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Bruno Bassano - One of the best experts on this subject based on the ideXlab platform.
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Climate forcing and density dependence in a mountain ungulate population. Ecology 2004
2020Co-Authors: Andrew R. Jacobson, Achaz Von Hardenberg, Antonello Provenzale, Bruno Bassano, Marco Festa-bianchetAbstract:Abstract. Population models in ecology are rarely validated by comparing their predictions to long-term observations of changes in population size. We have used a variety of analytical tools to examine a 45-year time series of annual censuses of Alpine Ibex (Capra Ibex) in the Gran Paradiso National Park in northwestern Italy. This Ibex population grew from about 3300 to almost 5000 individuals in the 1980s during a decade of anomalously mild winters, and then began to decline in the 1990s. By 1997, the population size had returned to previous levels. Adult survival apparently increased and adult sex ratio may have changed to slightly favor males during the increase in population density. Yearly changes in total population were correlated with seasonal average snow depth and population density over the 39 years for which climate data were available. Our results show that the Ibex population size was limited by both density dependence and deep snow. A model based on these factors fit to the first 19 years of data was used to forecast subsequent changes in total population based on initial population size and yearly snow depth. The model was able to predict the increase and subsequent decline in total population size over the final 20 years of the study but failed to reproduce population levels after the eruption. Our results suggest that the 1980s episode of population growth was primarily driven by increased adult survival, rather than increased recruitment
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heterozygosity fitness correlation at the major histocompatibility complex despite low variation in alpine Ibex Capra Ibex
Evolutionary Applications, 2018Co-Authors: Alice Brambilla, Bruno Bassano, Lukas F Keller, Christine GrossenAbstract:Crucial for the long‐term survival of wild populations is their ability to fight diseases. Disease outbreaks can lead to severe population size reductions, which makes endangered and reintroduced species especially vulnerable. In vertebrates, the major histocompatibility complex (MHC) plays an important role in determining the immune response. Species that went through severe bottlenecks often show very low levels of genetic diversity at the MHC. Due to the known link between the MHC and immune response, such species are expected to be at particular risk in case of disease outbreaks. However, so far, only few studies have shown that low MHC diversity is correlated with increased disease susceptibility in species after severe bottlenecks. We investigated genetic variation at the MHC and its correlations with disease resistance and other fitness‐related traits in Alpine Ibex (Capra Ibex), a wild goat species that underwent a strong bottleneck in the last century and that is known to have extremely low genetic variability, both genome‐wide and at the MHC. We studied MHC variation in male Ibex of Gran Paradiso National Park, the population used as a source for all postbottleneck reintroductions. We found that individual MHC heterozygosity (based on six microsatellites) was not correlated with genome‐wide neutral heterozygosity. MHC heterozygosity, but not genome‐wide heterozygosity, was positively correlated with resistance to infectious keratoconjunctivitis and with body mass. Our results show that genetic variation at the MHC plays an important role in disease resistance and, hence, should be taken into account for successfully managing species conservation.
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brain lesions associated with infectious kerato conjunctivitis in chamois and alpine Ibex
Journal of Mountain Ecology, 2014Co-Authors: Bruno Bassano, V Peracino, Elisabeth Bollo, Fabiana GuardaAbstract:Twenty-five Chamois (RupiCapra rupiCapra) and 8 Alpine Ibex (Capra Ibex Ibex) with infectious keratoconjunctivitis were captured in the Gran Paradiso National Park. Only seven chamois and 4 alpine Ibex showed signs of nervousness. The histopatological findings showed that 12 chamois and 4 Ibex were affected by inflammatory alterations of the brain, represented by: foci of nono-purulent leptomeningitis as small accumulations of mononuclear cells; perivascular cuffings in the cerebral hemispheres; severe infiltration of lymphocytes in the choroid plexus fo the cerebral ventricles. The non-purulent morphology of the inflammation might be a consequence of the action of the primary pathogenic agent (Mycoplasma, Chlamydia or Rickettsia).
