The highlights of the southern Sea of Cortez are:

Los Islotes :  Los Islotes, a small island at the northern end of Isla Espiritu Santo, is home to one of the largest sea lion colonies you're likely to encounter anywhere.  You'll hear them before you see them.  Their barking can be nearly deafening !  Then, you'll spy them  ... some frolicking in the water and some catching rays on the rocks. 

They are there in the hundreds.  Once in the water, you'll probably be approached immediately by some of the pups, as they tend to be the most curious and playful.  The mothers watch over them carefully, however, so follow the instructions of your guides carefully.  But, expect to be surrounded by loads of animals, many of whom will come right up to you to check you out, just as you are checking them out. 

Undeniably, it’s the sea lions which are the highlight here. The babies are adorable, the young from last year are energetic & playful (they’ll try to snack on your fins & snorkel) and the adults are superbly graceful as they perform their underwater ballet.

But, more than just the fabulous & entertaining colony of sea lions, Los Islotes is also a place where you may be able to observe passing mobula rays, sharks and large schools of pelagic fish, such as Mexican barracuda. Underwater photographers will find some worthwhile macro life here and dense shoals of schools of sardines. Everyone delights in the striking blue & gold king angelfish and the flashy, bright-yellow surgeonfish.

El Bajo :  El Bajo is known for hammerhead sharks, whale sharks and marlin. There are three seamounts, one of which in particular, attracts schooling hammerheads (sometimes very large groups) which can be seen on most dives here. In addition, you’ll find yourself in a “surround-sound” of jacks and may be lucky enough to observe manta rays, whale sharks and a variety of other shark species gliding past.

While the hammerheads are the main draw, no less impressive are the giant, circling clouds of fish (jacks, wahoo, tuna) and a huge colony of green moray eels. Also, the variety of corals here means reef fish are also lurking: scorpionfish puffer fish, creole fish, hawk fish, snappers, and grunts.

El Bajo is a pretty strong drift dive and not recommended for novice divers.

Swanne Reef (also known as Swannee Reef) :  Mexican goatfish, spottail grunts & damselfish abound in this outlying reef where you find coral heads & gorgonian-covered walls. Also, there are more macro photo ops here with the omnipresent & adorable blennies. Larger sea life includes jacks and barracudas as well as MORE of those spirited sea lions and often a few dolphins.

Salvatierra Wreck : Swanne reef was an unexpected element in the water for a ferry captain and, as a result, a 262-foot ferry lying at about 65 feet of depth. It has become an artificial reef and popular dive. Loads of grunts and angel fish make their home here amongst the corals and fans which have taken hold over nearly 40 years. The ferry was carrying a cargo of trucks which are still visible and make interesting pictures. No penetration is allowed on the wreck.

La Paz Bay :  Your itinerary may include a visit to swim with the whale sharks near La Paz.  Typically from November to April is when you find the largest concentration of these alluring animals, although a few hang around all year. In spite of their immense size, they are harmless filter-feeders rather than predators and present no danger to humans snorkeling with them. Their gentle nature makes them great photography subjects but even more, just an incredible being to pass a bit of time with. 

Cabo Pulmo :  Cabo Pulmo was declared a National Marine Park in 1995 and its marine life has been recovering & beginning to flourish ever since (after years of over-fishing and poor conservation practices).  It has been a no-fishing zone since 2000. There’s an extremely rich reef here where loads of fish and critters breed, so the food supply is ample for the sharks (and other passing pelagics) and the underwater photography is terrific for divers. You can expect to see some, or most of the following:  mobula rays, eagle rays, dolphins, marlin, groupers, snappers, several sea turtle species, sharks (bull sharks … plus the occasional mako, lemon or silky). 

You’ll also find the typical Sea of Cortez whirling schools of jack fish at Cabo Pulmo plus pork fish, snappers, surgeonfish and groupers. And, indications are that the mantas are returning here. They had disappeared for some years, but there have been significant sightings more recently.

From September to December, when the water is crystal clear, brash & brawny bull sharks are commonly seen at Cabo Pulmo. They seem particularly attracted to the “El Vencedor” wreck site but they are seen a various other sites in the immediate vicinity also. As there are not a lot of destinations in the world where you can swim with the bull sharks, this is a special treat in the Sea of Cortez.

