Corridor conservation in southern California under climate change: Understanding mammalian carnivore response to burned landscapes

Background/Question/Methods

Land conservation efforts are challenged by the nature of dynamic ecosystems and shifting climate regimes. In southern California, wildfires are prevalent landscape disturbances expected to become more frequent under climate change. Understanding how changes in this disturbance regime affect wildlife is critical to ensure landscape connectivity. Our study examines patterns of mammalian carnivore occurrence and species richness across an established mosaic of conserved land to evaluate the impacts of shifting fire regimes. We conducted a meta-analysis of remote camera station data from 12 camera trap studies across southern California over a 13-year period. We investigated the occurrence patterns of eight carnivore species in relation to burned and unburned habitats. Using binary logistic regression models, we identified how these species responded to burned landscapes, time since fire, and other environmental variables such as distance to roads and streams that may influence post-fire habitat use. 

Results/Conclusions

Our results suggested that responses to burned habitats are species-specific. Striped skunk and opossum exhibited the strongest response, avoiding burned areas, while other species such as coyote, bobcat, and mountain lion indicated a response to fire only in certain habitat types. We also investigated species richness as a response variable to fire and found a significant negative correlation with time since fire. Logistic regression and occupancy models indicated that variables such as habitat condition, or time since fire were not sufficient to predict species’ response in most mammalian carnivores. However, when coupled with environmental variables such as distance to roads, streams, and developed areas, burned habitats did influence occurrence patterns and species richness. Our results indicated that changes in shrubland composition and structure, predicted under climate change scenarios, may also result in changes in occupancy patterns. We suggest that while fire in large, protected landscapes may not pose a threat to the persistence of mammalian carnivores in southern California shrublands, carnivore populations in corridors and small preserves may be affected by wildfires. To ensure landscape linkages are functional for wide-ranging carnivore species over the long-term, these areas may require conservation planning which recognizes multiple corridor options and fuels management plans.