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don t spit in the soup faecal avoidance in foraging wild alpine Ibex Capra Ibex
Animal Behaviour, 2013Co-Authors: Alice Brambilla, Achaz Von Hardenberg, Bruno Bassano, Ornella Kristo, Giuseppe BoglianiAbstract:Faeces are a major vehicle for transmission of parasites among ungulate hosts. Avoiding feeding in proximity to faeces has been shown to be an antiparasitic strategy in experimental settings with domestic and semidomestic ungulates. However, few studies have tested the faecal avoidance hypothesis in wild herbivores. We tested the faecal avoidance hypothesis in a wild population of Alpine Ibex by comparing the quantity of faeces in grazed and avoided areas. We counted faecal pellets within a plot around a grazing individual and a plot around a spot actively avoided by the same individual. As predicted, grazed plots had lower densities of faecal pellets than avoided plots. Fresh faeces were avoided more often than medium-aged and old faeces. We found consistent differences in the level of faecal avoidance among individuals, but this was not related to the level of gastrointestinal parasite infection or to the age of the host. Our results suggest that wild Alpine Ibex actively avoid foraging near faeces but the antiparasitic value of this behaviour is not evident.
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temperature constraints on foraging behaviour of male alpine Ibex Capra Ibex in summer
Oecologia, 2009Co-Authors: Jeanfrancois Aublet, Marco Festabianchet, Domenico Bergero, Bruno BassanoAbstract:In arctic and alpine environments, warm sum- mer temperatures may force a reduction in foraging time of large herbivores, whose tolerance for heat is lower than for species adapted to warmer weather. We constructed time budgets for marked Ibex (Capra Ibex) males over two sum- mers to test whether warm temperatures constrained forag- ing behaviour and forced altitudinal migrations. As daily temperature and solar radiation increased, feeding activity was reduced at midday and evening, but increased in the early morning, probably to anticipate for an expected reduction in foraging later in the day. With increasing tem- perature and solar radiation, Ibex moved to higher eleva- tions where they spent very little time feeding. Changes in forage quality and availability could not explain altitudinal migration. Temperatures above 15-20°C apparently result in heat discomfort in male Alpine Ibex. As temperature and solar radiation increased, older and larger Ibex spent less time feeding during daylight and showed a steeper decrease in feeding time than younger and smaller Ibex. Larger males may be more sensitive to temperature and solar radi- ation, or may have more Xexibility in allocating time to diVerent activities, given their lower relative energetic requirements.
B. Bassano - One of the best experts on this subject based on the ideXlab platform.
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Cohabitation of a Brucella melitensis infected Alpine Ibex (Capra Ibex) with domestic small ruminants in an enclosure in Gran Paradiso National Park, in Western Italian Alps
European Journal of Wildlife Research, 2007Co-Authors: E. Ferroglio, M. S. Gennero, M. Pasino, S. Bergagna, A. Dondo, C. Grattarola, M. Rondoletti, B. BassanoAbstract:After the first report of Brucella melitensis infection from a 7-year-old alpine Ibex ( Capra Ibex ) buck living in Gran Paradiso National Park (GPNP), further studies demonstrated the presence of the infection in Ibex and chamois. Considering that livestock herds keep on sharing pastures with more than 3,500 Ibex and 9,000 chamois in the park, our aim was to demonstrate under controlled conditions the possibility of Brucella infection passing from wild ruminants to livestock. A 7-year-old male alpine Ibex with clinical signs of brucellosis and serologically positive was released in a 5,000 m^2 enclosure together with five goats and two sheep rams. Due to poor condition, Ibex was suppressed at day 40, domestic ruminants stayed into the enclosure potentially contaminated by Ibex for further 38 days. During this period, we had monitored our animals taking blood from domestic ruminants every 15 days and tested the serum to Rose Bengal agglutination test and Complement Fixation test. Domestic animals tested negative at serology at all sampling time and at isolation, while B. melitensis biovar 3 was isolated from Ibex tissues. Our data show that transmission of infection from Ibex to livestock is not easy. After 40 days of strict cohabitation and 38 days of permanence in an area where an infected Ibex lives, no one of the domestic animals contracted infection. In spite of the limitation of our field trial, we have demonstrated that long direct and indirect contact between alpine Ibex and domestic animals will not easily lead to an infection of the latter. Further investigations are needed to confirm our results and evaluate the effective risk of B. melitensis transmission from alpine Ibex to livestock.
