Quantification of wild-domestic pig interactions
Taking the previous year as a reference, 2/3 of the farmers (20/30) had
observed wild boars in proximity of the farm at a distance ranging
between 1 and 200 m. One third (10/30) had observed evidence of
incursions of wild boars on their farm in the previous year and 90% of
those (8/30) had observed evidence of interactions between wild boars
and their pigs. Those included reports of sexual interactions (reported
by 8/30 farmers), fights (3/30) and trophic interactions (2/30) between
wild and domestic boars. Five farmers reported observing hybrid litters
as a result of sexual interactions between male wild boars and their
respective sows Among those, four farmers kept the piglets for their own
consumption and one brought the sows to the slaughterhouse before giving
birth. Four other farmers declared having observed sexual and or trophic
interactions between two and six years ago, respectively. Incursions of
wild boars in the farm premises were mainly reported in fall (29%),
followed by winter and summer (19 %) while sexual interactions were
mainly reported to occur in summer (6%) and fall (6%). There was a
significant difference between interactions reported in fall (P
<0.05), compared with the other seasons (Fig.4).
Regarding hunters, only one reported direct (trophic) interactions in
the forest. Despite none of them observed direct agonistic interaction,
six of them acknowledged that this kind of contacts could occur. Two
hunters had heard or observed of wild boar incursions in some farms in
the region and two had observed the presence of domestic pigs in hunting
grounds. Eighteen hunters recalled
observing the presence of or hunting hybrids in recent years, mostly
(2/3) between 2013 and 2016. The large majority (10/18) of those reports
referred to animals with a phenotype of pot-bellied pigs.