Diet Overlap and Foraging Activity between Feral Pigs and Native Peccaries in the Pantanal.

Inter-specific competition is considered one of the main selective pressures affecting species distribution and coexistence. Different species vary in the way they foragein order to minimize encounters with their competitors and with their predators. However, it is still poorly known whether and how native species change their foragingbehavior in the presence of exotic species, particularly in South America. Here we compare diet overlap of fruits and foragingactivity period of two sympatric native ungulates(the white-lipped peccary, Tayassu pecari, and the collaredpeccary, Pecaritajacu) with the invasive feral pig(Sus scrofa) in the Brazilian Pantanal. We found high diet overlap between white-lipped peccariesand feral pigs, but low overlap between collaredpeccaries and feral pigs. Furthermore, we found that feral pigsmay influence the foragingperiod of both native peccaries, but in different ways. In the absence of feral pigs, collaredpeccary activity peaks in the early evening, possibly allowing them to avoid white-lipped peccaryactivity peaks, which occur in the morning. In the presence of feral pigs, collaredpeccaries foragemostly in early morning, while white-lipped peccaries foragethroughout the day. Our results indicate that collaredpeccaries may avoid foragingat the same time as white-lipped peccaries. However, they forageduring the same periods as feral pigs, with whom they have lower diet overlap. Our study highlights how an exotic species may alter interactions between native species by interfering in their foragingperiods.