A school of tropical triggerfish dances 20 feet away in 100 feet of visibility. Closer examination of the reef in shallow reveals brightly colored cardinal fish. You are in Mexican waters, to be sure, but getting here did not involve a long plane flight nor even a time-consuming border crossing. In fact, it was only a 90-minute boat ride, straight out of Mission Bay in San Diego, good old USA. No visas, no customs, but a different world just the same.

The Los Coronados are a small group of islands just south of the border. Although close to San Diego, they are just enough offshore to be bathed in very clear water. Coronado del Norte is the northernmost of these islands and the most visited. And probably the most dived site at this island is the Lobster Shack. The small cove is calm, protected, abundant with life. This is not just an easy dive site, it’s fantastic!

Something about the small cove seems to trap or attract small populations of tropical and semi-tropical fishes. This is the northernmost range of the finescale triggerfish. This blue-green disc-shaped fish propels itself casually about the reef, using just undulating rear dorsal and anal fins. Triggerfish are so named because of their unique dorsal fin that resembles the trigger of a gun. The fish will use this bony appendage to lock itself into a reef, making it impossible for a predator to remove. They are a somewhat shy fish, always keeping their distance when approached. Move in slowly and low and sit and wait. Within a few minutes the fish will relax and move in closer. If you move in too fast, they will simply move away or duck into the reef.

The triggerfish like to cruise over a moderately sloping boulder field that varies in depth from 15 to 45 feet deep. Although the boulder field makes up most of the bottom topography in the cove, there is a lot of other variety here. On the north end is a wall that drops sharply from shore to 60 feet or more. This is an excellent area for spotting nudibranchs. Currents are a bit stronger here, so use caution. On the south end the jumble of rock ashore continues outward underwater into a finger reef. Fish are abundant here with opaleyes, garibaldi, and rubberlip perch. Large groups of schooling bait fish move in and out in a ballet of beauty. Isolated boulders can be found out from this reef into as much as 80 feet of water. Between the finger reef and wall, and out from the boulder field is a wonderful sand flat that holds a fun wreck to explore.

A few years ago a large fiberglass cabin cruiser on autopilot at night slammed into the island. Its bottom torn away, the pleasure boat sank quickly into 65 feet of water. Sitting upright, the hulk is fairly easy to find, with much of its superstructure still a gleaming white on the bottom. Follow the rock promitory in the center of the cove straight out. The wreck is located only about 60 feet from the outer edge of the reef. Depending on the viz, you can hover off the sand flat in your search. But with usually very good visibility, the wreck is easy to find. It can often be spotted simply by swimming on the surface.

There is a fair amount of growth on the wreck, but the main attraction here is the fish. Lying close to the reef, fish life is readily exchanged between the two habitats. Garibaldi, blacksmith, and opaleye move in and out. You, too, can move in and out of the wreck easily. It is a small wreck but easy to explore and makes for excellent photography.

California Diving News

So just how did this site get the name “Lobster Shack”? Years ago, Mexican fishermen had a ramshackle shelter ashore. Little remains but the name sticks.

Few lobster remain as well. Some of traps dot the water, but in the reef only a few very small lobster can be found. No gringo hunting here, only Mexican nationals may hunt underwater here. Speafishing can be arranged, but the red tape is so complicated, and the laws change so often, most spearfishers don’t even bother. Nearly all of the dive charter operations out of San Diego have opted to skip on the paperwork nightmare and hunting is prohibited on most boats. Don’t worry, you’re not missing much. Occasionally, yellowtail move through the cove, and calico bass are big and fat, but little else.

In addition to the lobster, also hiding among the rocks are octopus, no doubt in pursuit of the lobster and moray eels, with octopus in mind for dinner. Isn’t the food chain great? It must be a healthy food chain because the moray eels seem to be exceptionally large.

Although you’ll have to look hard to spot the remains of the old fishing shack ashore, the returning elephant seals make their presence a bit more obvious with the barking. Look close among the rocks and you’ll spot the dark charcoal gray females. Males have yet to show up here, and may never, as this is a small rocky beach and male elephant seals take up A LOT of room. There is a permanent rookery on the middle island to the south.

The next time you feel the urge for an exotic dive trip to a foreign land, you need not head for the airport or block out a week. Just head for San Diego and hop on a boat to the Los Coronados for a fun dive that’s different and exciting.

Dive Spot At A Glance
Location
: On the lee side of Coronado del Norte. GPS coordinates N32°26.550′, W117°.773′ (GPS for reference only, do not use for sole source of navigation)
Access: Boat only.
Skill Level: All inside cove.
Depths: 20 to 80 feet, but most diving 60 feet or less.
Visibility: Very good, averaging 50 feet, but often exceeds 70 feet.
Hunting: Prohibited for invertebrates. Spearfishing involves complicated red tape best avoided.
Photography: Good fish photography. Excellent wide-angle with clear water, beautiful fish, wrecks. Shoot macros of moray eels and other fish.
Hazards: Watch currents outside cove.

Shearwater TERN