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Age-dependent genetic effects on a secondary sexual trait in male Alpine Ibex, Capra Ibex
Molecular Ecology, 2007Co-Authors: A Von Hardenberg, Marco Festa-bianchet, B. Bassano, G. Luikart, P. Lanfranchi, D. ColtmanAbstract:Secondary sexual traits, such as horns in ungulates, may be good indicators of genetic quality because they are costly to develop. Genetic effects on such traits may be revealed by examining correlations between multilocus heterozygosity (MLH) and trait value. Correlations between MLH and fitness traits, termed heterozygosity-fitness correlations (HFC), may reflect inbreeding depression or associative overdominance of neutral microsatellite loci with loci directly affecting fitness traits. We investigated HFCs for horn growth, body mass and faecal counts of nematode eggs in wild Alpine Ibex (Capra Ibex). We also tested if individual inbreeding coefficients (f') estimated from microsatellite data were more strongly correlated with fitness traits than MLH. MLH was more strongly associated with trait variation than f'. We found HFC for horn growth but not for body mass or faecal counts of nematode eggs. The effect of MLH on horn growth was age-specific. The slope of the correlation between MLH and yearly horn growth changed from negative to positive as males aged, in accordance with the mutation accumulation theory of the evolution of senescence. Our results suggest that the horns of Ibex males are an honest signal of genetic quality.
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Microsatellite DNA and recent statistical methods in wildlife conservation management: applications in Alpine Ibex [Capra Ibex (Ibex)]
Molecular Ecology, 2002Co-Authors: C. Maudet, Christian Miller, B. Bassano, C. Breitenmoser-wursten, D. Gauthier, G. Obexer-ruff, J. Michallet, P. Taberlet, G. LuikartAbstract:We evaluated the usefulness of microsatellites and recently developed statistical methods for the conservation management of fragmented and reintroduced populations, using the alpine Ibex (Capra Ibex) as a model species. First, we assessed the effects of past reintroduction programmes on genetic diversity and population differentiation considering different population sizes and histories. We show that genetic variability in Ibex populations (H-E approximate to 0.13) is among the lowest reported from microsatellites in mammal species, and that the Alpi Marittime-Mercantour population has suffered from a severe genetic bottleneck associated with its reintroduction. Second, using a computer-simulation approach, we provide examples and rough guidelines for translocation programmes concerning the number and origin of individuals for future reintroductions and for the reinforcement of populations with low genetic variability. Finally, we use the Ibex microsatellite data to assess the usefulness of several published statistical tests for detecting population bottlenecks and assigning individuals to their population of origin. This study illustrates that microsatellites allow: M evaluation of alternative translocation scenarios by simulating different numbers and origins of 'migrants'; (ii) identification of bottlenecked. populations (especially using the Wilcoxon signed-ranks test); and (iii) population assignment with a high certainty (P < 0.001) of almost 100% of the individuals (or trophies or carcasses) from two distant populations (especially using STUCTURE or WHICHRUN software).
Garee Khan - One of the best experts on this subject based on the ideXlab platform.
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himalayan Ibex Capra Ibex sibirica habitat suitability and range resource dynamics in the central karakorum national park pakistan
Journal of King Saud University - Science, 2016Co-Authors: Garee Khan, Babar Khan, Faisal M Qamer, Sawaid Abbas, Anwar KhanAbstract:Abstract The study investigates Himalayan Ibex ( Capra Ibex sibirica ) and their range resource condition within the preferred habitat in the Central Karakoram National Park, Pakistan. We apply ecological niche factor analysis (ENFA) using 110 Ibex sighting data and 6 key biophysical variables describing the habitat conditions and produce habitat suitability and maps with GIS and statistical tool (BioMapper). The modeling results of specialization factor shows some limitation for Ibex over the use of slope, elevation, vegetation types and ruggedness. The habitat area selection for the Ibex is adjusted to the Ibex friendly habitat available conditions. The model results predicted suitable habitat for Ibex in certain places, where field observation was never recorded. The range resource dynamics depict a large area that comes under the alpine meadows has the highest seasonal productivity, assessed by remote sensing based fortnightly vegetation condition data of the last 11 years. These meadows are showing browning trend over the years, attributable to grazing practices or climate conditions. At lower elevation, there are limited areas with suitable dry steppes, which may cause stress on Ibex, especially during winter.
