Dive Dry with Dr. Bill: In Winter A Fish’s Fancy Turns To…
By Dr. William Bushing
Now we all know that for many species on this planet, spring is when a young male’s fancy turns toward something other than munching. You know, that other “M” word… mating. After all, munching allows for the survival of the individual while mating helps ensure the survival of the species itself. To avoid being too hemisphere-centric, keep in mind that “down under” (in places like Australia and South Africa, not 60 feet down under) spring occurs September through December.
Hmmm… maybe I should pursue the “Endless Spring” a bit more when I travel. Ah, I’m just a ro-
mantic at heart. However, there are species that are a bit “contrarian” and seek their erotic pleasure at odd times of the year… like winter! Yes, I know, the cold months are great for cuddling and we know where that could lead. But today I’m talking about cold-blooded fish that choose to propagate during the “depth” of a bitter cold SoCal winter. Local species that come to mind include the cabezon (Scorpaenichthys marmoratus) and giant kelpfish (Heterostichus rostratus). Last winter I wrote about the former so this week it is time to focus on the latter. As an aside, I’ve often wondered if giant kelpfish received their common name because they are considered the “giants” of the kelpfish family Clinidae, also referred to as the kelp blennies, or because they like to hang out in the giant kelp (Macrocystis pyrifera) that usually dominates our underwater world.
Giant kelpfish are indeed “giants,” reaching a whopping two feet in length. When our giant kelp forests are healthy, they are often seen suspended upside-down hanging onto the point at which the kelp blade (“leaf”) is attached to the stipe (“stem”). Due to the warm water, low nutrients and storm surge the past six months, giant kelp is not abundant in our waters this winter so they need to find something else to hang on to.
These fish have long thin bodies with a pointed snout and forked tail. At least the “fork” isn’t in their tongue! They may be red, brown, green or yellow in color and the body may be solid, barred, striped or patchy. They can change color fairly quickly to match their surroundings, although females seem to have a wider range of color choices than males. I guess that shouldn’t surprise any Homo sapien who has compared the variety in His and Hers closets (with the exception of “colorful” charac-
ters like myself, of course).. Perhaps due to their more varied choice of body colors, females apparently are observed more frequently amidst green and red algae while the males more often are seen amongst brown algae. Individuals become sexually mature at about 12-18 months when they are just over half a foot in length. Dr. Milton Love states that they will spawn year-round. Most of the observations I’ve made in our waters were during the winter months. Like the garibaldi, the male giant kelpfish establishes the nest site and defends it from other males. Unlike the garibaldi, these fish are not avid gardeners and do not weed out other algae to create their nest. They just utilize larger seaweeds, usually the browns and reds although I’ve observed occasional nests in a bushy green alga (Codium) as well. Due to the total dominance of the invasive Asian seaweed Sargassum horneri this year, native seaweeds are hard to find. The giant kelpfish is one native species that will actually utilize this non-native alga both for shelter and to establish its nests in. Males entice their ladies into the nest by following Chubby Checker’s advice and doing “The Twist.” They gyrate their bodies to attract the girl’s attention and lead her into the seaweed for their love tryst.
The female may lay all her eggs at once while the male watches over her, chases away other males and reenters the nest to fertilize the eggs which adhere to the alga. Dr. Love states that the eggs may be red or brown, but the only color I’ve observed is white. Dr. Love also states that the eggs of a single female are laid in each nest, and it may contain up to 1,200 of them. On several occasions I’ve seen more than one female in a nest laying eggs while the male basks in the glory of passionate polygamy. Hmmm, perhaps those fish were Mormons. I have also observed an interesting behavior by the males. On occasion the male will grasp the female’s tail in his mouth and give it a gentle “love bite” which seems to chase it away. Perhaps in the cold of winter, he just gets a little nippy! However, when I’ve observed male garibaldi do this, it is usually in response to a female that starts munching on the eggs laid by his prior love interest in the nest. Years ago I encountered a nest in which two females were laying their eggs. The male eyed me suspiciously, but finally realized I was no competition or threat.
I revisited that nest several times during the approximately two weeks it took for the eggs to hatch. I think this poor guy was getting really bored with his child rearing duties. He would swim over to me and look into my SCUBA mask. Later, if I held my hand out, he would occasionally swim over to it and rest on
my palm. I think he should have just been glad his responsibilities stretched over a mere two weeks instead of 18 years! © 2015 Dr. Bill Bushing. For the entire archived set of over 600 “Dive Dry” columns, visit my website www.starthrower.org