At low tide the sand at Punta Uvita reassembles into the outline of a whale's fluke, a tombolo roughly 800 metres long that named this stretch of coast long before anyone counted the animals swimming past it. Rangers still call it Cola de Ballena. The shape is accidental, thrown up where opposing currents settle behind a rocky headland. The resemblance is exact. Marino Ballena National Park was declared in 1989, the first marine protected area in Costa Rica. It holds roughly 5,375 hectares of ocean against 110 hectares of land, a ratio that explains why its defining features — Isla Ballena, the rock stacks known as Las Tres Hermanas, the fringing coral and rock reef — are reached by hull rather than by trail. Boats leave from the beach at Playa Uvita, and most private whale watching tour uvita tours work inside the park's marine boundary. The Sistema Nacional de Áreas de Conservación administers the site from Uvita, Puntarenas Province, charging a conservation fee of 6 USD per person, plus tax, that funds ranger patrols, buoy lines and mooring maintenance. Gates operate 07:00–16:00. Two distinct humpback populations pass this coastline. Animals from the northern Pacific, sharing calving grounds with Baja California, arrive in one half of the year; animals from Antarctic feeding waters off Chile arrive in the other. Few coastlines on earth receive both. Mothers use the warm, shallow shelf between Punta Uvita and Isla Ballena as a nursery, where a calf can surface without deep water beneath it. Field researchers have recorded song sequences here that differ measurably between the two groups, and photo-identification catalogues of fluke markings now run to hundreds of individuals. Protection extends well past the park's namesake. Olive ridley and hawksbill turtles nest along the 13 kilometres of beach inside the boundary. Bottlenose and pantropical spotted dolphins work the same bait balls the whales pursue. Frigatebirds and brown boobies hold the offshore rocks, while the reef below shelters parrotfish, moray eels and the occasional whitetip. Bahía Ballena boat charters cross all of it within a few nautical miles of shore, which is why Uvita whale watching excursions so often log several species on one outing rather than a single headline animal. That concentration of marine life, held inside one boundary, is the setting private whale watching tour uvita tickets grant entry to — a protected corridor where a sandbar shaped like a tail marks the edge of a nursery still in use.