females of the same species generally included similar covariates, although with varying strengths. Our results highlight the differing use of water sources by the sexes. This information will help guide managers when siting and reprovisioning wildlife water developments meant to benefit those species, and when prioritizing natural water sources for preservation or enhancement.

The capture of neonate ungulates has played an integral role in studies of habitat selection, phenology, survival, and other topics of ecological interest. However, neonates can be difficult for researchers to locate and capture. Neonate ungulates are born in habitats with reduced visibility, frequently spend time in a concealed, prone position, and may display cryptic coloration. In an attempt to improve researchers' likelihood of locating and capturing neonate ungulates, multiple capture methods have been developed. Much remains unknown about biases associated with capture methods and how to further improve capture methods once biases are understood. Our objectives were to determine if opportunistic captures of neonate mule deer (Odocoileus hemionus) bias estimates of litter size (Chapter 1) and to determine when searches for neonate elk (Cervus canadensis) should begin following parturition to maximize likelihood of capture while minimizing disturbance (Chapter 2). To complete our objectives, we analyzed data from 161 litters of mule deer and 55 attempted captures of neonate elk during 2019-2021 in Utah, USA. Estimates of litter size derived from opportunistic captures of mule deer were smaller than estimates derived from movement-based captures or captures completed with the aid of vaginal implant transmitters (VITs). The time elapsed between parturition and when searches were initiated for neonate mule deer did not influence estimates of litter size, but we could only analyze this relationship for VIT-aided captures within approximately 2 days of parturition. Until more data are available, we recommend that estimates of litter size for neonate mule deer be completed using movement-based or VIT-aided captures within approximately 2 days of parturition. When attempting to capture neonate elk, reducing the time elapsed between parturition and when searches were initiated resulted in a decreased search length, decreased distance traveled by the neonate, and increased likelihood of capture. We initiated searches as early as 3.6 hours post-parturition with no evidence of maternal abandonment and probability of capture was near or above 90% when searches were initiated within 10 hours of parturition. We recommend that searches for neonate elk be initiated 3.6-10 hours post-parturition. Future researchers can use utilize our results to perform captures of neonate ungulates that minimize bias, decrease disturbance, increase efficiency, and maximize the likelihood of capture success.

Quoi de plus naturel qu’une clôture ? Parmi les images d’Epinal qui nous viennent spontanément à l’esprit, le bocage avec ses haies bien ordonnées, évoque une relation apaisée, rationnelle, arcadienne avec une nature nourricière et bienveillante. Pourtant, la prolifération des clôtures en milieu rural depuis un siècle a suscité la curiosité de nombreux chercheurs dans des disciplines variées. Qu’il s’agisse de protéger la nature de dégradations engendrées par les populations humaines - dans le cas d’espaces protégés -, ou à l’inverse de protéger les humains contre des dangers « naturels » - comme dans le cas de la prévention routière, ces clôtures semblent répondre à une nécessité absolue de ségrégation spatiale entre les hommes et la nature : Quoi de moins naturel qu’une clôture ? Vu sous cet angle, le conflit politico-environnemental engendré par la propagation récente des engrillagements forestiers en Sologne reflète assez bien l’ambiguïté de nos perceptions vis-à-vis du caractère naturel ou non de ces clôtures. La Sologne est une région naturelle Française couvrant près de 500 000 hectares délimitée au nord par la vallée de la Loire et au sud par la vallée du Cher. Fruit d’une occupation humaine attestée depuis le XIe siècle, conjuguée à des contraintes écologiques spécifiques, le paysage Solognot est aujourd’hui caractérisé par son couvert boisé important (environ 50% de la surface) et ses populations importantes de grand gibier, qui entretiennent la longue réputation cynégétique de cette région ; la propriété privée y est largement majoritaire (plus de 90% de la surface forestière). En 2012, une agitation médiatique (film, articles de presse, sites internet) cristallisent un conflit environnemental latente, faisant intervenir des éléments écologiques – les effets supposés bénéfiques ou néfastes de ces engrillagements sur la grande faune, mais aussi politiques – la nécessité de réglementer les engrillagements, et culturels - la sauvegarde du « paysage Solognot ». Afin d’analyser ce conflit, une approche interdisciplinaire de type Political Ecology a été menée, mêlant travail d’enquête auprès de la population et étude du fonctionnement écologique des espaces engrillagés. Ces travaux ont montré que les engrillagements modifient la répartition spatiale des