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Das Monitoring einheimischer Wildhuftier-Bestände ist ein grundlegendes Element des Wildtiermanagements, das in der Schweiz folgende Zielsetzungen verfolgt (gemäss Bundesgesetz über die Jagd und den Schutz wildlebender Säugetiere und Vögel JSG; SR 922.0): • den Schutz gefährdeter Arten, • dem Lebensraum angepasste Populationsgrössen mit möglichst natürlichen Bestandsstrukturen (Alters- und Geschlechterstruktur), • eine nachhaltige Jagd. Um diese Ziele zu gewährleisten bzw. verlässlich zu überprüfen, braucht es nach aktuellen Standards erhobene, gut dokumentierte Daten über Grösse, Entwicklung, Struktur, Zustand und Verbreitung von Wildtierbeständen. Zudem bilden diese Daten die Ausgangslage bei der Definition von jagdplanerischen Zielsetzungen (z.B. Stabilisierung/Senkung/Anhebung des Bestands; siehe Abb. 1) und dienen der Erfolgskontrolle bzw. Anpassung der umgesetzten Massnahmen im Sinne der rollenden Planung. Daten können mit diversen Monitoring-Methoden erhoben und analysiert werden, die sich zudem ständig weiterentwickeln. Die Arbeitsgruppe (AG) Wildhuftiere der Schweizerischen Gesellschaft für Wildtierbiologie (SGW) hat deshalb für alle im Management von Wildhuftieren tätigen Personen den vorliegenden Leitfaden erstellt. Darin werden die Parameter aufgelistet, die zur Beantwortung der wichtigsten Fragen im Huftiermanagement bekannt sein müssen, und die Monitoring-Methoden vorgestellt, die zur Erhebung dieser Parameter geeignet sind. Für jede einheimische Huftierart (Reh, Rothirsch, Wildschwein, Gämse, Steinbock) werden Empfehlungen gegeben, welche Standards ein Monitoring erfüllen soll, unter Abwägung der Aussagekraft und der Machbarkeit. Der Leitfaden entspricht dem aktuellen Wissens- und Erfahrungsstand und die Arbeitsgruppe möchte damit einen Beitrag an ein fachlich fundiertes Wildhuftiermanagement in der Schweiz leisten.

In the early 2000s, several colonies of Alpine ibex (Capra ibex ibex) in Switzerland ceased growing or began to decrease. Reproductive problems due to infections with abortive agents might have negatively affected recruitment. We assessed the presence of selected agents of abortion in Alpine ibex by serologic, molecular, and culture techniques and evaluated whether infection with these agents might have affected population densities. Blood and fecal samples were collected from 651 ibex in 14 colonies throughout the Swiss Alps between 2006 and 2008. All samples were negative for Salmonella spp., Neospora caninum, and Bovine Herpesvirus-1. Antibodies to Coxiella burnetii, Leptospira spp., Chlamydophila abortus, Toxoplasma gondii, and Bovine Viral Diarrhea virus were detected in at least one ibex. Positive serologic results for Brucella spp. likely were false. Overall, 73 samples (11.2%) were antibody-positive for at least one abortive agent. Prevalence was highest for Leptospira spp. (7.9%, 95% CI=5.0–11.7). The low prevalences and the absence of significant differences between colonies with opposite population trends suggest these pathogens do not play a significant role in the population dynamics of Swiss ibex. Alpine ibex do not seem to be a reservoir for these abortive agents or an important source of infection for domestic livestock in Switzerland. Finally, although interactions on summer pastures occur frequently, spillover from infected livestock to free-ranging ibex apparently is uncommon.

To provide baseline parasitological data for health surveillance in free-ranging Alpine ibex (Capra ibex ibex), we assessed the endoparasite population and level of parasitism in apparently healthy ibex. Faecal samples from 148 ibex were collected between 2006 and 2008 in two different Swiss ibex colonies. They were analysed by coprology, including combined sedimentation/flotation method, sedimentation method, Baermann funnel technique and Ziehl-Neelsen staining. Gastrointestinal parasites and lungworms were identified in 100% and 81.8% of the examined animals, respectively. Highest prevalences were recorded for gastrointestinal strongylids other than Nematodirus/Marshallagia spp. (100%), Eimeria spp. (100%), Muellerius spp. (79.8%) and Nematodirus/Marshallagia spp. (79.0%). We report for the first time Cryptosporidium sp. in free-ranging Alpine ibex and Cystocaulus spp. in free-ranging ibex from Switzerland. On average, ibex were infected with 3.9 different parasites taxa (range: 1-8). Parasite prevalence and diversity varied significantly between sexes, study sites and seasons. Parasite egg output was low in 95.7% and moderate in 5.3% of the samples. Overall, the results indicate that Alpine ibex are widely infected with endoparasites and suggest that multiple infections are very common in apparently healthy populations. Furthermore, our data underline the potential influence of factors such as sex, study site and season on parasitological findings.

