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Dive Dry with Dr. Bill

#571: Big Head: The Man of the "House"

You probably thought I was going to publish my fourth and last column in the series on filming the market squid run in our waters with Jean-Michel Cousteau, but I've decided that I should keep you on your toes and inject another topic in this week's paper. Although I like to eat the same thing every morning for breakfast, most sane people like a little variety in their lives... you know, the spice of life! My problem is there is only one breakfast I can "cook..." cold All Bran with orange juice and coffee. It does keep me a pretty "regular" guy though.

The subject of this week's column is related to our squid filming adventure however. Back before Christmas I was scouting squid over in Descanso Bay and as I returned to the dive park, I noticed a bright patch of white on the reef at the boundary. I thought my buddy Catherine was low on air so I kept going, but decided to return to check it out on Christmas Day. The white patch turned out to be a freshly laid batch of eggs guarded by a cabezon which, as my Spanish-speaking friends know, translates into "big headed." I get that way sometimes too.

Now many people tend to refer to ugly fish they observe down under as sculpins. This one, with a face only a mother could love, is actually a true sculpin since it belongs to the fish family Cottidae. The cabezon, known scientifically as Scorpaenichthys marmoratus, was first called that way back in 1822 by the Spanish priest who headed the mission in what is now Ventura. He wrote about it being one of the "excellent fish, either fresh or dried." Keep in mind this was before the refrigerator was invented, although Ben Franklin did some early experiments on lowering temperature by evaporation back when Thomas Jefferson stocked his Monticello ice house with 60 wagon loads of ice each year! The actual invention of the refrigerator was either by Perkins who obtained a patent in 1834, or by Carl von Linde who obtained his German patent in 1877. I was a history major for a while at Harvard so pardon my digression.

Cabezon may reach a maximum length of 39 inches, but the one guarding this nest was just over half that size. The biggest ones may reach 25-30 pounds. They are found from southeastern Alaska down to Punta Abreojos in central Baja California. Unlike most bony fish, cabezon lack scales (something "fishy" about that!). Their coloration varies from brown to red to green with mottling that allows them to blend into the background of the reef. Dr. Milton Love writes that one study found most males were reddish and females greenish but that another study observed no gender-based color linkages.

The color of the fish I observed was indeed reddish, but I knew it was a male regardless of its "plumage." How? Because I'm a marine biologist who researches these columns thoroughly. Therefore, I know that the nests are guarded by the male of the species... just as the male garibaldi and giant kelpfish get stuck with the child rearing duties. Women's liberation in the human species has nothing on these wise female fish.

Spawning by cabezon may occur any time of year, although there tend to be peaks in winter and spring. Females mature at between two and seven years of age. They produce batches of from 50,000 to 150,000 eggs which adhere to the reef. Eggs may be blue-green, white or crimson (go Harvard!) in color. There were two batches in the nest I observed. The larger one was blue-green while the smaller one was very white, but turned bluish green in about 10 days. The male guards the eggs until they hatch, which may take two to seven weeks, averaging about five.

I'm not sure how much guarding the eggs actually need. They are known to be toxic, containing the poison lipostichaerin. In fact, noted West Coast biologist Carl Hubbs and his wife tried some back in the early 1950s and became violently ill. Despite their toxicity, I did notice the cabezon chase away a garibaldi several times during my observation. I'm not sure if our state marine fish had gone to the proper "schools" to learn to stay away from the cabezon eggs. Of course some egg predators must learn from experience so perhaps having papa around to guard the nest is indeed important.

I carefully sampled a single egg from the white batch and observed it under the microscope. One could see the young larva inside with its developing eyes. Later I sampled one of the eggs when it had turned blue-green, and found that the larva inside was just at the hatching stage, still getting nourishment from its attached egg yolk. After hatching and some growth, the young cabezon feed mainly on tiny crustaceans such as amphipods and copepods. When a bit older they start on crabs, lobster, fish, snails, octopus, squid... and even the eggs of other fish. You'd better be careful, Mr. Cabezon... what goes around comes around.

As for human predation, commercial fishermen had a tough sell trying to convince customers to eat a fish that was referred to early on as "repulsive-looking" and "uncouth." The fact that cabezon flesh is blue in color probably didn't help in marketing them either. The blue color comes from a bile pigment known as biliverdin. Its presence in the blood creates the color which also enters the muscle tissue. Of course if I were to serve cabezon to my dinner guests, they would not notice the difference between its flesh and that of kelp bass, yellowtail or white sea bass. That's because I serve all my meals blackened... not in trendy Cajun style though, just thoroughly burned!

© 2014 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 29, 10:00 AM weekdays and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. You can also watch these episodes in iPod format on YouTube through my channel there (drbillbushing). Please help me climb out of self-imposed poverty... buy my DVD's (see this link). Yes, take Dr. Bill home with you... we'll both be glad you did!

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Male cabezon guarding bluish-green eggs and giving me a threat display; cabezon egg and larva with yolk.

This document maintained by Dr. Bill Bushing.
Material and images © 2014 Star Thrower Educational Multimedia