cerfs. La recherche d’effets cascades sur les oiseaux forestiers - résultants des surdensités locales de cerfs en espace engrillagé - n’a cependant pas mis en évidence d’effet négatif. A partir des enquêtes, il apparaît que le conflit est pluridimensionnel et que l’aspect écologique – bien réel – ne suffit pas à lui seul pour comprendre l’enjeu de ce débat au sujet des engrillagements. Ces résultats génèrent une réflexion sur la complexité des conflits environnementaux, et la nécessité d’envisager ces conflits sous des angles différents. Cela implique d’utiliser des outils et des approches issues de plusieurs disciplines, mais aussi et surtout de parvenir à mettre en résonance le matériel hétérogène ainsi obtenu, afin de proposer une approche multifacette mais cohérente. Dans ce cas d’étude, les résultats sur les effets cascades se sont par exemple révélés extrêmement marginaux, alors qu’une étude parallèle sur le comportement du sanglier en milieu engrillagé aurait probablement été très pertinente. Cela amène plus largement à réfléchir sur le « cadrage » des problèmes environnementaux, et sur les choix conscients ou non que nous faisons lorsque nous décrivons une situation comme problématique pour « la nature ». Plus généralement, ces résultats incitent à (re)placer le politique au cœur de nos réflexions sur ce qu’est la « nature », y compris dans la façon dont nous écologues posons nos questions de recherches. / What could be more natural than a fence? Among the traditional images in our collective heritage, a pastoral landscape with well maintained hedges evokes a calm, rational, Arcadian relationship between man and a benevolent, sustaining ature. Yet the century-long proliferation of fences in our rural landscapes has attracted the curiosity of numerous researchers from a variety of disciplines. Whether the goal is to protect nature from the degradations caused by human populations - as in the case of natural protected areas, or inversely, to protect humans from “natural” dangers – as in the case of accident prevention and road safety, fences seem to respond to a primordial necessity to segregate man and nature in space: What could be less natural than a fence? With this in mind, the political/environmental conflict over the recent propagation of forest fences in Sologne reflects quite well the ambiguity of how we perceive such fences – or they “natural” or not? The Sologne is an officially designated “natural region” in France. It extends over nearly 500,000 hectares bordered on the North by the Loire valley and on the South by the Cher valley. The Sologne landscape is the fruit of human occupation, certain since the XI century, combined with specific ecological constraints. Today, Sologne is characterized by extensive forest cover (around 50% of the surface area) and by large populations of big game animals, maintaining the region’s a long history of hunting. Furthermore, land ownership in Sologne is mainly private and more than 90% of the forested area is in private holdings. In 2012, some media excitement (film, newspaper articles, internet sites) crystallized an environmental conflict calling on ecological arguments – the supposed beneficial or detrimental effects of the fencing networks on big game, but also on political arguments – the need to regulate these networks, and on cultural arguments – preserving the Sologne landscape. In order to disentangle the structural lines of this conflict, we applied an interdisciplinary, Political Ecology approach; we combined opinion polls among the inhabitants with the study of ecological functions within the fenced zones. We observed that fences induced modifications of deer habitat use. However, our investigations into a possible cascade effect on forest birds resulting from localized deer over-population in fenced areas revealed no evidence of any negative impact. From our opinion polls, we found that the conflict seems to be multi-dimensional and that the ecological aspect – whose existence is indeed supported by fact – is not sufficient alone to understand what is at stake in this fencing dispute. Our results highlight the complexity of environmental conflicts, and the importance of viewing these conflicts from many different angles. Apprehending this complexity implies using tools and approaches from several different disciplines, but also – and above all – making the heterogeneous results obtained resonate together, in order to propose a coherent, multi-facetted approach. In this study for example, the results obtained for potential cascade effects on birds were extremely marginal, whereas a parallel study on wild boar behavior patterns in an environment with a fencing network would probably have been very pertinent. This leads us to the broader question of the “framework” of environmental problems and to the question of the choices we make – whether consciously or not – when we describe a situation as detrimental to “Nature”. More generally, the results from this study encourage us to put politics (back) into the center of our reflections surrounding the question: What is nature? – and to keep this in mind when we as ecologists define our research hypotheses.