Deep South :  The largest known ray aggregation on earth (literally thousands of mobula rays) happens in this sea between May & July.   A bit like the sardine run (and other natural phenomena) there area no guarantees that the show will go on.  But, luck has held out the past few years.  Divers during this time have the opportunity to snorkel and freedive with mobula rays and predatory pods of orcas, as well as huge pods of dolphins and even possibly sperm & fin whales and massive pregnant whale sharks out in the deep ‘desert’ ocean. Mobula rays often like to breach the surface, so there will be ample opportunity to witness these gravity-defying acrobatics out of the water. This is an idealt trip for both divers and snorkelers.

The highlights of the Midriffs are:

Isla Angel De La Guarda : If you like the little stuff, you’ll enjoy diving “the Guardian Angel”.  In some ways it’s like a muck dive but in sand. The BIG jawfish are perhaps the most remarkable of the critters … but the blennies are great too, particularly when the guys are “courting” the girls and flaunting their amazing colors!  Plenty of gobies and multiple species of nudibranchs, colorful flatworms, shrimp, scorpionfish, even sea horses. Of course, you'll find eels & octopus plus good-sized schools of fish …. triggerfish, snappers and groupers.  Expect lots of turtles, plenty of sting rays flitting around, and what everyone most wants to see … those groups of high-spirited sea lions. Usually, you’ll be treated to some cavorting dolphins and if you’re lucky, perhaps even mobula rays and / or pilot whales.  Coral lovers can swim through an impressive jungle of black corals.

San Pedro Martir – sea lion heaven : This is one of those sites where you hear the animals before you see them. Loads of sea lions will be barking a welcome to new visitors and tuning up their underwater performances. They race around, then often come directly up to your mask or try to have a munch on your snorkel. You’ll also find a lovely wall with corals, scorpionfish, nudibranchs & pufferfish …. and more black coral. Topside, the excitement is all about bird life. San Pedro Martir is a breeding ground for large colonies of brown-footed and blue-footed boobies.

Salsipuedes & Las Animas : More macro delights here, the giant jawfish being perhaps the most intriguing. But, there are big sea fans harboring long-nose hawkfish. There are countless nudibranchs, stingrays darting around, plenty of turtles and lots of trevallies.

Bahia De Los Angeles : Plenty of good diving here at the various islands in this bay where you’ll find large angelfish, an assortment of other reef fish, spiny urchins, starfish, soft coral & large green morays. But, most people come to Bahia Los Angeles, between July and November, to swim with the whale sharks. On days when the water is calm (as it usually is during these months) you should have gentle interaction with the animals. Fortunately, there are few boats and snorkelers often find themselves along with the world’s biggest fish. The more relaxed amongst the whale sharks, will let you hang with them for quite a surprising amount of time as they glide and feed, either watching you or oblivious to you. It’s a scintillating experience.

Immense sardine & mackerel bait balls form off the coast of Baja, in the cold currents, and the predators know when and where they’ll be.  Speedy marlins zip through the water like lightning strikes, spearing their prey with their swords then going back for more.  Sea lions join in, rather like sheep dogs herding sheep.  The feeding frenzy which ensues is wild and spectacular to observe !

Striped marlins are some of the fastest and most agile fish in the ocean.  They attain speeds up to 80 kilometers per hour / 50 miles per hour.  Sadly, they are prized trophy fish and sport fishing has been the major “industry” to hold court in the waters off Mexico until recently. However, there is a new eco-tourism effort growing in Magdalena Bay and by making a trip there, divers can help the locals to believe in the concept that the marlins are worth more alive than hanging on someone’s wall.

The superb Nautilus Under Sea has just announced 7-night trips from Cabo San Lucas, at the tip of the Baja Peninsula, to Magdalena May in October.  You can find spaces and book online here.

There are also land trips which leave Cabo, heading through a starkly beautiful landscape to a small town on the bay where you can spend the night and start fresh in the morning, making your way in the launch to where you see large aggregations of sea birds circling.  It’s nearly 100% certain that there are bait balls just below the surface …. and marlins.

You slip into the water and the fun begins.

There can be hundreds of fast-moving bait falls with up to 20 or 30 marlins in rapid pursuit.  Joining the excitement are sea lions that find the sardines & mackerel just as tasty and are also expert hunters. Most of the time, the marlins and sea lions seem to work in a coordinated effort to herd and to split the bait balls to more easily capture the prey. Of course, the sea birds are constantly dropping in from above to get their fair share and sometimes you'll see tuna joining the action from below. It’s exotic marine madness.