Analyzing long-term impacts of ungulate herbivory on forest-recruitment dynamics at community and species level contrasting tree densities versus maximum heights.

Herbivores are constitutive elements of most terrestrial ecosystems. Understanding effects of herbivory on ecosystem dynamics is thus a major, albeit challenging task in community ecology. Effects of mammals on plant communities are typically explored by comparing plant densities or diversity in exclosure experiments. This might over-estimate long-term herbivore effects at community levels as early life stage mortality is driven by a multitude of factors. Addressing these challenges, we established a set of 100 pairs of ungulate exclosures and unfenced control plots (25 m2) in mixed montane forests in the Alps in 1989 covering a forest area of 90 km2. Investigations ran until 2013. Analogous to the gap-maker-gap-filler approach, dynamically recording the height of the largest trees per tree species in paired plots with and without exclosures might allow for assessing herbivore impacts on those individuals with a high probability of attaining reproductive stages. We thus tested if recording maximum heights of regenerating trees would better reflect effects of ungulate herbivory on long-term dynamics of tree regeneration than recording of stem density, and if species dominance patterns would shift over time. For quantifying the effects of ungulate herbivory simultaneously at community and species level we used principle response curves (PRC). PRCs yielded traceable results both at community and species level. Trajectories of maximum heights yielded significant results contrary to trajectories of total stem density. Response patterns of tree species were not uniform over time: e.g., both Norway spruce and European larch switched in their response to fencing. Fencing explained about 3% of the variance of maximum tree heights after nine years but increased to about 10% after 24 years thus confirming the importance of long-term surveys. Maximum height dynamics of tree species, addressed in our study, can thus reflect local dominance of tree species via asymmetric plant competition. Such effects, both within and among forest patches, can accrue over time shaping forest structure and composition.

Different effects of alpine woody plant expansion on domestic and wild ungulates.

Changes in land-use and climate affect the distribution and diversity of plant and animal species at different spatiotemporal scales. The extent to which species-specific phenotypic plasticity and biotic interactions mediate organismal adaptation to changing environments, however, remains poorly understood. Woody plant expansion is threatening the extent of alpine grasslands worldwide, and evaluating and predicting its effects on herbivores is of crucial importance. Here, we explore the impact of shrubification on the feeding efficiency of Pyrenean chamois (Rupicapra p. pyrenaica), as well as on the three most abundant coexisting domestic ungulate species: cattle, sheep and horses. We use observational diet composition from May to October and model different scenarios of vegetation availability where shrubland and woodland proliferate at the expense of grassland. We then predicted if the four ungulate species could efficiently utilize their food landscapes with their current dietary specificities measuring their niche breath in each scenario. We observed that the wild counterpart, due to a higher trophic plasticity, is less disturbed by shrubification compared to livestock, which rely primarily on herbaceous plants and will be affected 3.6 times more. Our results suggest that mixed feeders, such as chamois, could benefit from fallow landscapes, and that mountain farmers are at a growing economic risk worldwide due to changing land-use practices and climate conditions.

Seasonal diet composition of Pyrenean chamois is mainly shaped by primary production waves.

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 phenology and changes in the foraging strategies of these mountain dwellers. Furthermore, this link can be affected by the seasonal presence of livestock in the same meadows. The objective of this work was to study the seasonal changes in diet composition of Pyrenean chamois (Rupicapra p. pyrenaica) and its relationship to primary production trends in a Mediterranean alpine environment. Moreover, diet composition in two populations with contrasting livestock pressure was compared in order to study the effect of sheep flocks on the feeding behaviour of chamois. From 2009 to 2012, monthly diet composition was estimated by cuticle microhistological analysis of chamois faeces collected in the eastern Pyrenees. The primary production cycle was assessed by remote sensing, using the Normalized Difference Vegetation Index. Additionally, the diet of sheep sharing seasonally the subalpine and alpine meadows with chamois was analysed. Diet selection of chamois and sheep and their overlap was also assessed. Our results show an intra-annual variation in the diet composition of Pyrenean chamois and demonstrate a strong relationship between plant consumption dynamics and phenology in alpine areas. In addition, Calluna vulgaris, Cytisus spp. and Festuca spp., as well as forbs in the summer, are found to be key forage species for Pyrenean chamois. Furthermore, this study couldn't detect differences between both chamois populations despite the presence of sheep flocks in only one area. However, the detection of a shift in the diet of chamois in both areas after the arrival of high densities of multi-specific livestock suggest a general livestock effect. In conclusion, Pyrenean chamois are well adapted to the variations in the seasonal availability of plants in alpine habitats but could be disturbed by the seasonal presence of livestock. Due to the key plants in their diet, we suggest that population management programmes should focus on the preservation of mixed grasslands composed of patches of shrubs and herbs. The effects of climate change and shrub expansion should be studied as they may potentially affect chamois population dynamics through changes in habitat composition and temporal shifts in forage availability.

