Living in Arizona means we have one of the world’s greatest oceans practically in our backyard. The Gulf of California—often referred to as the Sea of Cortez—is a wild, nutrient-rich sea where towering desert mountains plunge directly into deep blue water.
Because the Gulf spans such a massive geographic area, the diving here is incredibly dynamic. What you see off the coast while diving San Carlos in July is totally different from what you will experience in Cabo Pulmo in November or La Paz in February. If you are packing your dive bags and heading south of the border, here is a realistic guide to the animals that make the Gulf of California a world-class destination.
The Welcoming Committee: California Sea Lions
If there is a signature ambassador for the Sea of Cortez, it is the California Sea Lion. There are several massive, permanent colonies scattered throughout the Gulf, making this one of the most reliable (and entertaining) marine life encounters you can have.
Where to find them: Los Islotes (just north of La Paz) and San Pedro Nolasco Island (off the coast of San Carlos) are the most famous spots.
What to expect: While the massive bulls patrol the territory with loud barks, the juveniles and pups are the real stars. They are incredibly curious, zooming around divers, blowing bubbles, and gently tugging on fins. It is like diving in a dog park. Keep your camera ready and mimic their playful energy—they love an engaged audience!
The Filter-Feeding Behemoths: Whale Sharks
Swimming alongside a 30-foot fish that looks like a school bus covered in polka dots is a bucket-list experience for almost every diver. Fortunately, the Gulf is one of the best places on Earth to do it.
Where to find them: The Bay of La Paz and Bahía de los Ángeles (further north in Baja) are the premier hotspots.
What to expect: Whale sharks are highly seasonal, following the rich plankton blooms. In La Paz, the season generally runs from early winter through spring, while Bahía de los Ángeles sees them in the late summer and fall. Because they feed right at the surface, these encounters are strictly snorkeling-only to protect the animals, but the sheer size and grace of these gentle giants will leave you speechless.
Masters of the Blue: Rays and Big Pelagics
The deep waters and strong currents of the Gulf draw in some spectacular pelagic (open ocean) life.
- Mobula Ray Migrations: Twice a year, tens of thousands of Munk’s pygmy devil rays (Mobulas) congregate in the Gulf. They swim in massive, synchronized schools that look like a living underwater eclipse, and they frequently breach, launching themselves feet into the air.
- Giant Mantas: While they used to be common throughout the Gulf, your best bet for seeing Giant Oceanic Manta Rays now is heading down to the Revillagigedo Archipelago (Socorro), or occasionally around La Reina near La Paz.
- Eagle Rays: Spotted Eagle Rays are a common sight along the rocky reefs and sandy drop-offs from Loreto to San Carlos. Watch for them flying in formation along the walls.
The Reef Heavyweights: Morays and Sea Turtles
The rocky volcanic reefs of the Gulf provide endless hiding spots and hunting grounds for the locals.
- Panamic Green Morays: You will be shocked by the sheer size of the moray eels in the Sea of Cortez. Look into almost any large crevice, and you are likely to find a massive, thick green head poking out. They are everywhere, and they are magnificent.
- Sea Turtles: Five of the world’s seven sea turtle species can be found in the Gulf, though Green Turtles and Hawksbills are the ones you will most commonly encounter resting under ledges or munching on sponges.
The Hidden Jewels: Nudibranchs and Blennies
It is easy to get “blue water fever” and spend your whole dive staring out into the ocean hoping for a shark. But if you do, you will miss the vibrant macro life that earned the Gulf its “Aquarium” title.
If you slow down and get close to the rocks, you will find a dizzying array of tiny, neon-colored nudibranchs (sea slugs), like the brilliant purple-and-orange Spanish Shawl. You’ll also find Signal Blennies poking their expressive little faces out of tiny holes in the coral, and if you have an eagle-eyed divemaster, you might even spot a Pacific Seahorse perfectly camouflaged against a gorgonian sea fan.
See It For Yourself
The beauty of the Gulf of California is that no two dives are ever exactly the same. The currents shift, the seasons change, and the ocean always has a surprise waiting.
Want to understand exactly what you are looking at on your next trip south? Join us at 72 Aquatics for the SSI Marine Ecology specialty, then pack your bags and jump on one of our upcoming shop trips to Mexico. The Aquarium of the World is waiting!
