A Time-Geographic Approach to Wildlife-Road Interactions

Addressing the effects of roadway presence on wildlife movement is a growing concern in both conservation and transportation planning (Corlatti et al. 2009, Fahrig and Rytwinski 2009). One common effect of road presence is the collision between vehicles and animals resulting in direct mortality if an animal attempts to cross the road (Clevenger et al. 2003, Orlowski G and Nowak L 2006). This problem may then be contextualized as an issue of animal mobility including treatment of wildlife movement across roads as a time-geographic problem in GIScience. Developed in the time geography literature, space-time prisms can be used to map potential spatial locations for objects over time given known spatial, temporal, and physical constraints limiting their movements (Hägerstrand 1970, Miller 2005, Winter and Yin, 2010). In research developed by Downs et al. (2013) a voxel based geocomputational approach was used to generate probabilistic space-time prisms, capable of determining the most probable set of entity locations in a space-time trajectory. These prisms can be used to quantify animal locations based on their location probability within a specific space at a given time. This paper extends probabilistic space time prisms to quantify interaction probabilities for wildlife with consideration of roadway influences, at the individual animal level. Specifically, voxel-based probabilistic space-time prisms are used quantify interaction probabilities for moving objects that come in contact with stationary objects.