From gestation to weaning: Combining robust design and multi-event models unveils cost of lactation in a large herbivore.

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 apparent cost. Surprisingly, it has also rarely been assessed within a breeding season by breaking down the various reproductive efforts of females from gestation to weaning, even though resource availability and energy requirements vary greatly. We filled this gap by using an intensively monitored population of Pyrenean chamois and by expanding a new methodological approach integrating robust design in a multi-event framework. We distinguished females that gave birth or not, and among reproducing females whether they lost their kid or successfully raised it until weaning. We estimated spring and summer juvenile survival, investigated whether gestation, lactation or weaning incurred costs on the next reproductive occasion, and assessed how individual heterogeneity influenced the detection of such costs. Contrary to expectations if trade-offs occur, we found a positive relationship between gestation and adult survival suggesting that non-breeding females are in poor condition. Costs of reproduction were expressed through negative relationships between lactation and both subsequent breeding probability and spring juvenile survival. Such costs could be detected only once individual heterogeneity (assessed as two groups contrasting good vs. poor breeders) and time variations in juvenile survival were accounted for. Early lactation decreased the probability of future reproduction, providing quantitative evidence of the fitness cost of this period recognized as the most energetically demanding in female mammals and critical for neonatal survival. The new approach employed made it possible to estimate two components of kid survival that are often considered practically unavailable in free-ranging populations, and also revealed that reproductive costs appeared only when contrasting the different stages of reproductive effort. From an evolutionary perspective, our findings stressed the importance of the temporal resolution at which reproductive cost is studied, and also provided insights on the reproductive period during which internal and external factors would be expected to have the greatest fitness impact.

Nocturnal activity of a "diurnal" species, the northern chamois, in a predator-free Alpine area.

The reduction of predation risk is widely considered a major factor affecting the nocturnal activity of mammals. Furthermore, on precipitous mountain terrain, moving in very poor light conditions should be avoided by animals with no special eyesight adaptation to darkness. The Northern chamois Rupicapra rupicapra has been for long considered as a diurnal species, with occasional nocturnal movements. For the first time, we have quantified the nocturnal activity of 21 radiotagged female chamois from the Italian Eastern Alps (Paneveggio-Pale di San Martino Natural Park), continuously monitored for two years from sunset to sunrise, with 24h tracking sessions carried out for six months. Large predators were not present in the study site. Despite their mainly diurnal activity pattern, peaks of nocturnal movements were detected throughout the year. The least proportion of active night fixes occurred in January and in July, while the most were in April and in October. The greater nocturnal activity in the warm months compared to cold periods, was probably due to frozen snow cover reducing nocturnal movements. Movements were mainly concentrated in bright moonlight nights, possibly because of the absence of large predators, but more likely because of increased visibility. Changes in activity levels throughout the year may also reflect changes in energy requirements of Northern chamois.

Tall Grass Invasion After Grassland Abandonment Influences the Availability of Palatable Plants for Wild Herbivores: Insight into the Conservation of the Apennine Chamois Rupicapra pyrenaica ornata.

