Alien-like shark caught off Cabo San Lucas identified

By Pete Thomas

A tourist in Cabo San Lucas, Mexico, on Tuesday reeled from the depths a mysterious alien-like fish that looks somewhat like an albino shark.

The peculiar specimen – pinkish-white, with a distended stomach – was caught a mile offshore by a Chicago angler fishing with Capt. Jaime Rendon of the panga, Dr. Pescado. The shark was photographed, then released.

The photos appeared Tuesday night on the Pisces Sportfishing Fleet’s Facebook page, under the heading, “ALIEN FISH IN CABO?”

Tracy Ehrenberg, Pisces general manager, sent the images to biologists in Mexico, hoping for an identification.

We emailed the images to the California’s Monterey Bay Aquarium, and were told that it’s an albino or leucistic swell shark, given its lack of pigmentation.

David A. Ebert, director of the Pacific Shark Research Center Moss Landing Marine Laboratories in Central California, confirmed that it's a swell shark and added that there's only one type of swell shark known to the Eastern Pacific (Cephaloscyllium ventriosum).

"This is clearly a swell shark, no doubt about that, and I am pretty certain it's the species I mentioned," Ebert said.

La Paz-based shark expert Felipe Galván-Magaña ultimately agreed via email that the shark Rendon caught was, in fact, Cephaloscyllium ventriosum.

But it was an odd specimen, with only three gill slits on either side of its head (compared to the 5 to 7 gill slits normally found on sharks), and three rows of very small, nub-like teeth.

Swell sharks, according to the Monterey Bay Aquarium website, expand with water or air when the sharks feel threatened. They're found from southern Mexico to California, and are timid around humans unless provoked.

The catch is somewhat reminiscent of the Sea of Cortez catch, in 2011, of what was widely described as the one-eyed “Cyclops” shark.

That catch was initially thought to be a hoax, but the shark turned out to be a deformed fetus pulled from either a bull or dusky shark hauled up by commercial fishermen near La Paz.

–Photos are courtesy of Pisces Sportfishing