In the last decade utility solar energy in the U.S. has increased substantially partially to mitigate greenhouse emissions. Solar infrastructure has caused habitat fragmentation across the sensitive desert landscape in southern Arizona, modifying natural vegetation, and influencing animal behavior. Solar facilities use photovoltaic and thermal solar panels that can harm avifauna with their powerful reflective surfaces likely increasing mortality at solar facilities. Bird carcasses found on or near solar facilities are consumed by a variety of scavengers. We were interested in the potential impacts of solar fields on patterns of scavenger behavior. We randomly placed quail carcasses on three solar facility sites and used natural adjacent areas within five kilometers as local reference sites. We placed game cameras to identify and monitor scavenger species, their behavior, and the timing of carcass removal. Monitoring was conducted every three to four days until the carcass was completely removed during a two-month period. We then compared reference sites to solar facility sites to compare scavenging patterns.
Results/Conclusions
The most prevalent scavengers were Coyotes (Canis latrans) and Turkey vultures (Cathartes aura) but species types varied based on geographic location. We found no statistically significant differences in the rates of removal and species richness among reference and solar site locations. There were, however, noticeable trends on removal rates and species richness between sites. We recorded an average of 1.7 scavengers per carcass with a removal rate of 4.95 days on reference sites. Solar sites had an average of 1.2 scavengers per carcass with a removal rate of 7.58 days. Reference sites had higher species richness and average removal rates when compared to solar sites across all three locations. All solar sites were completely fenced off, likely slowing the rate at which scavengers were able to enter and find the quail carcasses. Sites that had more urbanization near the vicinity of solar and reference sites had faster rates of carcass removal and more scavenger diversity than rural sites. Further research may be able to quantify other influential factors such as species distribution, urbanization, seasonality, and variation in solar facility vegetation and infrastructure.