WILD RED DEER (CERVUS ELAPHUS, LINNAEUS, 1758) POPULATIONS STATUS ASSESSMENT: NOVEL METHODS USING HAIR

The assessment of free-ranging wild red deer (Cervus elaphus) populations status is an important tool in wildlife management, because of, in some areas, this species reaches high densities, which can increase the occurrence of road accidents, of damages to agriculture and forest regeneration, and, not last, can reduce the fitness of the species itself. In fact, high density populations compared to low density ones usually show lower levels of fertility, higher prevalence of disease, higher mortality, worst general body conditions and nutritional status. Nevertheless, collecting samples to assess free-ranging populations status is often difficult. Hair is a safe, readily available, and easy to store and transport matrix, and hair sampling does not involve pain or infection risk for the animals. Furthermore, hair assay provides a long-term endocrine profile. Thus, this matrix could be useful to assess long term cortisol accumulation and other hormonal substrates of social trends. Furthermore, hair can be an important indicator of accumulation of environmental pollutants in ecological, clinical and hygienic studies. In this thesis three studies were carried out, concerning respectively the extraction of cortisol, progesterone (P4) and arsenic from hair. We show how the analysis of hormones or other substances in hair constitutes a highly promising and reliable method for assessment of substances secretion over extended periods of time in free-ranging red deer. In particular, our findings suggest that i) hair cortisol concentration provides a good index of long-term HPA axis activity and allostatic load; ii) hair progesterone concentration, in combination with other sexual hormones concentrations in hair and biometric measures, may contribute in the future to develop a reliable and easy pregnancy test for free-ranging red deer; iii) hair arsenic concentration could be analysed, not only in order to assess wild populations status, but also to control wild animals contamination, in biomonitoring investigations or in health programs. In conclusion, the assessment of hormones and micro-elements in the hair seems to be an interesting tool for future wild species management.