Marco Apollonio - One of the best experts on this subject based on the ideXlab platform.
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Forecasting the response to global warming in a heat-sensitive species
Nature Publishing Group, 2019Co-Authors: Francesca Brivio, Stefano Grignolio, Marco Apollonio, Milena Zurmühl, Jost Von Hardenberg, Simone CiutiAbstract:Abstract Avoiding hyperthermia entails considerable metabolic costs for endotherms. Such costs increase in warm conditions, when endotherms may trade food intake for cooler areas to avoid heat stress and maximize their energy balance. The need to reduce heat stress may involve the adoption of tactics affecting space use and foraging behaviour, which are important to understand and predict the effects of climate change and inform conservation. We used resource selection models to examine the behavioural response to heat stress in the Alpine Ibex (Capra Ibex), a cold-adapted endotherm particularly prone to overheating. Ibex avoided heat stress by selecting the space based on the maximum daily temperature rather than moving hourly to ‘surf the heat wave’, which minimised movement costs but prevented optimal foraging. By integrating these findings with new climate forecasts, we predict that rising temperatures will force mountain ungulates to move upward and overcrowd thermal refugia with reduced carrying capacity. Our approach helps in identifying priority areas for the conservation of mountain species
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secondary sexual characters signal fighting ability and determine social rank in alpine Ibex Capra Ibex
Behavioral Ecology and Sociobiology, 2010Co-Authors: Patrick Bergeron, Marco Apollonio, Stefano Grignolio, Bill Shipley, Marco FestabianchetAbstract:Social dominance is a fundamental aspect of male evolutionary ecology in polygynous mammals because it determines access to estrous females. As it is rarely possible to monitor marked individuals of known morphology, little is known about the determinants of male dominance. We studied the social structure of Alpine Ibex males in Gran Paradiso National Park, Italy in 2003, 2006, and 2007. Dominance interactions produced a linear social hierarchy. In Ibex males, body mass and horn length are key traits in male-male combat, and both increase with age. We explored the links between age, body mass, horn length, and social rank. Ibex males showed much age-independent phenotypic heterogeneity and rapidly growing males reached high rank at a younger age than slow-growing males. Because there is no trade-off between horn growth and longevity, fast-growing males may face weak potential costs of rapid growth and high fitness benefit of achieving high rank. Violent interactions were more likely to occur between males similar in both mass and horn length, independently of age. We suggest that only high-quality individuals can afford a strategy of rapid growth for both secondary sexual characters, and likely reap substantial fitness benefits.
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influence of the kid on space use and habitat selection of female alpine Ibex
Journal of Wildlife Management, 2007Co-Authors: Stefano Grignolio, Bruno Bassano, Iva Rossi, Elisa Sara Bertolotto, Marco ApollonioAbstract:Abstract Mammalian females change their behavior during the last stages of pregnancy and during the weaning as a response to new energetic requirements and antipredator behavior. From March 2001 to December 2004, we studied the effects of parturition and weaning on home-range sizes and habitat selection in 28 female Alpine Ibex (Capra Ibex) in a 1,700-ha free area in the Gran Paradiso National Park (Western Italian Alps). We calculated Kernel home range enclosing 95% of each female's locations according to seasonal and bimonthly timescales. Pregnancy did not seem to modify spatial behavior. Lactating females showed smaller home ranges than nonlactating ones after the birth period in June–July. Hot summers slowed kids' growth and prolonged maternal care, modifying mothers' behavior. In summer 2003, which was hotter and drier than usual, weaning females showed even smaller home ranges. Because of their use of antipredator tactics during the weaning season, lactating females showed a higher use of safer habi...
