Using citizen-collected wildlife sightings to predict traffic strike hotspots for threatened species: a case study on the southern cassowary

Assessing the causal factors underpinning the distribution and abundance of wildlife road-induced mortality can be challenging. This is particularly ubiquitous for rare or elusive species, because traffic strikes occur infrequently for these populations and information about localized abundance, distribution, and movements are generally lacking. Here we assessed if citizen-collected sightings data may serve as a low cost and efficient means of gathering long-term animal road-side presence and road crossing information, which could then be used to assess the causative factors and direct mitigation actions aimed at reducing wildlife traffic strike frequency. We explored this principle using two decades of traffic strike records and citizen-collected sightings of the southern cassowary Casuarius casuarius johnsonii. Roads have bisected the cassowaries’ rainforest habitat and despite considerable investment into mitigation strategies for this species, road-induced mortality is considered on...