FALLOW DEER AND WILD BOAR PELLET GROUP DISAPPEARANCE IN A MEDITERRANEAN AREA

Information about local population densities is essential to manage un gulates and is often obtained by pellet group counts. Estimating the r ate of pellet group disappearance is critical for the reliability of t his method. However, no studies have been performed an pellet group di sappearance rates in Mediterranean climate, and no quantitative inform ation is available on loss of pellet groups of wild boar (Sus scrofa) and fallow deer (Dama dama). We investigated disappearance rate of wil d boar and fellow deer pellet groups in a coastal Mediterranean area a nd assessed the influence of possible correlates. Every season, 30 fre sh pellet groups per species were deposited in each of 4 habitat types , and their disappearance rate was recorded the first week after place ment and every 3 weeks thereafter. Pellet group loss varied more in re lation to season than to habitat and followed a similar pattern in bot h ungulates. Pellet groups persisted longest in winter: at least 99% o f fallow deer and 100% of wild boar pellet groups were still present 1 month after deposition, and 78% of pellet groups of both species had remained 3 months after deposition. Conversely. the disappearance rate increased dramatically in autumn, particularly for fallow deer: 88% o f fallow deer and 5% of wild boar pellet groups disappeared 1 month af ter deposition. Dung beetles (Geotrupes: Aphodius) and rooting activit y of wild boar influenced disappearance rate of pellet groups. In Medi terranean regions, pellet group counts should be performed during wint er, and pellet groups should be counted in a 1-month period to optimiz e the reliability of the method.