‘The human shield effect’: Human-wildlife co-occurrence patterns in the coffee forests of southwestern Ethiopia

Understanding species (co)-occurrence patterns and how these are affected and mediated by humans is essential for the development of management plans to guide coexistence between humans and wildlife. Here, we evaluated two opposing hypotheses regarding the effects of humans on species occurrence: “humans as super-predators” and “humans as shield”, using an existing camera-trap dataset of mammal species occurrence collected in the coffee forests of southwestern of Ethiopia. We applied a multispecies occupancy modelling framework to explicitly examine co-occurrence patterns between humans, top-predators, prey, and crop-raiders, along a gradient of forest integrity (characterized by forest cover and fragmentation). We examined co-occurrence patterns during both coffee and non-coffee harvest seasons. Our results show partial support for the “humans as shield” hypothesis. We found (i) signs of co-occurrence between humans and prey in areas of low forest integrity during both survey seasons, and between humans and raiders during the coffee-season, (ii) signs of co-occurrence between prey and raiders during both seasons, (iii) no signs of negative or positive co-occurrence between humans and top-predators. Our findings indicate that a possible “shield effect” between humans and prey within a predator space, might be undergoing at the edges of coffee forests. Our findings suggest that incorporating humans as one more species in the ecological system can contribute to shed light into the effects of humans on species occurrence and ultimately contribute to inform management for coexistence.