La Jolla Cove sits at the center of the San Diego-La Jolla Underwater Park, a 6,000-acre marine protected area established in 1971 and among the first such reserves in California. The cove's granite cliffs shelter a series of seven sea caves carved over millennia by Pacific swells, the largest of which — Sunny Jim Cave — extends 145 feet inland and opens to daylight through a shaft drilled in 1902. The reserve's no-take policy has made the kelp forests here among the densest along the Southern California coast, with stalks reaching 60 feet from the seafloor and harboring over 150 fish species. The leopard shark congregation that arrives each summer between June and December represents one of the most reliable nearshore shark aggregations in North America. Females return to the shallow waters between La Jolla Shores and the Cove to gestate in the warmer sand channels, often visible in groups exceeding 50 individuals. The phenomenon draws marine biologists from Scripps Institution of Oceanography, whose campus borders the reserve two miles north. Water visibility averages 15 to 25 feet year-round, improving to 40 feet in autumn when plankton blooms subside. Kayak and snorkel tour operators launch from La Jolla Shores, a quarter-mile north of the Cove, where the sandy beach provides easier entry than the Cove's rocky shoreline. Outfitters receive permits from the city to guide groups through the reserve and enter five of the seven caves, each named for its acoustic or visual signature — Clam's Cave produces a resonant echo, while Emerald Cave glows green when sunlight refracts through its submerged entrance. The tours concentrate in morning hours when wind remains below 10 knots and marine layer fog clears offshore, typically by 10:00. Afternoon westerlies increase surface chop and reduce underwater visibility as sediment stirs along the kelp line. The reserve prohibits fishing, shell collection, and disturbance of marine life, enforced by lifeguards stationed at the Cove year-round. Violators face citations under California Fish and Game Code. The regulations have allowed Garibaldi populations — the state's official marine fish — to rebound since the 1980s, and their neon-orange bodies now mark nearly every boulder cluster below 20 feet. Sea lions from the nearby colony at Point La Jolla frequently approach snorkelers, particularly juveniles investigating wetsuit fins. The animals are protected under the Marine Mammal Protection Act; touching or pursuing them carries federal penalties.