Invasion of the tall grass Brachypodium genuense was observed in an area of the central Apennines (Italy) where the population size of Apennine chamois (Rupicapra pyrenaica ornata) was in strong decline. Since this dominant tall grass threatens biodiversity and forage quality, our hypothesis was that B. genuense abundance influenced that of palatable species for the chamois, depending on their functional traits and distribution patterns. Our sampling design used plots of 10 × 10 m and 1 × 1 m to investigate the plant community level and fine-scale interactions. We analyzed data using correlation, generalized linear models, and redundancy analyses. We found that B. genuense can reach high abundance values on the deepest soils. Its high cover value influences plant community composition by competitive exclusion of subordinate species and suppression of functional features because of temporal or spatial niche overlap. This leads to low cover of palatable species at a fine scale, and to poor pasture quality for chamois at a wider scale. Therefore, we postulated that B. genuense invasion, enhanced by long-term grazing cessation, may reduce the availability of palatable plants for Apennine chamois, especially below the potential timberline (1900-2000 m a.s.l.). The high abundance of B. genuense may amplify the effect of other negative factors, such as competition with red deer (Cervus elaphus) and climate change, in restricting the suitable habitat of the Apennine chamois to the higher sectors of the central Apennines. Thus, we suggested that B. genuense spread should be monitored carefully and plans to control its invasion should be implemented.

Heterogeneity in Primary Productivity Influences Competitive Interactions between Red Deer and Alpine Chamois.

Habitat heterogeneity can promote coexistence between herbivores of different body size limited to different extents by resource quantity and quality. Red deer (Cervus elaphus) are known as superior competitors to smaller species with similar diets. We compared competitive interactions and habitat use between red deer and Alpine chamois (Rupicapra rupicapra) in two adjacent valleys in a strictly protected area in the Central Alps. Red deer density was higher in the valley with higher primary productivity. Only here was horn growth in kid and yearling chamois (as a measure for body condition) negatively correlated with red deer population size, suggesting interspecific competition, and chamois selected meadows with steeper slopes and lower productivity than available on average. Conversely, red deer selected meadows of high productivity, particularly in the poorer area. As these were located mainly at lower elevations, this led to strong altitudinal segregation between the two species here. Local differences in interspecific competition thus coincided with differences in habitat preference and-segregation between areas. This suggests that spatial habitat and resource heterogeneity at the scale of adjacent valleys can provide competition refuges for competitively inferior mountain ungulates which differ from their superior competitor in their metabolic requirements.

Onset of autumn shapes the timing of birth in Pyrenean chamois more than onset of spring.

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 possible mismatch between plant phenology and birth phenology also remains unanswered for most species. We assessed whether and how the timing of birth in a mountain mammal (isard, also named Pyrenean chamois, Rupicapra pyrenaica pyrenaica) tracked changes in plant growing season, accounting for maternal traits, individual heterogeneity and population density. We not only focused on spring conditions but also assessed to what extent onset of autumn can be a driver of phenological biological events and compared the magnitude of the response to the magnitude of the environmental changes. We relied on a 22-year study based on intensively monitored marked individuals of known age. Births were highly synchronized (80% of kids born within 25 days) and highly repeatable (84%; between-female variation of 9.6 days, within-female variation of 4.2 days). Individual phenotypic plasticity allows females to respond rapidly to interannual changes in plant phenology but did not prevent the existence of a mismatch: a 10-day advance in the autumn or spring plant phenology led to 3.9 and 1.3 days advance in birth dates, respectively. Our findings suggest that plant phenology may act as a cue to induce important stages of the reproductive cycle (e.g. conception and gestation length), subsequently affecting parturition dates, and stressed the importance of focusing on long-term changes during spring for which females may show much lower adaptive potential than during autumn. These results also question the extent to which individual plasticity along with high heterogeneity among individuals will allow species to cope with demographic consequences of climate changes.

Age-specific survival and annual variation in survival of female chamois differ between populations.

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 at the intra-specific level. Using capture-mark-recapture models, we quantified age-specific survival and the extent of annual variations in survival of females of alpine chamois in two sites. In one population, survival was very high (>0.94; Bauges, France) until the onset of senescence at approximately 7 years old, whereas the two other populations (Swiss National Park, SNP) had a later onset (12 years old) and a lower rate of senescence. Senescence patterns are therefore not fixed within species. Annual variation in survival was higher in the Bauges (SD = 0.26) compared to the SNP populations (SD = 0.20). Also, in each population, the age classes with the lowest survival also experienced the largest temporal variation, in accordance with inter-specific comparisons showing a greater impact of environmental variation on these age classes. The large difference between the populations in age-specific survival and variation suggests that environmental variation and climate change will affect these populations differently.

A novel epidemiological model to better understand and predict the observed seasonal spread of Pestivirus in Pyrenean chamois populations.

