Conservation implications of habituation in Nubian ibex in response to ecotourism

Increased fragmentation and easier access to natural areas (e.g. ecotourism) is bringing man in closer contact to wild populations. Such encounters, even when they don't pose a direct threat to wildlife, may induce behavioral changes in animals that in the long run may have negative fitness consequences. We studied changes to the vigilance/group-size effect in Nubian ibex Capra nubiana in response to increased non-threatening anthropogenic disturbance in six sites, subject to different levels of ecotourism. In each site we regressed the average time ibex individuals devoted to vigilance on the size of the group they were with. We then compared the slopes and intercepts of the vigilance/group-size function between the six sites. We complimented these data with a study of how flight initiation distance (FID) changed between the six sites, as an indicator of the level of tolerance that ibex exhibit to increased anthropogenic presence. We found that as anthropogenic presence increased the vigilance/group-size function waned (i.e. the group-size effect was weaker). These findings were associated with reduced FID reflecting increased levels of tolerance, likely as a result of habituation in sites subject to high levels of ecotourism. The loss of the vigilance response as a function of group size may decrease the behavioral diversity in the ibex population. Wildlife habituation to increased non-threatening human activity alters key behavioral attributes that may ultimately impact social structure and other fitness-related characteristics.