Seafan Grotto
What are the chances of seeing something new off an island you’ve dived hundreds of times? If you’d asked me this before July 19, 2005, I’d have said slim to none. That was before I found the cavern at Seafan Grotto.

I’ve been to Seafan Grotto before. How many times I cannot say, but I do remember seeing the dozens of seafans that grow on a wall there. Yet near the end of my first dive there in July, I found myself at the mouth of a cavern formed by huge boulders. Outside, the water was milky, inside it was clear. From the ceiling of the cavern hung numerous seafans, in colors I’d not seen before. They weren’t red, brown or golden but orange and white.

A solitary garibaldi appeared in my field of view and began making lazy circles in front of me. I swear the fish was sleep-swimming.

Sun streamed down through a large opening in the ceiling of the cavern, about 10 to 12 feet back. Blue water was visible through another, much smaller opening on my left and yet another on my right.

A jiggling motion caught my attention. My exhaled bubbles were hitting the sloping ceiling and rolling upward along it. Some joined others in depressions on the ceiling, forming upside down puddles. I was entranced. I moved toward one of the black puddles, intending to photograph it. Ooops! That was a mistake. My bubbles were knocking stuff off the ceiling, destroying the crystal visibility. I backed out.

After checking my computer for depth so I could find the cavern again, I headed back to the boat. The Truth had deployed two anchors, one in deep water in front of it and one on the boulders that lined the shore. I found the latter anchor a couple of minutes later and swam up the line to make a three-minute safety stop. There, I was surrounded by a school of Pacific sardines. A small yellowtail jetted through the school and the fish scattered.

After a surface interval and a film change (yes, I’m still using Nikonos V cameras underwater), I set out for the cavern once again. I found it easily; it was only a few kicks from the anchor. This time I shot a whole roll of film inside.

Seafan Grotto is in a cove east of Blue Caverns and west of The Quarry on Catalina’s front side. The cavern opening is at a depth of 22 to 25 feet, just west of a small landslide on the surface. The underwater terrain consists of large boulders sloping down to a sandy bottom at about 75 - 80 feet. Kelp grows on the boulders and numerous schools of anchovies hang in the water and swim among the kelp. A wall covered with seafans is just west of the cavern.

Seafans, also called soft corals, are members of the phylum Cnidaria, which includes hydroids, anemones, jellyfish and corals. Their class, Anthozoa, includes anemones, corals and seapens.

I’ve got photographs of five California gorgonians: brown, California golden, red, orange and purple. These invertebrates have stiff but flexible internal skeletons made of a protein called gorgonian. On top of the skeleton there is a soft layer known as the rind. Thousands of retractable coral polyps are embedded in the rind. Each is an individual animal that secretes calcium to form the larger colonial seafan. Since gorgonians are octocorals, the polyp have eight tentacles.

How could I dive a site multiple times without seeing its most intriguing feature? I suspect its because I’m usually deeper than 22 feet. I only happened across the cavern because I was looking for the boat anchor, which I knew was shallow.

It makes me wonder what else I’ve missed over the years.

Bonnie J. Cardone has been diving since 1973. She received the California Scuba Service Award in 1999. For the past six years she has been writing mystery novels and short stories with a diving theme and hoping that some day, somehow, someone will publish them.