Seasonal variations in individual contacts give rise to a complex interplay between host demography and pathogen transmission. This is particularly true for wild populations, which highly depend on their natural habitat. These seasonal cycles induce variations in pathogen transmission. The seasonality of these biological processes should therefore be considered to better represent and predict pathogen spread. In this study, we sought to better understand how the seasonality of both the demography and social contacts of a mountain ungulate population impacts the spread of a pestivirus within, and the dynamics of, this population. We propose a mathematical model to represent this complex biological system. The pestivirus can be transmitted both horizontally through direct contact and vertically in utero. Vertical transmission leads to abortion or to the birth of persistently infected animals with a short life expectancy. Horizontal transmission involves a complex dynamics because of seasonal variations in contact among sexes and age classes. We performed a sensitivity analysis that identified transmission rates and disease-related mortality as key parameters. We then used data from a long-term demographic and epidemiological survey of the studied population to estimate these mostly unknown epidemiological parameters. Our model adequately represents the system dynamics, observations and model predictions showing similar seasonal patterns. We show that the virus has a significant impact on population dynamics, and that persistently infected animals play a major role in the epidemic dynamics. Modeling the seasonal dynamics allowed us to obtain realistic prediction and to identify key parameters of transmission.

Upscaling the niche variation hypothesis from the intra- to the inter-specific level.

The "niche variation hypothesis" (NVH) predicts that populations with wider niches should display higher among-individual variability. This prediction originally stated at the intra-specific level may be extended to the inter-specific level: individuals of generalist species may differ to a greater extent than individuals of a specialist species. We tested the NVH at intra- and inter-specific levels based on a large diet database of three large herbivore feces collected in the field and analyzed using DNA metabarcoding. The three herbivores (roe deer Capreolus capreolus, chamois Rupicapra rupicapra and mouflon Ovis musimon) are highly contrasted in terms of sociality (solitary to highly gregarious) and diet. The NVH at the intraspecific level was tested by relating, for the same population, diet breadth and inter-individual variation across the four seasons. Compared to null models, our data supported the NVH both at the intra- and inter-specific levels. Inter-individual variation of the diet of solitary species was not larger than in social species, although social individuals feed together and could therefore have more similar diets. Hence, the NVH better explained diet breadth than other factors such as sociality. The expansion of the population niche of the three species was driven by resource availability, and achieved by an increase in inter-individual variation, and the level of inter-individual variability was larger in the generalist species (mouflon) than in the specialist one (roe deer). This mechanism at the base of the NVH appears at play at different levels of biological organization, from populations to communities.

Senescence in breeding success of female Alpine chamois (Rupicapra rupicapra): the role of female quality and age.

Although numerous studies have reported reproductive senescence in wild animal populations, we still know very little on inter-individual differences in rates of ageing and on the factors accounting for these differences. To investigate age-related variation in breeding success in a natural population of Alpine chamois (Rupicapra rupicapra), we used 15 years of data obtained by monitoring individual ear-tagged females. Analyses at the population level confirmed the occurrence of a decline in female breeding success, which is most noticeable from 9 years of age onward. Using an age-reverse approach, we showed that senescence in female breeding success occurs at the same age, since only very old individuals (older than 16 years) showed a decline in breeding success in the years preceding death. Interestingly, we also found evidence that 'success comes from success', as females that gave birth in a given year were more likely to procreate again in the following year. Moreover, results showed that discrepancies between successful and unsuccessful individuals tend to become more relevant in the oldest age classes. There was no evidence of a terminal allocation. These results emphasize the importance of age-dependent effects and individual quality in shaping reproductive senescence in a wild long-lived ungulate.

Physiological response to etho-ecological stressors in male Alpine chamois: timescale matters!

