Dive Dry with Dr. Bill

#250: #250... But Who's Counting?

Thanks to you, my faithful readers, I have reached a milestone. This is the 250th newspaper column in my "Dive Dry with Dr. Bill" series. To celebrate, I will focus on a dive trip I took last week to gather video footage from the waters off La Jolla, California. Why did I travel beyond Catalina's fantastic and highly photogenic submarine gardens? Because my "Dive Dry with Dr. Bill" television series on Catalina Cable will be expanding to the Charter Communications cable network in the Inland Empire and possibly other Charter service areas soon. As the show expands its market, I will be making more such forays into other waters in our region (and across the globe... after I win the lottery) to broaden the show's appeal for my new mainland viewers.

I was apprehensive the night before I left. It had been six months since I had driven my 20-year old Toyota Tercel. I had nightmares of the car not being in the lot when I arrived (who'd steal it?); or if it was, of it not starting. My concerns were unfounded... after all, it IS a Toyota and it started right up as soon as I turned over the engine. I was off to visit three of my favorite dive buddies: Andrea in Mission Viejo, Missy in San Marcos and Heather in Carlsbad. Of course I also visited their significant others (yes, the story of my life). My only diving would be with Missy who would guide me using her local knowledge of the three dive sites we chose in the San Diego area: the South Wall of La Jolla Canyon, Vallecitos Point and the Marine Room.

Missy and I dove the first two sites on Thursday. I last dove this area in May of 2006, with Andrea, and I had heard stories of severe storm damage last winter to the underwater habitats and marine life there. During those previous two dives, I filmed 13 species I'd never recorded on videotape. There was lots of marine life on the shallow sloping sandy bottom then, including several species I'd never seen off Catalina. This time Missy took me back to the South Wall, and there was very little marine life to be seen. I couldn't believe how barren the formerly lively habitats were. Even our shore entry was made difficult by some healthy surf, so maybe the critters were in hiding from the surge.

We did have one "find" here. I had heard that the lion nudibranch (Melibe leonina) was present at La Jolla this year. I don't think I've seen one since the 1970's, and had never videotaped one. Missy found a single individual on an extremely scraggly kelp plant. As you can see from the image below, the footage I got was barely worth saving. However, I've included a well-lit still image of one I filmed back in my Toyon "daze." They really are fascinating shell-less snails, and use the broad circular oral hood to capture plankton and small invertebrates to munch on. When I first saw one in Catalina waters back in 1969, I wrote my Harvard professor, describing my find as a "Hoover vacuum cleaner with wings." He quickly wrote back with the proper identification! That was in the days before I had good access to field guides for California's marine life (or my classmate Al Gore had invented the Internet).

We next dove Vallecitos Point, which Missy said usually had much more life... and again we found relatively little! I did film a solitary California halibut just above the rim of the wall. Unfortunately, I was having trouble with the LCD monitor in my camcorder housing. It just wasn't working, so I had to try to frame the subjects on all three dives using the tiny camera viewfinder. Grrr. Fortunately I think it was just a bad AA battery, but there was no possibility of changing it once underwater... unless I wanted to ruin my new HD camcorder!

Two days later Missy and I dove the Marine Room with her husband Doug and son Mickey. The surf was gentle at this more protected site between La Jolla Shores and La Jolla Cove, and our entry was smooth as a silk nightie. We did the long surface swim out to where the depth dropped below 20 feet and made our descent. As soon as we reached about 70 feet, my dive computer went haywire... flashing its display with great urgency. Missy said it was beeping an audible alarm constantly... but I've been diving so long I couldn't hear it. According to the display, I was dead from oxygen toxicity by the time I reached my maximum depth of 102 feet. Of course I've been diving long enough to know I was still very much alive... and that somehow the computer had re-set itself (without any help from me) to think I was diving a 50% mix of oxygen instead of normal air.

I always dive with a backup computer (my brain... and decades of diving experience), and knew it was safe to continue the dive even if my computer was ready to call a mortician! I'm glad I did, for we encountered a species I'd only seen in field guides years ago, the solitary hydroid (Corymorpha palma). There were actually a few of them on the muddy slope just below the lip of the wall. The one I filmed was about 6" tall. As its scientific name suggests, it looks a little like a dwarf albino palm tree.

When I returned to Catalina, I tried to find a picture of the hydroid to verify its identification. It was not even listed in my primary field guide to California marine life, but I did find it in two older ones from the 1980's. After reading the descriptions there, I knew why it was not included in the other book. The distribution of this species is extremely limited. It is found mainly on mudflats, which have declined substantially in our State due to coastal development, and geographically it is limited to the region from Newport Beach to San Diego.

The solitary hydroid is a relative of the sea jellies (formerly known as Prince... er, I mean jellyfish), sea fans and coral. It has up to 30 slender white tentacles surrounding its mouth located on a tall column or stem that lifts them well above the substrate. For a critter as simple as a hydroid, it has some complex behavior related to feeding. When submerged, they "stand" upright with their tentacles facing down current. They capture food brought to them by the current. Every 3-8 minutes, the polyp will exhibit a bowing behavior in which the tentacles are drawn inward towards the mouth, the stem shortens and the polyp bends down touching the substrate. Reportedly the tentacles then capture food in the form of organic detritus from the mud.

So although I came home with relatively little video to edit, the trip did allow me to encounter one species I haven't seen in decades and one new to me. It also allowed me to purchase a new set of underwater HID video lights from NiteRider with funds from my retirement savings. I will use the lights to produce even more colorful episodes for my expanding cable TV show, and still images for future columns in this paper. Hope you'll all stay with me for another 250 episodes of "Dive Dry with Dr. Bill." With luck and good health, I'll reach column number 1,000 before I retire from diving.

© 2007 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays. Please help me climb out of self-imposed poverty... buy my "Munching and Mating in the Macrocystis," "Great White Sharks of Guadalupe," "Calimari Concupiscence: Mating Squid, " "Playful Pinnipeds: California Sea Lions," "Belize It or Not: Western Caribbean Invertebrates, Fish and Turtles," "Gentle Giants: Giant Sea Bass" or "Common Fish and Invertebrates of the Sea of Cortez" DVD's. Yes, take Dr. Bill home with you... we'll both be glad you did!

Dive buddy Missy and I at Casino Point, the beautiful solitary hydroid; still from the video of the
lion nudibranch (the lighter blob on the kelp) and a much better image of one shot
in my former biology lab aquaria at Toyon Bay.

This document maintained by Dr. Bill Bushing.
Material and images © 2007 Star Thrower Educational Multimedia