As the weather warms and the flowers bloom, pollinators including butterflies and moths begin to emerge as well. Look for common species like the California sister butterfly near oak woodlands and mixed coniferous forests, and rare species like the bay checkerspot butterfly, a federally threatened species that lives only in the San Francisco Bay Area (endemic). An easy way to distinguish butterflies from moths is to look for knobs at the ends of their antennae, butterflies have them, while moths do not.