species specifics

BY CHUGEY SEPULVEDA, PhD, AND SCOTT AALBERS, M.S. currently average around one fifth of the CALIFORNIA HALIBUT 4.7 million pounds landed back in 1919. (PARALICHTHYS CALIFORNICUS) Peak commercial landings rapidly declin- ed to a low of 950,000 pounds in 1932. Stock depletion has been attributed to both over-fishing and alterations of nur- sery habitat (bays and estuaries). Com- mercial halibut landings in California currently average around one million pounds annually, and these fish are har- vested using bottom trawls, set gillnets, and hook-and-line. Trawl and gillnet fish- eries are highly regulated through size (22-inch limit), gear (minimum mesh size of 8.5 inches), season (closed March 15th alifornia halibut belong to the family of large-toothed through June 15th), and area restrictions, flounders (Paralichthyidae), just one of the 11 families with no gear allowed within three miles of flatfishes. Flatfish are comprised of more than 700 of the coast or one mile of the Channel species and are commonly referred to as flounder, sole, Islands. In recent years, commercial hook- halibut, turbot, fluke, plaice, sand dabs, and tonguefish. and-line fisheries have gained populari- C ty, with up to 20 percent of annual land- They are easily identifiable with a lateral- pecting prey while lying camouflaged on ings caught with hook-and-line gear. ly compressed body and both eyes on the bottom under a dusting of sand. Back in 1971, a minimum size of 22 the same side of an asymmetrical head. Mature halibut feed primarily on an- inches was also instated for the recre- In some families (Pleuronectidae), the eyes chovies, sardines, top smelt, grunion, ational fishery, with fillets needing to be are always on the right side of the body, white croaker, and squid. These fish are at least 16 3/4 inches in length with the and in other families (Bothidae) eyes are relatively slow-growing, reaching seven skin intact. In addition, recreational fish- always on the left. Although the Califor- to nine inches and about one pound in ers are limited to a daily bag limit of five nia halibut is classified in the group of their first year of life. In general, females California halibut south of Point Sur and left-eyed flounders, this species is unique grow more rapidly and attain larger sizes only three halibut per day when fishing in that about half of California halibut than male halibut. Male halibut mature north of Point Sur. consist of right-eyed individuals. When at around two to three years, whereas With increasing concerns over water larval halibut are approximately one most females reach sexual maturity at quality, and an awareness of the need for month old, the right or the left eye begins approximately four years of age and 15 estuarine habitat restoration, it may be to migrate to the other side of the head. to 17 inches. A 22-inch female is around that the halibut will be among the many Once the eye has completely migrated five or six years old, while males require species to benefit from our society’s push (approximately six weeks) and their head about another year to reach this legal to clean up and conserve our inshore wat- morphology has changed, the young juv- size. Halibut are relatively long-lived, erways. By comparing the historical land- eniles are ready to settle out to the bottom. capable of reaching 30 years of age. ings of the early 1900s to those of today, Following metamorphosis at approxi- To spawn, mature halibut move in- it is obvious that we have a long way to mately one half of an inch in size, halibut shore from February through July, with go before the stock is in the condition it larvae typically settle out within embay- peak spawning in May along shallow once was. However, given the stringent ments or along shallow sandy beaches. stretches of sandy coastline. Spawning regulations currently in place on all stake- Shallow bays and estuaries offer critical season typically coincides with periods holders, it is likely that we will see better nursery habitat for young juveniles to of heightened fishing pressure in south- halibut fishing in the years to come. feed and evade predators. Newly settled ern California. Likely due to their faster halibut feed primarily on crustaceans, in- growth rates, larger halibut tend to be PIER is a non-profit 501(c)3 research insti- cluding copepods and amphipods, until female, and in California females com- tute dedicated to scientific research, educa- they reach approximately 2.5 inches in prise a greater fraction of the commercial tion and the sustainable management of the length. Juveniles become increasingly pis- landings (60 to 80 percent). marine environment. Special thanks are offered civorous (feeding on fish) with size and to Mr. Thomas Pfleger and Family, Darryl primarily eat gobies and other small fish. Fisheries Lewis and the Harris Foundation, Thomas Adult halibut feed predominantly over California halibut continue to support Jay Fullam, Lorraine Bohnet and Vicki Win- sandy bottoms from the surf line out to valuable commercial and recreational trode. To read more about PIER research proj- 50 fathom, and they will ambush unsus- fisheries, although annual catch rates ects please visit us at www.pier.org. I

66 | PCSportfishing.com | THINK CONSERVATION | JUNE 2009