Small mammal sampling incidents related to wild boar (Sus scrofa) in natural peri–urban areas

I Torre,A Raspall,J Grajera,M Vilella,S Cahill

doi:10.32800/abc.2022.45.0033

Abstract

The wild boar (Sus scrofa) has recently shown continuous population increases in many countries, leading to a rise in conflicts with human activities, including habituation to people and urban areas. Wild boar can disrupt the sampling of small mammals by reducing the number of potential captures. In this study we analysed whether sampling incidents recorded within a small mammal monitoring programme (SEMICE, www.semice.org) might be related to the density of wild boar in a network of protected parks. Our results suggested a peri–urban effect that was independent of wild boar densities in the protected parks; the number of damaged traps increased (rendering them inoperable for captures) and potentially resulted in underestimates of small mammals due to fewer functioning traps in the study area. We hypothesised that this high rate of damage to traps in a small and localised area in a peri–urban park could be related to wild boar associating human presence with greater opportunities to obtain food items of anthropogenic origin.

Highlights

Wild boar (Sus scrofa) populations are currently expanding both in distributional range and number in many countries (Keuling et al, 2017; Massei et al, 2015)
The generalized linear mixed models (GLMM) analysis confirmed that incidents caused by wild boar were mostly associated with the selected predictors (62 % of deviance), being higher in Collserola than in the other parks sampled in the province of Barcelona: the probability of incidence was twenty
We showed that the behaviour of wild boar, and the sampling incidents they caused, could affect our live–trapping estimates of the population size of small mammal communities by reducing the number of traps available to capture animals during field sampling

Summary

Introduction

Wild boar (Sus scrofa) populations are currently expanding both in distributional range and number in many countries (Keuling et al, 2017; Massei et al, 2015). Traditional recreational hunting is declining and is insufficient to restrain the population growth of wild boar (Massei et al, 2015). Wild boar can display compensatory population responses when hunting pressure is high (Gamelon et al, 2011; Servanty et al, 2011). Synurbization of wild boar is a recent phenomenon. Their presence is increasing in ever–expanding [peri] urban environments where they can often thrive on a combination of both natural and anthropogenic food sources, and may become habituated to the presence of people (Cahill et al, 2012; Putman et al, 2014; Náhlik et al, 2017; González–Crespo, 2021)

Methods

Results

Conclusion