San Diego County is a hotspot of biological diversity, species endangerment, and conservation planning. Mammals, however, have been somewhat underrepresented in San Diego’s innovative conservation plans, partly because of spotty information on the distribution, ecology, and conservation status of our local mammal species. The San Diego County Mammal Atlas is a highly collaborative effort to fill these data gaps. It will serve as a companion to the recently completed San Diego County Bird Atlas and the San Diego County Plant Atlas.
To date we have built a GIS database of over 30,000 mammal-occurrence records for about 100 species from numerous existing information sources and new field surveys.
We reviewed the accuracy and precision of existing location records to ensure their utility for mapping species distributions at a fairly fine resolution (tens or hundreds of meters). We are also testing a variety of techniques for modeling species habitat associations and geographic distributions in the county, using such environmental variables as vegetation, soils, elevation, and climate. Final range maps will depict both known and expected species distributions, and in some cases historic versus current distributions.
Focused field surveys are used to validate predicted distributions and to fill gaps in previous survey efforts.
Other surveys test particular questions of interest to conservation planners and land managers, such as effects of major wildfires on mammal populations and locations of species concentrations, migration routes, or other high-priority conservation areas.
The maps and other information are being collated into a book and CD on the ecology, natural history, behavior, distribution, and conservation and management needs of mammal species in San Diego County. Other chapters describe methods for observing, studying, and monitoring mammal populations, and recommendations for improving conservation and land management efforts for mammals in this remarkable biotic region.