From a life history perspective, glucocorticoids secreted by the neuroendocrine system, integrating different sources of stress through an adaptive feedback mechanism, may have important consequences on individual fitness. Although stress responses have been the object of several investigations, few studies have explored the role of proximate mechanisms responsible for the potential trade-offs between physiological stress and life history traits integrating social and environmental stressors. In 2011 and 2012, we collected data on faecal cortisol metabolites (FCM) in a marked male population of Alpine chamois, within the Gran Paradiso National Park (Italy). Using a model selection approach we analysed the effect of potential etho-ecological stressors such as age, social status (territorial vs. non-territorial males), minimum temperature, snow depth and precipitation on FCM variation. To correctly interpret environmentally and socially induced stress responses, we conducted model selections over multiple temporal scales defined a priori: year, cold months, spring, warm months, mating season. Over the year, FCM levels showed a negative relationship with minimum temperature, but altogether, climatic stressors had negligible effects on glucocorticoid secretion, possibly owing to good adaptations of chamois to severe weather conditions. Age was negatively related to FCM during the rut, possibly due to greater experience of older males in agonistic contests. Social status was an important determinant of FCM excretion: while both the 'stress of subordination' and the 'stress of domination' hypotheses received some support in spring and during the mating season, respectively, previous data suggest that only the latter may have detrimental fitness consequences on male chamois.

Rutting behaviour of territorial and nonterritorial male chamois: is there a home advantage?

Males using alternative male mating tactics (AMTs) may express their mating effort in a variety of ways. In polygynous species with limited sexual dimorphism, differences in male aggressiveness may affect mating opportunities. We recorded the behaviour of 8 territorial and 7 nonterritorial male Alpine chamois Rupicapra rupicapra, a nearly monomorphic ungulate, during the 2011 rut in the Gran Paradiso National Park (Italy), to analyse differences in mating effort and mating opportunities between AMTs. The chamois showed a rich behavioural repertoire (31 behavioural patterns), with a prevalence of indirect aggression. Territorial males had higher frequency of aggressive and courtship behaviour than nonterritorial males over the early rut. Later, nonterritorials increased their mating effort, possibly because of reduced competition with dominant males. Territorial males monopolised all observed mating events. Our results support the hypothesis that chamois may assert dominance through intense aggressiveness rather than through horn size or body mass as found in other polygynous ungulates. Most important, differences in mating effort mediated by AMTs resulted in different mating opportunities; these benefits, however, are traded off against greater costs, due to higher levels of hormone metabolites and parasitism. Data on AMTs flexibility, lifetime reproductive success and survival are needed to clarify the mechanisms underlying the evolution and maintenance of AMTs within chamois populations.

Intraseasonal variation in reproductive effort: young males finish last.

Age-dependent reproductive timing has been observed in females of a number of species; older females often breed earlier in the season and experience higher reproductive success as a result. However, to date, evidence for within-season variation in reproductive effort (RE) for males has been relatively weak. Males are expected to time RE in light of intraseasonal variations in the availability of receptive females and competition with other males. Young males, which are typically smaller and less experienced, might benefit from breeding later in the season, when male-male competition is less intense. Using a long-term data set of Alpine chamois Rupicapra rupicapra, we sought to evaluate the hypothesis that younger males allocate highest RE late in the breeding season, at a time when older male RE has decreased substantially. Our results support this hypothesis, which suggests that intraseasonal variation in RE may be an adaptive life-history trait for males as well as females.

Effect of acepromazine and haloperidol in male Iberian Ibex (Capra pyrenaica) captured by box-trap.

Short-acting neuroleptic drugs are used to prevent adverse effects of stress in wildlife. We compared the effect of acepromazine and haloperidol in Iberian ibex (Capra pyrenaica) captured with box-traps. We captured 23 male Iberian ibex at the National Game Reserve of Ports de Tortosa i Beseit, northeastern Spain, March 2003-June 2005. Seven animals received 0.1 mg/kg of acepromazine maleate, eight received 0.33 mg/kg of haloperidol and eight animals acted as controls. Clinical, hematologic, and serum biochemical parameters were analyzed. Both treatments decreased rectal temperature, white blood cells, lymphocytes, and concentrations of creatinine, creatine kinase, and lactate dehydrogenase. Acepromazine also decreased red blood cells, packed cell volume, hemoglobin concentration, neutrophils, and concentrations of glucose and cholesterol. Haloperidol also decreased heart rate and concentrations of urea and potassium. Our results demonstrate the suitability of using acepromazine and haloperidol in capture operations to reduce stress and prevent its adverse effects.

Contrasting life histories in neighbouring populations of a large mammal.

