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Dive Dry with Dr. Bill

#251: The Island Kelpfish

I was an off-island kelp forest ecologist this past weekend and didn't do a single dive. Due to unexpected circumstances, I found myself taking my wonderful niece Kara to watch the USC-Washington State football game Saturday. A rain cloud hung over the Coliseum during much of the game, so at least I did get wet. As expected, the Trojans made mince meat of the Cougars (who I have a real fondness for... after all, my favorite team is whoever is playing USC, and cougars are my favorite type of woman). My niece was pleased as she hopes to attend USC in two years. Just wish I could have taken her to see my alma mater play Yale in the fall of 1968. Both teams were undefeated and untied in the race for the Ivy League championship. Harvard was losing 29-13 with 43 seconds to play. However, that was in the days when football was a game rather than big business, and anything could happen. When the final second ticked off the clock, our team was victorious 29-29 after scoring 16 points in less than a minute. But I digress... I'm here to talk about marine life rather than football.

There are several different species commonly referred to as kelpfish in our waters. They range from the giant kelpfish measuring up to 24" to the much smaller island kelpfish which may reach a full 4" in length... if it lives long enough. These kelpfish species belong to several different genera, but all are members of the kelpfish and fringehead family, which also includes (as you might have guessed) the sarcastic fringehead and one of my favorites, the orangethroat pikeblenny. This week I'm going to focus on the smallest member of the group, the island kelpfish, which I encounter frequently on rocky reefs in our waters.

Imagine my surprise when I turned to Dr. Milton Love's usually comprehensive book Probably More Than You Want to Know About the Fishes of the Pacific Coast and discovered this species wasn't even included in it. I wondered how Milton, a Cousteau associate from the mid 70's, chose the fish species he included in his book. He wrote "my goal was to cover those species which you are most likely to see when diving, fishing or hiding in dumpsters behind fish markets." Now that may explain the absence of the island kelpfish. At 4" long, its tiny mouth is not likely to be caught on most fish hooks, and a filet of this fish would be much too tiny to be sold in any reputable fish house like Armstrong's. By the way, I think it would be pretty cool to have Milton's name, Dr. Love! For now I'll have to be satisfied with "Dr. Bill."

The island kelpfish (or trambollo isleño for my Spanish speaking readers) is a southern species, known from San Miguel and Santa Cruz Islands to Point San Pablo on the Baja California peninsula. It may be observed around rocky reefs to a depth in excess of 160 feet. The only other kelpfish that resembles it closely enough to cause confusion is the deepwater kelpfish. As its name suggests, it is found in deeper water from about 75 to 300 feet. If I saw a kelpfish at that maximum depth, I'm sure nitrogen narcosis would cause me to be very confused about its identity... not to mention that I'd probably be dead from oxygen toxicity unless I was diving a special technical mix of gasses.

This fish is a bottom dweller, often resting on a rock surveying its domain. It is probably on the lookout for munchables, mostly small crustaceans like gammarid or caprellid amphipods and shrimps. They seem to function as miniature ambush predators, waiting for the crustacean to come within striking distance. They then dart out to grab the unsuspecting prey. To complete the food web in the mutual eating society, these fish are eaten by a variety of larger fishes. Several years ago I was surprised to discover that these tiny fish are one of the primary cleaners of the giant or black sea bass off Anacapa Island, picking parasites off their bodies at designated "cleaning stations." In our waters it is usually the larger señorita and sheephead, both wrasses, that I see performing this function.

The island kelpfish's scientific name, Alloclinus holderi, may ring some bells for residents of Catalina or the Pasadena area. It was originally named Starksia holderi by Lauderbeck in 1907, in honor of Charles Frederick Holder. Holder was not only a scientist and fisherman on our island in the late 1800's and early 1900's, but also co-founder of the Tuna Club and the Rose Parade. The specimen from which this fish was scientifically described came from our waters.

At times I wish I were living a century ago to make these early discoveries of the new marine critters here off Catalina. Then I would have had a number of species named after me. Some would say SCUBA gear was not invented then, and had to await Cousteau and Gagne's invention in 1943. However, others place the invention of SCUBA much earlier. A French dentist, Lemaire D'Augerville, patented and used a successful design in 1828. If his device had not been so far ahead of its time, I could have been diving here way before SCUBA Luv or Catalina Divers Supply appeared. Hmmm, but where would I have filled my tank for the next dive?

© 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!


Several island kelpfish posing for the camera.

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