Mycoplasma conjunctivae is considered the major cause of infectious keratoconjunctivitis (IKC) in Alpine ibex (Capra i. ibex) and chamois (Rupicapra r. rupicapra). While it is known that domestic sheep can act as healthy carriers for M. conjunctivae, this question has not been addressed in wild ungulates so far. In this study, bacteriological investigations and field observations were performed to assess whether free-ranging Alpine ibex can be healthy carriers of M. conjunctivae. Among 136 ibex without clinical signs of IKC, M. conjunctivae was identified 26 times (19.1%) by TaqMan PCR. To assess the potential pathogenicity of M. conjunctivae strains isolated from asymptomatic eyes, strains from three healthy ibex and from 15 IKC-ibex and IKC-chamois were analysed genetically by DNA sequence analysis of the variable part of the lppS gene. No significant differences were observed between strains from asymptomatic and clinically affected animals, reflecting the assumption that healthy ibex may act as carriers for M. conjunctivae strains that may be pathogenic for other individuals. Our results further indicate that development of IKC is associated with M. conjunctivae load in the eyes. In addition, a questionnaire survey revealed that IKC is generally less common in ibex than chamois and that infection in wild ungulates is not necessarily linked to the presence of sheep. These data support the hypothesis that apparently healthy ibex may be important in the epizootiology of IKC and indicate that host predilection may play a role in IKC development.

According to life-history theory age-dependent investments into reproduction are thought to co-vary with survival and growth of animals. In polygynous species, in which size is an important determinant of reproductive success, male reproduction via alternative mating tactics at young age are consequently expected to be the less frequent in species with higher survival. We tested this hypothesis in male Alpine ibex (Capra ibex), a highly sexually dimorphic mountain ungulate whose males have been reported to exhibit extremely high adult survival rates. Using data from two offspring cohorts in a population in the Swiss Alps, the effects of age, dominance and mating tactic on the likelihood of paternity were inferred within a Bayesian framework. In accordance with our hypothesis, reproductive success in male Alpine ibex was heavily biased towards older, dominant males that monopolized access to receptive females by adopting the ‘tending' tactic, while success among young, subordinate males via the sneaking tactic ‘coursing' was in general low and rare. In addition, we detected a high reproductive skew in male Alpine ibex, suggesting a large opportunity for selection. Compared with other ungulates with higher mortality rates, reproduction among young male Alpine ibex was much lower and more sporadic. Consistent with that, further examinations on the species level indicated that in polygynous ungulates the significance of early reproduction appears to decrease with increasing survival. Overall, this study supports the theory that survival prospects of males modulate the investments into reproduction via alternative mating tactics early in life. In the case of male Alpine ibex, the results indicate that their life-history strategy targets for long life, slow and prolonged growth and late reproduction

Because of a rapidly changing climate, the need to understand how populations respond to varying climatic conditions has become increasingly important. Using long-term data from an unhunted population of Alpine chamois (Rupicapra rupicapra) and autoregressive time series models we investigated the extent to which the population demography was affected by local climate. Because density and weather are likely to operate differently on various sex—age categories, anticipated effects were assumed to vary among categories. Generally, elevated densities in 1 year negatively influenced the subsequent change in population size. Severe snow conditions during late winter negatively affected total population growth, and growth of the male, yearling, and juvenile segments of the population. A lagged effect of early winter snow on the change in animal numbers was demonstrated for females. Winter temperatures positively affected the growth rate of juveniles, whereas they appeared to have negative consequences for male and yearling growth rates. The juvenile-female ratio was negatively affected by the current female density, but did not respond to the various climate variables. Winter survival of juveniles was negatively influenced by the juvenile number during the preceding summer and harsh snow conditions during early winter. Our results indicate that winter climate shapes the demography of Alpine chamois. Particularly, winters with a lot of snow might have long-lasting consequences for the population. Considering the juveniles, lagged effects apparently operate through the body condition of their mothers. The conflicting effects of temperature on the different sex—age categories make the direction of expected population response to global warming difficult to predict

