The chamois Rupicapra rupicapra has been termed a highly polygynous species, with a great male competition for mating. If so, a lower survival should be expected for the male sex. From 1986 to 2000, 1801 carcasses of chamois were collected in the Maritime Alps Regional Park, Italy, where a protected, healthy, stable population of chamois occurred (c. 12 individuals 100 ha À1 ). Each year, population structure from carcasses was consistent with that from the count carried out on the preceding year on live individuals. Demographic features (assessed from mortality data, as well as from live counts) showed a balanced age structure and a good adult survival (10% individuals older than 11 years). Mortality peaks showed a cyclic pattern of 3-4 years. Winter severity and local density affected survival, with no significant difference between sexes. The number of carcasses was dependent on the combination of snow depth and mean temperature, in winter. Both sexes showed nearly the same survivorship curves, with a quite similar life expectancy in the first year (males = 6.8 years, females =7.0 years), and the same maximum age at death (16 years), as it may be expected in a monomorphic, monogamous species. This is, however, a rare event among polygynous species, with a high male competition for females and male juvenile dispersion, which normally affect male survival. The similar adult survival of the two sexes could be explained by comparable energetic costs and risks for reproduction, or through greater fat reserves put on by males, before the rut, which may lower their winter mortality.

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A necessary step in the application of animal communication studies to population ecology involves quantitative descriptions of acoustic variation within individuals. Stereotypy is in fact fundamental to allow individual recognition based on call structure and, in turn, to establish the number of different calling individuals in a population (complementing censuses), or to track individuals through years by the acoustic characteristics of their signals (complementing monitoring). Here we centred on the acoustic behaviour of red deer stags during reproduction to analyze its ecological determinants and to test whether calls are individual specific. Scanty information is available on how day time and weather may affect red deer acoustic activity, and whether spectrotemporal analyses of calls could permit to discriminate among different individuals. We centred on roars, the loud repeated calls given by stags throughout the rut, in a mountainous forest habitat, over two rutting seasons. Significant inter-annual differences were found in the duration of the roaring period and in the magnitude of roaring rates. Roaring rate dropped in the wettest days, suggesting that counts by ear may be biased by changeable environmental conditions within and among breeding seasons. By analysing the spectrotemporal features of roars, we found that several spectro-temporal variables varied more among than within individuals. Discriminant analysis classified a posteriori the 72% of the calls to the individuals that uttered them, and the fundamental frequency was the acoustic parameter that best discriminated individuals. Therefore, in areas in which visual information is limited by habitat characteristics, surveys by ear should be performed in dry weather and over several nights to well cover the roaring period. This count method could be complemented by spectrografic analysis of Acoustic activity and stereotypy in red deer 53 stag call bouts to assist in censusing populations and reduce the probability of double counts when stags are moving.

Coexistence of individuals within a social group is possible through the establishment of a hierarchy. Social dominance is achieved through aggressive interactions, and, in wild sheep and goats, it is related mainly to age, body size and weapon size as rank signals. Adult male Himalayan tahr are much larger than females and subadult males. They have a prominent neck ruff, ranging in colour from yellow (5.5-9.5 years old, i.e. young adults, golden males) to brown (7.5-14.5 years old, i.e. older individuals, pale and dark brown males), with golden males being the most dominant. We investigated the social behaviour of male tahr and analysed the relationships between ruff colour, courtship and agonistic behaviour patterns during the rut. Colour classes varied in their use of several behaviour patterns (male dominance: approach, stare, horning vegetation; courtship: low stretch, naso-genital contact, rush). Golden-ruffed males used more threats than darker ones. Pale brown and dark brown males addressed threats significantly more often to males of lower or their own colour classes, respectively, whereas golden ones addressed threats to all colour classes, including their own. The courtship of dominant males was characterised by the assertive rush, whereas that of subordinates did not. Ruff colour of male Himalayan tahr may have evolved as a rank signal, homologous to horn size in wild sheep and goats.