BACKGROUND: A fundamental life history question is how individuals should allocate resources to reproduction optimally over time (reproductive allocation). The reproductive restraint hypothesis predicts that reproductive effort (RE; the allocation of resources to current reproduction) should peak at prime-age, whilst the terminal investment hypothesis predicts that individuals should continue to invest more resources in reproduction throughout life, owing to an ever-decreasing residual reproductive value. There is evidence supporting both hypotheses in the scientific literature. METHODOLOGY/PRINCIPAL FINDINGS: We used an uncommonly large, 38 year dataset on Alpine chamois (Rupicapra rupicapra) shot at various times during the rutting period to test these two hypotheses. We assumed that body mass loss in rutting males was strongly related to RE and, using a process-based approach, modelled how male relative mass loss rates varied with age. For different regions of our study area, we provide evidence consistent with different hypotheses for reproductive allocation. In sites where RE declined in older age, this appears to be strongly linked to declining body condition in old males. In this species, terminal investment may only occur in areas with lower rates of body mass senescence. CONCLUSIONS/SIGNIFICANCE: Our results show that patterns of reproductive allocation may be more plastic than previously thought. It appears that there is a continuum from downturns in RE at old age to terminal investment that can be manifest, even across adjacent populations. Our work identifies uncertainty in the relationship between reproductive restraint and a lack of competitive ability in older life (driven by body mass senescence); both could explain a decline in RE in old age and may be hard to disentangle in empirical data. We discuss a number of environmental and anthropogenic factors which could influence reproductive life histories, underlining that life history patterns should not be generalised across different populations.

Effects of early horn growth on reproduction and hunting mortality in female chamois.

1. Environmental conditions during early development can affect the growth patterns of vertebrates, influencing future survival and reproduction. In long-lived mammals, females that experience poor environmental conditions early in life may delay primiparity. In female bovids, annual horn growth increments may provide a record of age-specific reproduction and body growth. Horn length, however, may also be a criterion used by hunters in selecting animals to harvest, possibly leading to artificial selection. 2. We studied three populations of chamois (Rupicapra rupicapra) in the western Alps to explore the relationships between female horn length and early growth, age of primiparity and age-specific reproduction. We also compared the risk of harvest to reproductive status and horn length. 3. Early horn growth was positively correlated with body mass in pre-reproductive females and with reproduction in very young and senescent adults. Females with strong early horn growth attained primiparity at an earlier age than those with weak early growth. Horn length did not affect hunter selection, but we found a strong hunter preference for nonlactating females. 4. Our research highlights the persistent effects of early development on reproductive performance in mammals. Moderate sport harvests are unlikely to affect the evolution of phenotypic traits and reproductive strategies in female chamois. A policy of penalizing hunters that harvest lactating females, however, may increase the harvest of 2-year-old females, which have high reproductive potential.

Haloperidol and azaperone in drive-net captured Southern chamois (Rupicapra pyrenaica).

We investigated the effect of haloperidol and azaperone in drive-net captured Southern chamois (Rupicapra pyrenaica). Both tranquilizers have been successfully used in a wide range of wild species for reducing postcapture stress response. During 2005, 39 free-ranging chamois were captured, randomly injected intramuscularly with haloperidol (0.29 +/- 0.12 mg/kg; n=24), azaperone (1.1 +/- 0.82 mg/kg; n=6), or saline (0.5 ml; n=9), and restrained for 3 hr. Heart rate was higher in the treated chamois; erythrocyte parameters and total protein concentration decreased over time owing to splenic sequestration, hemodilution, vasodilation, and reflex tachycardia. Creatinine, sodium, and chloride remained stable only in the haloperidol-treated group, suggesting an improvement in renal perfusion. Nevertheless, the azaperone-treated chamois displayed higher body temperature, and both treated groups had higher serum muscular enzymes than the control group, suggesting higher muscle stress. These results lead us not to recommend the use of these tranquilizers-especially azaperone-as first-choice neuroleptics in chamois.

An SEI model for sarcoptic mange among chamois.

We consider a simple model to study the dynamics of sarcoptic mange in a population of chamois. The epidemiological patterns observed during an epidemic in Italy are reconstructed and key parameters of the model are estimated from field data. In particular, we calculate the basic reproductive ratio R (0), a threshold value for chamois density for the occurrence of an epidemic and the speed of propagation of the epidemic wave. The model is then used to obtain indications on the effect of culling as a possible control measure in a closed population and extended to analyse the spatial diffusion of the epidemic. Our results are in agreement with mange epidemiology and observations, and suggest that intervention could be efficacious in reducing the impact of an epidemic.