University of California International and Area Studies

The effects of current and future climate change on biological phenology, distribution, community composition, mortality, and extinction have been thoroughly analyzed. However, there has been little analysis of site-specific methods to preserve species and habitats faced with inevitable natural and anthropogenic climate change. The Nature Conservancy (TNC) is currently prioritizing parcels for protection within the Mount Hamilton region. This region contains oak woodlands, riparian habitats and rare and endangered species that are sensitive to the direct and indirect impacts of climate variation. Climate change predictions are based on a low to moderate emissions scenario and a global circulation model downscaled to a 40 kilometer horizontal resolution grid. Binary logistical regression is used to determine which climatic variables influence the distribution of habitat for six high priority species. Climate envelopes based on current and the predicted future climate are compared to determine the amount habitat lost due to climate change. Blue oak (Quercus douglasii) woodlands are the least impacted, but are still projected to lose up to 55% of their habitat. Bay Checkerspot Butterflies (Euphydryas editha bayensis) are the most impacted, and are projected to lose 100% of their habitat. Migration to areas of new habitat is restricted by elevation, low dispersal rates, and the lack of suitable habitat conditions. TNC and other organizations can help to avoid local extirpation of high priority species by preserving high elevation future habitat, migration corridors, and transplanting species upslope. With these efforts, the Mount Hamilton region could continue to support its rich biodiversity despite a rapidly changing climate.