Enhancing ecological connectivity and safe passage for wildlife on highways between the southern Santa Cruz Mountains, Gabilan Range, and Diablo Range in California (2018-2022).
From 2018-2020, Pathways for Wildlife conducted the Enhancing Ecological Connectivity and Safe Passage for Wildlife on Highways between the Southern Santa Cruz Mountains, Gabilan Range, and Diablo Range in California study. This study was completed through a partnership between Peninsula Open Space Trust (POST), Pathways for Wildlife, Tony Clevenger, Caltrans, and SCL Ecological.
The study assessed connectivity between the southern Santa Cruz Mountains, Gabilan Range, and Diablo Range in California, which is a regionally important area for wildlife movement. We used wildlife cameras to monitor existing highways under crossings at 42 sites, conducted roadkill surveys along five highways, and completed habitat suitability and cost surface modeling for a suite of terrestrial mammal focal species.
We used the results to identify 19 Connectivity Emphasis Sites with the most opportunities for reducing wildlife–vehicle collisions and improving connectivity for all wildlife, including fragmentation-sensitive species such as mountain lions and American badgers.
Our final report includes site-specific recommendations as well as crossing infrastructure information sheets to help guide agency implementation of proposed improvements (Figure 3). The results and recommendations from the study were used by Caltrans District 5 to program a Project Initiation Document currently underway, which includes preliminary engineering plans for a wildlife overpass on U.S. Highway 101 at one of the highest priority, critically urgent sites.