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seasonal variations of spatial behaviour in female alpine Ibex Capra Ibex Ibex in relation to climatic conditions and age
Ethology Ecology & Evolution, 2004Co-Authors: Stefano Grignolio, Bruno Bassano, Iva Rossi, Francesca Parrini, Marco ApollonioAbstract:The spatial behaviour of female Alpine Ibex Capra Ibex Ibex L. 1758, was analysed in Gran Paradiso National Park (Italy). Data were collected on 14 radiocollared females from September 2000 to August 2002, using radio-tracking and direct observations. Seasonal spatial behaviour was influenced by environmental conditions, in particular climatic factors. In the presence of thick snow cover, females significantly reduced winter home range sizes. Snow cover limited Ibex mobility and reduced localization altitudes. Annual home range and winter home range sizes were inversely related to age. Temperature modified the use of space by females during summer. During the hottest summer females moved over larger ranges at higher altitudes. Annual home range sizes (mean 186.2 ha ± 71.7 in 2000 and 182.2 ha ± 70.0 in 2001) and seasonal home range sizes were significantly smaller than those of reintroduced populations, moreover they were smaller that those of males calculated in a close study area in Gran Paradiso Nation...
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spatial behaviour of adult male alpine Ibex Capra Ibex Ibex in the gran paradiso national park italy
Acta Theriologica, 2003Co-Authors: Francesca Parrini, Bruno Bassano, Stefano Grignolio, Siriano Luccarini, Marco ApollonioAbstract:During a two year preliminary study, the spatial organization of a group of male Alpine IbexCapra Ibex Ibex Linnaeus, 1758 was examined in the Gran Paradiso National Park, Western Italian Alps, Italy. From December 1995 to January 1998 we measured annual, seasonal home range and home range during the rut, plus altitudinal migration of 13 radio-collared adult Alpine Ibex. The small annual home range size showed a traditional use of space, confirmed by the high overlapping values between home ranges of consecutive years: the Ibex used the same places from year to year. This was also true during periods of rut. Home ranges closely overlapped in consecutive ruts, while their size changed from winter to winter. Snow cover limited the movements of the Ibex; winter and spring home ranges were smaller than those in summer and autumn. Mean vertical movement patterns were similar in the two years, showing the highest values in summer and the lowest in spring. Space use was never proportional to availability for each altitudinal range.
Achaz Von Hardenberg - One of the best experts on this subject based on the ideXlab platform.
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Climate forcing and density dependence in a mountain ungulate population. Ecology 2004
2020Co-Authors: Andrew R. Jacobson, Achaz Von Hardenberg, Antonello Provenzale, Bruno Bassano, Marco Festa-bianchetAbstract:Abstract. Population models in ecology are rarely validated by comparing their predictions to long-term observations of changes in population size. We have used a variety of analytical tools to examine a 45-year time series of annual censuses of Alpine Ibex (Capra Ibex) in the Gran Paradiso National Park in northwestern Italy. This Ibex population grew from about 3300 to almost 5000 individuals in the 1980s during a decade of anomalously mild winters, and then began to decline in the 1990s. By 1997, the population size had returned to previous levels. Adult survival apparently increased and adult sex ratio may have changed to slightly favor males during the increase in population density. Yearly changes in total population were correlated with seasonal average snow depth and population density over the 39 years for which climate data were available. Our results show that the Ibex population size was limited by both density dependence and deep snow. A model based on these factors fit to the first 19 years of data was used to forecast subsequent changes in total population based on initial population size and yearly snow depth. The model was able to predict the increase and subsequent decline in total population size over the final 20 years of the study but failed to reproduce population levels after the eruption. Our results suggest that the 1980s episode of population growth was primarily driven by increased adult survival, rather than increased recruitment
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don t spit in the soup faecal avoidance in foraging wild alpine Ibex Capra Ibex
Animal Behaviour, 2013Co-Authors: Alice Brambilla, Achaz Von Hardenberg, Bruno Bassano, Ornella Kristo, Giuseppe BoglianiAbstract:Faeces are a major vehicle for transmission of parasites among ungulate hosts. Avoiding feeding in proximity to faeces has been shown to be an antiparasitic strategy in experimental settings with domestic and semidomestic ungulates. However, few studies have tested the faecal avoidance hypothesis in wild herbivores. We tested the faecal avoidance hypothesis in a wild population of Alpine Ibex by comparing the quantity of faeces in grazed and avoided areas. We counted faecal pellets within a plot around a grazing individual and a plot around a spot actively avoided by the same individual. As predicted, grazed plots had lower densities of faecal pellets than avoided plots. Fresh faeces were avoided more often than medium-aged and old faeces. We found consistent differences in the level of faecal avoidance among individuals, but this was not related to the level of gastrointestinal parasite infection or to the age of the host. Our results suggest that wild Alpine Ibex actively avoid foraging near faeces but the antiparasitic value of this behaviour is not evident.
