Dealing with stress: responses for a good fitness onAlpine ibex

A disturbance that elicits allostatic individual responses in addition to that imposed by life cycle, is defined as stress. This thesis integrated behaviour and endocrinology (using fecal cortisol and testosterone metabolites) to analyse how Alpine ibex (Capra ibex) deals with environmental pressure. The level of cortisol was directly correlated with maximum temperature in summer, showing the sensitiveness of ibex to thermal stress. I demonstrated that the selective pressures have favoured a definition of the social status in advance respect to the mating season. It remained stable and affected male reproductive success. Testosterone and cortisol are correlated and they jointly reinforced the initial impulse to compete, potentiated pre-existing pattern of aggression, but they have no effects on dominance.I then evaluated the behavioural response of ibex to changes in the landscape of fear. Ibex responded adjusting group behaviour and in particular adult males moved closer to safer areas at the expenses of a suboptimal food intake. I demonstrated, thanks to behavioural and endocrinological data, that the chemical immobilization employed to capture ibex has a reduce impact on ibex biology and it is suitable for conservation projects.The findings of this thesis highlight the preeminent role of the environment in shaping ibex physiology and behaviour. Moreover shown the ability of the specie to efficiently respond and recover both to predictable and to unpredictable disturbance.