The Sea of Cortez: Why it’s called “The Aquarium of the World”
The title comes from Jacques Cousteau, who spent a lot of time exploring these waters and was blown away by what he saw. Here’s why it stuck:
The title comes from Jacques Cousteau, who spent a lot of time exploring these waters and was blown away by what he saw. Here’s why it stuck:
Insane biodiversity in a small area
The Sea of Cortez (Gulf of California) packs an absurd amount of life into a relatively narrow body of water:
Around 900 species of fish
More than 30 species of whales and dolphins
Sea lions, whale sharks, manta rays, turtles… the whole greatest-hits album
A huge number of species are endemic, meaning they exist only here.
Cold currents from the Pacific mix with warm tropical water, creating powerful upwellings. That brings nutrients up from the deep, which fuels plankton — and plankton feeds everything else. It’s like the ocean’s version of a five-star buffet.
Many species use the Sea of Cortez to give birth, mate, or grow up. Blue whales calve here. Fish spawn here. Juvenile sea lions and sharks learn the ropes here. It’s not just full of life — it’s where life starts.
Unlike the open ocean, much of the Sea of Cortez is relatively shallow with islands, reefs, and calm bays. That makes marine life easier to see and more concentrated — hence the “aquarium” feel.
Great Barrier Reef (Australia)
Bigger and more coral-focused
Incredible diversity, but spread over a massive area
The Sea of Cortez feels more dense — fewer miles, more encounters
Galápagos Islands
World-famous for unique species and wildlife interactions
Colder, rougher waters
The Sea of Cortez is warmer, calmer, and more accessible for swimming, snorkeling, and boating
Caribbean Sea
Beautiful reefs and clear water
Less large marine life overall
Fewer whale species and less seasonal drama compared to the Sea of Cortez
Red Sea
Stunning coral and visibility
High biodiversity, but limited marine mammal presence
The Sea of Cortez wins when it comes to big animals and seasonal migrations
What really sets the Sea of Cortez apart is the combination:
Tropical and temperate species
Massive animals and tiny reef life
Calm waters and wild seasonal events
You can snorkel with sea lions in the morning, spot dolphins at lunch, and watch whales breach in the afternoon — all in the same place.
Cousteau wasn’t exaggerating. If the ocean had a showroom, the Sea of Cortez would be front and center.
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