Throughout my early career as a biologist I focused on marine algae and invertebrates, those critters without a backbone. After all, someone had to look out for the "little guy." When I did my Ph.D. research, one of the professors on my doctoral committee was the noted ichthyologist Dr. Al Ebeling. Despite his very helpful assistance and guidance, I stayed with the little guys. It wasn't until the summer of 2000, when I unexpectedly found myself with lots of "free" (that is unpaid) time, that my increased presence underwater led to an interest in the fish of our kelp forests. Fortunately they are usually much easier to identify than the marine algae, so this new interest wasn't too difficult.
One very large group of California fishes are the rockfish. Just to drop a few names, they include the black, black-and-yellow, blackgill, blue, brown, olive, copper, calico, rosy, vermilion, dusky, silvergrey, squarespot, aurora, redbanded, greenspotted, greenstriped, greenblotched, darkblotched, speckled, splitnose, sharpchin, rosethorn, shortbelly, cow, widow, yellowtail, yelloweye, flag, bank, honeycomb, pygmy, canary, kelp, grass, quillback, China, starry, halfbanded, stripetail, tiger... and the subject of this week's column, the gopher rockfish. Whew! They are very popular with fishers and make good subjects to photograph underwater as well... at least when the fishers have left any behind! This group has a number of species, often referred to generically as red snapper or rock cod, that have been seriously over-fished.
The rockfish, along with the treefish and bocaccio are actually members of the scorpionfish family. The gopher rockfish is found from Eureka, California, to San Roque, Baja California, Mexico. Although common in the central part of California's coastline (Mendocino to Pt. Conception), they are not as common to the north and in our region. These fish frequent rocky reefs with good caves and crevices for hiding places, and may be found down to 180 ft. Like some other species of rockfish, they often prop themselves up on a rock using their pectoral fins.The one I filmed for this column was observed at about 150 feet below Ship Rock on the outer wall. This may be an example of a colder water species found in deeper, colder water in our region.
Their body is olive-brown to brown in color with spots and blotches. Pictures in some of the field guides I used in researching this show a range of coloration and patterns. Gophers grow to nearly 16 inches in length (unless you are a fisher whose stories tell of the six footers that "got away!"). Dr. Milton Love, a former Cousteau associate and rockfish expert, says they may live to a maximum of 13 years... how fortunate for their parents, they barely make it into their teen years!
Gopher rockfish are solitary and territorial, generally staying within a given part of the reef. They are closely related to the black-and-yellow rockfish, although the two species differ in color. As Dr. Love points out, color alone is a poor way to differentiate between species. After all, humans come in many colors and we are all the same species (well, except for those green ones who are actually from Xanadu).
In parts of their range where they are found with their more aggressive relative, they seem to separate by depth with the gopher taking the deeper regions and the black-and-yellow the shallower. When two potentially competing species are found in the same area, they often divide or "partition" their habitat or resource use. Separating by depth is one method. Having one feed at night and the other by day is another example. Ecologists like myself refer to this as "niche partitioning."
This species mates in May and June. The young live up in the kelp fronds, but gradually drop to the bottom as they age and eventually leave the protection of the kelp. Young gopher rockfish feed on plankton including copepods and the larvae of crabs. The older members prefer adult crabs, shrimp, and an occasional fish or octopus for variety. They are rarely taken in our waters by party or private boats, but in central California may account for about 10% of the total recreational catch. Recently they have been targeted by commercial hook-and-line fishers for sale to fish markets and restaurants. Given my lack of culinary skills, I usually end up cooking fish Cajun style... blackened, very blackened! Maybe that explains why I prefer to write about "mating" rather than "munching!"
© 2006 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" or "Gentle Giants: Giant Sea Bass" DVD's. Yes, take Dr. Bill home with you... we'll both be glad you did!
A mature gopher rockfish at a depth of 150 feet off Ship Rock.
This document maintained by
Dr. Bill Bushing.
Material and images © 2006 Star Thrower Educational Multimedia