Fasioloides magna is a trematode parasitizing in the liver parenchyma of ruminants. Its life cycle is associated with the humid environment and includes intermediate freshwater snail hosts from family Lymnaeidae. According to the ability of host to form a certain type of a pseudocyst during fascioloidosis, they can be,divided in three groups, specific definitive hosts (red deers, fallow deers, roe deers), nonspecific definitive hosts (cattle, wild boars and elks) and atypical hosts (sheeps and goats). Beside the natural infections also the experimental infections of other potential host species has been realized (chamois, llama and bighorn sheep and traditional laboratory animals such as mice, guinea pigs, rats and rabbits). In the context of different diseases, many changes in infected organism can occur. These can be qualitatively and quantitatively evaluated. Similarly, during fascioloidosis the changes associated with the presence of the parasite in the host's body is possible to monitor, e.g. antibody production, increase in the number of eosinophils, release of eggs in faeces, internal bleeding, or the level liver damage. The liver damage is corresponding primarily to biochemical parameters of blood, not only the liver enzymes, but also other blood components, like blood proteins, lipids,...

The eco-epidemiology of bovine tuberculosis (Tb) in wild deer (mainly red deer Cervus elaphus) in New Zealand was investigated. Bovine Tb is caused by Mycobacterium bovis. Specific aims were to clarify the likely routes of infection in deer, and to determine the status of deer as hosts of Tb, the likely rates and routes of inter- and intra-species transmission between deer and other wildlife hosts, the role of deer in spreading Tb, and the likely utility of deer as sentinels of Tb presence in wildlife. As the possum (Trichosurus vulpecula) is the main wildlife host of Tb, the research also included some investigation of transmission routes in possums. Patterns of infection were measured in 994 deer killed between 1993 and 2003. Tb prevalence varied between areas (range 8–36%). Few deer had generalised infection, with 21–68% of infected deer having no visible lesions, depending on the area. The retropharyngeal lymph nodes and oropharyngeal tonsils were commonly infected. No dependent fawns less than 0.75 years old were infected, indicating intra-species transmission is rare in wild deer. Where possums were not controlled, the net (cumulative) force of infection in young (1–4 y) deer was 0.10–0.24 per year in males and 0.09–0.12 per year in females, but much lower in older deer (less than 0.05 per year). Possum control reduced the net force of infection quickly, and eventually to zero. However, Tb persisted in possum-controlled areas through immigration of infected deer and, for almost a decade, through the survival of resident deer infected before possum control. Tb was lost from infected deer at an exponential rate of 0.13 per year, mostly as a result of deer recovering from infection rather than dying from it. Wild deer do die of Tb, but there was no discernible effect on age structure. The occurrence of infection in deer was not linked to the local deer or possum density at their kill sites (i.e. in their home range), but the area-wide prevalence of Tb in deer was closely correlated with Tb levels in possums, which were in turn correlated with area-wide measures of possum density. For wild deer in New Zealand, Tb is a persistent but usually inconsequential disease of the lymphatic system. It is acquired mainly by young independent deer, usually orally via the tonsils, and probably as a result of licking infected possums. Many species fed on deer carrion, including possums. Most possums encountering carrion did not feed on it, but a few fed for long periods. Other scavengers such ferrets (Mustela furo), hawks (Circus approximans), and weka (a hen-sized flightless native bird; Gallirallus australis) fed in a way that probably increased the infectivity of carrion to possums. Commercial deer hunting may have facilitated the historical establishment of Tb in possums. Scavenging (including cannibalism) and interactions with dead and dying possums are identified for the first time as potentially important routes for transmission of Tb to possums, and I develop new hypotheses involving peri- and post-mortem transmission in possums that explain many of the epidemiological patterns that are characteristic of the disease in possum. In continuous native forest, deer home range size averaged 250 hectares for six young females, and over twice that for two males. Over 90% of infected deer are likely to die within 2 km (females) or 6 km (males) of where they acquired Tb, but deer could occasionally carry Tb up to 30 km. Deer will be useful as sentinels, but only where other sentinels are rare, because the force of infection for a deer with a single infected possum in its home range is only 0.004 per year, compared to greater than 0.2 per year for deliberately released pigs. Deer are occasionally capable of initiating new cycles of infection in wildlife, but deer control is not essential to eradicate Tb from wildlife.