Graphical factorial surveys reveal the acceptability of wildlife observation at protected areas.

Approaching large ungulates at protected areas is dangerous both for visitors and the animals. Nudging interventions can mitigate this issue, but conservationists need to be sure about which factors influence the acceptability of human-wildlife encounters, to design them.\n\nIn summer 2018, we recruited a sample of visitors (n = 205) at the Gran Paradiso National Park (Italy). They evaluated the acceptability of 9 digitally modified pictures, depicting a group of visitors observing an alpine ibex (Capra ibex) close to a trail. Pictures were characterized in terms of group size and distance from the ibex.\n\nObserving ibexes was deemed to be acceptable if visitors were further than 25 meters from animals and when groups included less than 3 people. Approaching ibexes at 5 meters was always deemed to be unacceptable. Potential for Conflict Index (PCI) was constant across distance classes and it was generally low.\n\nOur findings indicate that visitors share normative beliefs about the optimal distance and group size, that should characterize encounters with large ungulates, when visiting the park. These normative beliefs are crystallized, because previous encounters with ibexes did not affect the evaluation of each scenario and because the PCI was constant and low. We believe that behavioral interventions aimed at promoting respectful and safe human-ibex interactions can be enforced in areas where this interaction is critical, mostly in form of panels on hiking trails introducing normative pressures on visitors and motivating them to comply with rules.