Longcore, T., L. Almaleh, B. Chetty, K. Francis, R. Freidin, C.-S. Huang, B Pickett, D. Schreck, B. Scruggs, E. Shulman, A. Swauger, A. Tashnek, M. Wright, and E. E. Boydston. 2018. Wildlife corridor use and environmental impact assessment: a southern California case study. Cities and the Environment11(1):art4.
Environmental planners often rely on transportation structures (i.e., underpasses, bridges) to provide connectivity for animals across developed landscapes. Environmental assessments of predicted environmental impacts from proposed developments often rely on literature reviews or other indirect measures to establish the importance of wildlife crossings. Literature-based evaluations of wildlife crossings may not be accurate, and result in under-estimation of impacts or establishment of inappropriate mitigation measures. To investigate the adequacy of literature-based evaluations, we monitored wildlife use of a freeway underpass that had been identified as critically important to wildlife connectivity, and which was evaluated in an environmental review document. Photographs were obtained from a network of trail cameras over 3 years. Six mid- to large-sized native mammal species used the underpass and two other mammal species were photographed near the underpass but not using it. American badger (Taxidea taxus) was photographed at a higher rate in the underpass than in the surrounding area. Gray fox (Urocyon cinereoargenteus) was rarely detected in the underpass relative to surrounding habitats, whereas the absence of mule deer (Odocoileus hemionus) in the underpass was unexpected, given relatively frequent detection in adjacent habitats. These results differed from the environmental assessment in that American badger was listed as “potentially” present while mule deer were expected to use the underpass. Results underscore importance of gathering data to document wildlife use of corridors, because some species do not or rarely take advantage of apparently suitable corridors, while others may be present when assumed to be absent.
We participated in force in the 20th University of Southern California Undergraduate Symposium for Scholarly and Creative Work. Our contributions included:
- Classification System for National Park Sites Based on Nightscape Lighting Profiles (Harrison Knapp and Benjamin Banet)
- Spatiotemporal Analysis of Lighted Boats at Night (Eliza Gutierrez-Dewar)
- A Photographic Light Pollution Assessment Across Western Public Lands (Benjamin Banet)
Characterization of Spatial and Spectral Distribution of Outdoor Lighting at Wrigley Marine Science Center (Camille Verendia, Lisa Cortright, and Jasper McEvoy)
Amanda Gilmore, who worked this semester on habitat modeling for invasive lionfish, presented her ongoing work with our colleague Dr. An-Min Wu.
Awards were won. Eliza took the 2nd Place award in physical sciences for her work analyzing squid boat lights off the coast of California, while Ben won Honorable Mention for his field work documenting light pollution on public lands across much of the American West with hemispherical photography.
Acknowledgments are in order. Funding from the Undergraduate Research Associates Program, Summer Undergraduate Research Fellowship, and Student Opportunities for Undergraduate Research (all at USC) made this work possible. We also had funding from the National Park Service via the Southern California Research Learning Center for part of Ben’s work (the part in the Santa Monica Mountains National Recreation Area and Channel Islands National Park). Eliza’s work was made possible by collaboration with Chris Elvidge at NOAA, who provided the outputs of their boat detection algorithm. The Wrigley Institute and Wrigley Marine Science Center supported the lighting assessment there with travel, room, and board. Photos from the symposium and awards dinner are by Susan Kamei; I was at the AAG annual meeting.
Reporter Stephanie Pain contributed an excellent summary of recent research on light pollution, “There Goes the Night,” with interviews and summaries of research from around the world. Knowable Magazine is the partner publication to the Annual Reviews series, which recently published a review from the Gaston lab, Impacts of Artificial Light at Night on Biological Timings. Our favorite part, however, is that the article included an image from Ben Banet, who graduates this spring with an interdisciplinary B.S. in conservation and GIS that focused on light pollution. His image of the Smithsonian research hut on Mt. Whitney with the glow of Los Angeles on the horizon 285 km in the distance provided a striking illustration for the article.
Yu Chuan Shan, Ben Banet, and I have been working the past couple of years on developing a monthly database of upward radiance from within and buffers around all of the National Park units in the United States. They are presenting the research today at the USC undergraduate research symposium. The results presented only scratch the surface of what we can do to analyze this high-resolution database over space and time.
Shan also put together a website to walk through the project.
The poster can be downloaded here. Please cite as:
Shan, Yu Chuan, Ben Banet, and Travis Longcore. 2017. Spatial and Temporal Analysis of Nighttime Lighting In and Around National Parks. USC Undergraduate Symposium for Scholarly and Creative Work (Los Angeles, April 12, 2017).