Wildlife-Crossing Mitigation Effectiveness with Traffic Noise and Light
Connectivity of wildlife populations and communities of interacting species are disrupted by roads and highways. Effective highway crossing structures may mitigate this disruption, assuming wildlife use the structures to cross highways. Wildlife use of structures to cross highways can be highly variable and dependent on structural attributes, human use, and traffic conditions. Studies of animal behavior suggest that artificial light and noise have strong influences on a range of behaviors. This suggests that wildlife aversion to roadways and possibly crossing structures could be related to traffic noise and light. We propose to investigate traffic light and noise as influences on wildlife use of crossing structures intended for wildlife use, or where wildlife use is incidental to the purpose of the structure (e.g., railroad under-crossings). We will use high-resolution sound-pressure and light-level metering combined with camera trap arrays at up to 20 structures across highways in California. Traffic light and noise will be investigated as explanations for variation in individual species use of structures, individual species distance from structures/roadway, and species alpha diversity. We will describe the findings in the context of design of effective mitigation structures for wildlife passage and management of existing structures to improve opportunistic wildlife use.