UC Davis Institute of Transportation Studies

This project included estimation of animal occurrence near and using structures (e.g., culverts, street, and RR crossing structures) to cross the Interstate-80 right-of-way in the Sierra Nevada, California. A combination of track plates near over-crossings and remote cameras at under-crossings was used to index wildlife occurrence and crossings. Diversity was relatively low in the highway right-of-way and at highway under-crossings. Across six highway under-crossings, only eight of 38 possible species were observed moving through these crossings from one side of the highway right-of-way to the other. Alpha diversity at highway crossings ranged widely for wildlife near street under and over-crossings, but was not related to nearby land development. Wildlife use of existing under-crossing structures was inversely proportional to the presence of humans and frequency of human use of the same structures. This has important implications for effectiveness of existing structures and purpose-built “wildlife crossings” to provide for wildlife movement.