In polygynous ungulates, male mortality is thought to be linked to high-energy expenditures during the rut. However, Alpine ibex (Capra ibex) adult males show an unusually high survival during this time. Male Alpine ibex live in social groups and thus, we assumed that they might reduce energy-intensive interactions during the rut by establishing, early on, strict dominance hierarchies. To evaluate this hypothesis, we studied social interactions and mating behavior in a population of Alpine ibex in the Swiss Alps. In accordance with our prediction, and in contrast to other polygynous ungulates, male Alpine ibex decreased time spent in agonistic interactions and the number of fights during the rut compared with the prerut, irrespective of their age. Changes between access-holding males always occurred without foregoing fights and were entirely based on preestablished and stable dominance relationships. Therefore, dominant males always gained and held access to receptive females and thus managed to adopt the tending tactic. Subordinate males either left the consort pair or they adopted the coursing tactic in order to achieve temporary access to estrous females. They behaved extremely reluctantly toward dominants, as they never made use of overt aggression to challenge them or to create actively transient mating opportunities. Our study supports the hypothesis that costly intramale interactions are reduced during the mating season in Alpine ibex by the adherence to preestablished and stable dominance relationships. Accordingly, male Alpine ibex appear to be able to cut down on energy expenditures, which in turn, likely contributes to their superior survival

Because of a rapidly changing climate, the need to understand how populations respond to varying climatic conditions has become increasingly important. Using long-term data from an unhunted population of Alpine chamois (Rupicapra rupicapra) and autoregressive time series models we investigated the extent to which the population demography was affected by local climate. Because density and weather are likely to operate differently on various sex—age categories, anticipated effects were assumed to vary among categories. Generally, elevated densities in 1 year negatively influenced the subsequent change in population size. Severe snow conditions during late winter negatively affected total population growth, and growth of the male, yearling, and juvenile segments of the population. A lagged effect of early winter snow on the change in animal numbers was demonstrated for females. Winter temperatures positively affected the growth rate of juveniles, whereas they appeared to have negative consequences for male and yearling growth rates. The juvenile-female ratio was negatively affected by the current female density, but did not respond to the various climate variables. Winter survival of juveniles was negatively influenced by the juvenile number during the preceding summer and harsh snow conditions during early winter. Our results indicate that winter climate shapes the demography of Alpine chamois. Particularly, winters with a lot of snow might have long-lasting consequences for the population. Considering the juveniles, lagged effects apparently operate through the body condition of their mothers. The conflicting effects of temperature on the different sex—age categories make the direction of expected population response to global warming difficult to predict

Since basic information on reproductive behaviour in male Alpine ibex was lacking, I provided in chapter 1, first a detailed description of the mating system and the two alternative mating tactics in this species. I investigated to which extent the adoption of these observed mating tactics in male Alpine ibex can contribute to the exceptional survival described in this species. Some males adopted a tactic termed ‘tending’ to monopolize individual, receptive females by following and defending them persistently against their competitors that tried to sneak copulations via the so called ‘coursing’ tactic. The adoption of the two tactics was strongly age-dependent with older males engaging primarily in the tending tactic while younger males typically used the coursing tactic. With regard to the observed copulations, tending appeared to be the more successful tactic, although some copulations were also the result of coursing. However, males adopting the coursing tactic spent more time in low-cost and less time in high-cost behaviors than males adopting the tending tactic. Time budget comparisons with another ungulate species suggested that while tending is a relatively costly tactic, coursing is a low-cost tactic that might contribute to the exceptional adult survival in male Alpine ibex. Because of the supposed small energetic costs male Alpine ibex appeared to incur during the rut and the fact that they are aggregating in social groups, I tested in chapter 2, whether energy-intensive agonistic interactions among competing males might be reduced during the rut as a result of a pre-established and binding dominance hierarchies among them. In accordance with our hypothesis, male Alpine ibex decreased the time spent in agonistic interactions and the number of horn fights during the rut compared to the pre-rut. As expected, changes between access-holding males occurred always without foregoing horn fights and were entirely based on pre-established, stable dominance relation

