Mast seeding in deciduous forests of the northern Apennines (Italy) and its influence on wild boar population dynamics

Abstract

Pulsed food resources may strongly affect the population dynamics of several consumer species, with consequences on the ecosystem. One of the most common pulsed resources is forest mast seeding. We analysed mast seeding in deciduous forests in a mountainous area of northern Apennines and its effect on population dynamics of wild boar (Sus scrofa L.). We performed a quantitative, 20-year analysis on annual seed production in Turkey oak (Quercus cerris L.), beech (Fagus sylvatica L.) and chestnut (Castanea sativa Mill.) forest stands using litter traps. The wild boar population density was estimated by means of drive censuses and hunting bag records. The role of other biotic (density of predators) and abiotic (climate) factors potentially affecting wild boar mortality was also investigated. Turkey oak and chestnut showed high levels of seed production, whereas lower levels were found in beech. The pulsed resources of chestnut and Turkey oak positively affected piglet density. Analyses also highlighted the influence of snow cover and wolves on wild boar population dynamics. Wild boar can be considered a pulse rate species, the management of which can be improved by annual monitoring of seed production.