Harris, Ellen (2018)
Succession Patterns of Vertebrates in Response to Fire at the Bernard Field Station in Claremont, CA.
Bachelor of Arts, Pomona College, Biology.
Advisors: Nina Karnovsky & Wallace Meyer.
Fires are a critical component of Southern California ecosystems that create disturbance events which may have lasting effects on vertebrates. In this study, I studied the response of vertebrates to two fires (September, 2013 and May, 2017) in California sage scrub habitat at the Bernard Field Station (BFS) in Claremont, CA. Using camera trapping, I monitored species at the BFS starting in June, 2015 and continuing for 29 months. I compared species diversity and richness in unburned and burned habitats using ANOSIM and SIMPER tests, as well as examined species-specific responses and habitat use patterns of frequently captured species. I was unable to differentiate between individuals of a species, so I considered the maximum number of individuals of a species seen in one photo as the total number of individuals of that species seen that day. Cameras captured a total of 45 vertebrate species during the study period. In the first year of sampling for the 2013 fire, species richness in burned and unburned habitats were significantly different. In the second year of sampling, there were no significant differences in either diversity or richness, and in the third year of sampling, there were significant differences in species richness and species diversity. Cameras captured most bird species and woodrat spp. (Neotoma spp.) more frequently at unburned sites than burned sites throughout the entire study period. However, cameras captured mourning doves (Zenaida macroura) more frequently at burned sites than unburned sites. Cameras initially captured desert cottontails (Sylvilagus audubonii) and coyotes (Canis latrans) more frequently at burned sites, then captured them more frequently at unburned sites until the 2017 fire, when cameras again captured them more frequently at burned sites. Other species, including Pacific kangaroo rats (Dipodomys agilis) and California ground squirrels (Otospermosphilius beecheyi), were captured more frequently at 2013 burned sites initially, then transitioned to unburned sites, but then again transitioned back to 2013 burned sites over time. These different habitat-use patterns have important implications for management strategies, as they provide essential information about how different species respond to fire.