Wohlmeynend übersendet von Etlichen guten Gönnern und Freunden

Wohlmeynend übersendet von Etlichen guten Gönnern und Freunden

According to life-history theory age-dependent investments into reproduction are thought to co-vary with survival and growth of animals. In polygynous species, in which size is an important determinant of reproductive success, male reproduction via alternative mating tactics at young age are consequently expected to be the less frequent in species with higher survival. We tested this hypothesis in male Alpine ibex (Capra ibex), a highly sexually dimorphic mountain ungulate whose males have been reported to exhibit extremely high adult survival rates. Using data from two offspring cohorts in a population in the Swiss Alps, the effects of age, dominance and mating tactic on the likelihood of paternity were inferred within a Bayesian framework. In accordance with our hypothesis, reproductive success in male Alpine ibex was heavily biased towards older, dominant males that monopolized access to receptive females by adopting the ‘tending' tactic, while success among young, subordinate males via the sneaking tactic ‘coursing' was in general low and rare. In addition, we detected a high reproductive skew in male Alpine ibex, suggesting a large opportunity for selection. Compared with other ungulates with higher mortality rates, reproduction among young male Alpine ibex was much lower and more sporadic. Consistent with that, further examinations on the species level indicated that in polygynous ungulates the significance of early reproduction appears to decrease with increasing survival. Overall, this study supports the theory that survival prospects of males modulate the investments into reproduction via alternative mating tactics early in life. In the case of male Alpine ibex, the results indicate that their life-history strategy targets for long life, slow and prolonged growth and late reproduction

Because of a rapidly changing climate, the need to understand how populations respond to varying climatic conditions has become increasingly important. Using long-term data from an unhunted population of Alpine chamois (Rupicapra rupicapra) and autoregressive time series models we investigated the extent to which the population demography was affected by local climate. Because density and weather are likely to operate differently on various sex—age categories, anticipated effects were assumed to vary among categories. Generally, elevated densities in 1 year negatively influenced the subsequent change in population size. Severe snow conditions during late winter negatively affected total population growth, and growth of the male, yearling, and juvenile segments of the population. A lagged effect of early winter snow on the change in animal numbers was demonstrated for females. Winter temperatures positively affected the growth rate of juveniles, whereas they appeared to have negative consequences for male and yearling growth rates. The juvenile-female ratio was negatively affected by the current female density, but did not respond to the various climate variables. Winter survival of juveniles was negatively influenced by the juvenile number during the preceding summer and harsh snow conditions during early winter. Our results indicate that winter climate shapes the demography of Alpine chamois. Particularly, winters with a lot of snow might have long-lasting consequences for the population. Considering the juveniles, lagged effects apparently operate through the body condition of their mothers. The conflicting effects of temperature on the different sex—age categories make the direction of expected population response to global warming difficult to predict

In polygynous ungulates, male mortality is thought to be linked to high-energy expenditures during the rut. However, Alpine ibex (Capra ibex) adult males show an unusually high survival during this time. Male Alpine ibex live in social groups and thus, we assumed that they might reduce energy-intensive interactions during the rut by establishing, early on, strict dominance hierarchies. To evaluate this hypothesis, we studied social interactions and mating behavior in a population of Alpine ibex in the Swiss Alps. In accordance with our prediction, and in contrast to other polygynous ungulates, male Alpine ibex decreased time spent in agonistic interactions and the number of fights during the rut compared with the prerut, irrespective of their age. Changes between access-holding males always occurred without foregoing fights and were entirely based on preestablished and stable dominance relationships. Therefore, dominant males always gained and held access to receptive females and thus managed to adopt the tending tactic. Subordinate males either left the consort pair or they adopted the coursing tactic in order to achieve temporary access to estrous females. They behaved extremely reluctantly toward dominants, as they never made use of overt aggression to challenge them or to create actively transient mating opportunities. Our study supports the hypothesis that costly intramale interactions are reduced during the mating season in Alpine ibex by the adherence to preestablished and stable dominance relationships. Accordingly, male Alpine ibex appear to be able to cut down on energy expenditures, which in turn, likely contributes to their superior survival

Adult male Alpine ibex (Capra ibex ibex) have been shown to exhibit unusually high survival to relatively advanced ages (>10 years), leading to speculation that males may engage in an energetically conservative reproductive strategy that increases survival. We investigated the extent to which the adoption of alternative mating tactics contributes to the extraordinary survival of adult males in this species. Because basic information on the mating system of Alpine ibex is scarce, we 1st characterized the temporal and spatial distribution of receptive females. Our observations during 3 consecutive rutting seasons revealed 2 alternative mating tactics. Apparently dominant males monopolized individual receptive females by following and defending them, a tactic known as tending. In contrast, apparently subordinate males tried to achieve temporary access to tended females when the latter started to run, a tactic referred to as coursing. In total, 24 copulations were observed, of which 20 (83.3%) were the result of tending and 4 were the result of coursing. The adoption of the 2 tactics was strongly age-dependent; older males (9-12 years) engaged primarily in tending, whereas younger males (2-6 years) engaged mainly in coursing. Males adopting the coursing tactic spent more time in low-cost and less time in high-cost behaviors than males adopting the tending tactic. Time-budget comparisons with another ungulate species suggested that although tending is a relatively costly tactic, coursing is a low-cost tactic that may contribute to the exceptional adult survival in male Alpine ibex