When: Throughout February.
Where: Año Nuevo State Reserve, Pescadero, CA.
What: More than 3,000 seals come to Año Nuevo each winter to battle for mates, breed, and give birth at the northern elephant seals' largest mainland breeding colony.
Tip: Docents will lead you up to 50 feet from the seals, but you'll need a reservation for the guided walk. Call the reservation hotline at 800-444-4445 (they recommend at least a month in advance).
For info: www.parks.ca.gov; 650-879-2025.