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

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.

Wild boars disturb hair-tube sampling, but adequate replication and inclusion of disturbed tubes retain sampling integrity

“…They were probably attracted by the smell of the bait in the tubes (Lavelle et al 2017), and their rooting activity readily disturbed the tubes. The disturbing effects of wild boar has apparently only been documented for live-traps only (Torre et al 2022a), whereas the present study documented a potential effect of wild boar on ground small mammal sampling when using hair tubes. Therefore, when sampling small ground-based mammals in areas frequented by wild boar, a very effective tube xing system should be used, either using stakes to secure the tubes to the ground or a metal wire to secure the tubes to trees.…”

“…Furthermore, they lack speci city for their target species and they are susceptible to being damaged and potentially rendered ineffective. During sampling with any baited monitoring device, medium to large abundant species may be attracted by the bait and damage the device (Torre et al 2022a). This damage, if substantial, could affect or invalidate sampling.…”

“…The wild boar (Sus scrofa) is a large mammal weighing up to 100 kg with an omnivorous diet (Massei et al 1996), features that make it a problematic species when sampling small mammals by live trapping (Torre et al 2022a). Nevertheless, to our knowledge, disturbance rates on hair tubes by wild boar or other wildlife have not been reported.…”

Wild boar effects on hair‐tube sampling

“…Wild boars were probably attracted by the smell of the bait in the tubes (Lavelle et al 2017), and their rooting activity often disturbed the tubes. The disturbing effects of wild boars have been documented for live-traps only (Torre et al 2022), whereas the present study documented a potential effect of wild boars on small-mammal sampling when using hair tubes. Therefore, when sampling small ground-based mammals in areas frequented by wild boar, a very effective tube fixing system should be used, either using stakes to secure the tubes to the ground or a metal wire to secure the tubes to trees.…”

“…Nevertheless, hair tubes lack specificity for their target species and they are susceptible to being damaged by wildlife and potentially rendered ineffective. During sampling with any baited monitoring device, medium to large species may be attracted by the bait and damage the device (Torre et al 2022). This damage, if substantial, could affect or invalidate sampling.…”