Anti Covid-19 face-masks increases vigilance in Nubian ibex (Capra nubiana).

Changes in ecosystems resulting from anthropause caused by Covid-19 relate to both abiotic and biotic factors which have both a positive or negative effect on wildlife. The lockdown was manifested by reduced air and water pollution, lower mortality of animals on the roads, an increase in animals' body condition and reproduction success. On the other hand, the closures lead to an increase in the populations of invasive species or poaching. We studied the behavioural reaction of natural, desert-dwelling Nubian ibex (Capra nubiana) on the appearance of a new element in the environment - the facial-masks. We hypothesized that the mask would trigger a response expressed through differences in the vigilance towards a potentially new threat. We applied the flight initiation distance (FID) technique to check the reaction at the approach of a human with a facial-mask and without it. The average FID was 8.8 m and was longer when the observer was wearing a mask (10.7 m) as compared to trials without the mask (6.9 m). Our study indicates that wildlife, even if habituated to human silhouette at a distance, appear to notice unusual accessories when up-close and respond by increased vigilance and what may affect their overall fitness.