Jacques Cousteau is widely credited with calling the Sea of Cortez “the world’s aquarium,” and anyone who has spent a morning on its water understands why. Writer John Steinbeck was equally captivated: his 1940 voyage through the gulf on a scientific collecting expedition became a book that still introduces many travelers to the region.
The sea is a narrow arm of the Pacific, also called the Gulf of California, and sources estimate it holds more than 900 species of fish and roughly 30 to 35 species of marine mammals. About a tenth of its species are endemic, found nowhere else on Earth.
Where Two Worlds Meet
The secret is geography. The gulf is divided between a temperate zone in the north and a warm-water tropical zone toward the south, down to Cabo San Lucas. In the transition between them, species from both worlds overlap: tropical fish and rays share water with creatures usually associated with the cooler California Pacific. Plankton blooms feed the whole system, drawing blue, humpback, gray and fin whales, along with dolphins and sea lions.
At the far northern end lives the vaquita, the world’s smallest and most endangered marine mammal, a reminder of how precious this ecosystem is.
Experience It From the Cape Side
The Sea of Cortez side of Los Cabos is calm, clear and wonderfully accessible. Stay in Palmilla, Puerto Los Cabos or San José del Cabo and our concierge can arrange a private snorkeling morning, a sunset sail or a whale-watching charter in season.
FAQ
Why is the Sea of Cortez called the world’s aquarium?
Because of its extraordinary marine diversity, a nickname widely credited to Jacques Cousteau.
What lives in the Sea of Cortez?
More than 900 species of fish, dozens of marine mammals, including blue, humpback and fin whales, dolphins and sea lions, and many endemic species.
What is the vaquita?
A small porpoise found only in the northern Sea of Cortez, considered the world’s most endangered marine mammal.
Stay Beside the Aquarium
Choose your base on the Sea of Cortez and let the concierge arrange the water.
