Tarantulas are present year-round in Southern California, but their populations tend to increase during the fall months when males search for mates. The most common species in the region is the California ebony tarantula (Aphonopelma eutylenum). Although tarantulas are venomous, they rarely pose a threat to humans. Homeowners can reduce the likelihood of encountering tarantulas by sealing entry points, maintaining proper landscaping, and reducing outdoor clutter.