Sperm Whales & Advanced Diving at Tortuga

As Isla Tortuga begins to grow large in the horizon, all eyes continue to scan the smooth waters of the Sea of Cortez. Although we are all tired from a four hour crossing from the mainland of Mexico, we have seen many pods of dolphins, jumping sailfish, and even pilot and sperm whales warming themselves at the surface between deep dives.

Often our first sign of whales will be the burst of spray from their blow-holes as they breathe, or the sight of a massive fluke breaking the calm of the water surface.

The south point of Isla Tortuga is a steep and rugged cliff face formed by the lava flows of many eruptions of the nearby volcanoes. The entire Sea of Cortez is a strongly volcanic region, and is itself formed by the slow march of two of Earth's plates diverging.

Below water, the rugged volcanic face continues into a steep wall where scuba divers may encounter any of the treasures of the Sea of Cortez; from the tiny but beautiful Cortez rainbow wrasses, to the majestic arcing wings of manta rays with wingspans exceeding twenty feet. Drawn to the south tip of Tortuga by strong currents, they are much better equipped than humans to handle the conditions here. The south tip is probably the most advanced dive site at Isla Tortuga, and can only be dived when currents are at their most mild.

More photos scuba diving at Isla Tortuga

A den of Panamic green moray eels on the west side of Isla Tortuga
Scuba divers often miss the diminutive denizens such as flatworms (Phylum Platyhelminthes)

Hermaphroditic Rainbow Wrasses

Giant Damselfish at Isla Tortuga

Normally I'm not much of a fan of the damselfishes (pomacentridae). Sometimes pretty, they nonetheless have nasty personalities and I,m quite sure if they grew to the size of sharks, nobody would dare put a toe in the water. I suppose there is a certain amount of respect that these little devils deserve... A ten gram fish that will face off with a wandering diver's hand (and win) isn't short on chutzpah!
There one damsel that I am rather fond of in the Sea of Cortez, the giant damselfish, Microspathodon dorsalis. They are a little more shy than their smaller cousins, but will still charge a diver's mask if the diver recklessly wanders too close to their large nesting territory. They were out in force at Isla Tortuga, and become increasingly common as one moves south along the Baja peninsula.

Scuba Diving at Isla Tortuga

A few more pics from recent trips to Isla Tortuga, a small volcanic island off the coast of Baja on the Sea of Cortez

Stone Scorpionfish

Scissortail Damselfish and Cortez King Angelfish

Closeup of an electric bullseye ray

Scuba Diving at Isla Tortuga

I have been fortunate enough to be able to dive at Isla Tortuga a few times this summer. For those not familiar with Isla Tortuga, it is a small, barren, volcanic island positioned offshore between Santa Rosalia and Mulege on the Baja side of the Sea of Cortez. We crossed from San Carlos aboard the Ocean Spirit. It makes the crossing in about 3.5 hours, although it may take 4.5 grueling hours if the seas are rough.

Getting out of grad school and launching a business has kept me pretty busy these days, but I thought I would at least put up a few pictures from Isla Tortuga while I have the chance.

Stratified layers of lava flows and ash comprise the side of Isla Tortuga



An electric ray settles in for a rest on my fin

A Giant Damselfish protects his clutch of eggs

A pair of Moray Eels keep an eye on me as I pass

More to come soon after I resize additional pics!