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sex and age structured models for alpine Ibex Capra Ibex Ibex population dynamics
Wildlife Biology, 2012Co-Authors: Andrea Mignatti, Achaz Von Hardenberg, Antonello Provenzale, Renato Casagrandi, Marino GattoAbstract:Past analysis has shown that the population dynamics of Alpine Ibex Capra Ibex Ibex are regulated by both population density and winter snow accumulation. However, recent time series of the Ibex counts in the Gran Paradiso National Park, Italy, show interesting trends in comparison with historical snow data: while the winter snow depth has steadily decreased since the beginning of the 1980s, the Ibex population experienced rapid growth during the 1980s and the early 1990s, followed by a strong decrease. To explain these dynamics, we built novel age-structured population models in which demographic parameters depended on density and snow depth. They included a non-monotonic effect of snow depth and density on the vital rates, the age and sex structure of the population, and spatial segregation between females and males. Using information criteria (AICc, BIC and SRM), we selected the best models and found that: 1) snow and density interacted in determining the demography of all population sex and age classe...
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horn growth but not asymmetry heralds the onset of senescence in male alpine Ibex Capra Ibex
Journal of Zoology, 2004Co-Authors: Achaz Von Hardenberg, Bruno Bassano, Maria Del Pilar Zumel Arranz, Giuseppe BoglianiAbstract:Senescence can be defined as accelerating phenotypic deterioration with old age. For traits that grow throughout life, such as the horns of some ungulates, senescence may be expressed as a decrease in annual growth rates, or an increase in asymmetry, in the years preceding death. Age-specific yearly horn-growth segments of 378 male Alpine Ibex Capra Ibex L. that died from natural causes were analysed in the Gran Paradiso National Park (Italian Alps). Horn annuli displayed fluctuating asymmetry. The hypothesis that asymmetry and size of the annuli of the horns could predict annual survival probability was tested. It was found that between 5 and 11 years of age, male Ibex that grew shorter annuli than the average for the population had a greater probability of mortality over the following years than those with greater rates of horn growth. Horn asymmetry and mortality rates were not significantly correlated. Annulus size, reflecting the onset of senescence, seemed to be a better indicator of individual quality than annulus asymmetry.
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Climate forcing and density dependence in a mountain ungulate population
Ecology, 2004Co-Authors: Andrew R. Jacobson, Achaz Von Hardenberg, Antonello Provenzale, Bruno Bassano, Marco Festa-bianchetAbstract:Population models in ecology are rarely validated by comparing their pre-dictions to long-term observations of changes in population size. We have used a variety of analytical tools to examine a 45-year time series of annual censuses of Alpine Ibex (Capra Ibex) in the Gran Paradiso National Park in northwestern Italy. This Ibex population grew from about 3300 to almost 5000 individuals in the 1980s during a decade of anom-alously mild winters, and then began to decline in the 1990s. By 1997, the population size had returned to previous levels. Adult survival apparently increased and adult sex ratio may have changed to slightly favor males during the increase in population density. Yearly changes in total population were correlated with seasonal average snow depth and population density over the 39 years for which climate data were available. Our results show that the Ibex population size was limited by both density dependence and deep snow. A model based on these factors fit to the first 19 years of data was used to forecast subsequent changes in total population based on initial population size and yearly snow depth. The model was able to predict the increase and subsequent decline in total population size over the final 20 years of the study but failed to reproduce population levels after the eruption. Our results suggest that the 1980s episode of population growth was primarily driven by increased adult survival, rather than increased recruitment.
