species specifics

BY CHUGEY SEPULVEDA, Ph.D., AND SCOTT AALBERS, M.S.

CHUB MACKEREL (Scomber japonicus) Photo by Bob Hoose hub mackerel, also known as Pacific mackerel, is a prolific coastal pelagic species that occurs throughout temperate regions around the globe. Belonging to the C tuna family (Scombridae), a group of fishes with several adaptations for increased swimming performance (i.e., high deg- ree of streamlining, deeply forked caudal fin, finlets), this species is a valuable resource for several nations, including the U.S., and plays a key role in Southern California as an important forage species for higher trophic levels. BIOLOGY a highly varied diet that includes cope- In the eastern Pacific, chub mackerel pods, euphausids (krill), small fishes, range from Chile to the Gulf of Alaska, and squid. where they provide an important link To defend against the wide variety of in marine food webs between plank- predators that rely on mackerel as part tonic organisms and predatory fishes, of their diet, juvenile mackerel begin to marine mammals, and sea birds. They form structured schools at just over one are opportunistic feeders, particularly inch in size. In southern California many during the larval and juvenile stages, of our coastal game fishes, such as white when they feed upon a wide variety of seabass, yellowtail, giant seabass, tunas, zooplankton. Juvenile chub mackerel dorado, striped marlin, and pelagic are voracious feeders and grow rapidly, sharks, rely heavily on the chub mack- particularly during the spring and sum- erel resource. As juveniles, chub mack- mer months. Adult mackerel also have erel often develop multi-species schools

84 | PCSportfishing.com | THINK CONSERVATION | SEPTEMBER 2011 with other coastal pelagic species, such erel supported one of California’s most as Pacific sardines, jack mackerel, and lucrative fisheries during the 1930s and sometimes eastern Pacific bonito. 1940s, with up to 75,000 tons landed Under optimal oceanic conditions, annually. During this time, the chub chub mackerel can reach 12 inches and mackerel ranked second to Pacific sar- over a pound in size during their sec- dines in California landings; however, ond year of life. At this size most males by 1970 managers considered the stock are already mature, while the majority severely depleted, and the purse-seine of females reach maturity in their third fishery was shut down until stocks year of life. Growth slows considerably rebounded in 1977. Furthermore, dur- in mature individuals, as much of their ing this period, purse seine vessels shift- energy stores are allocated towards repro- ed towards targeting anchovies, sar- ® duction. Spawning can occur through- dines, jack mackerel, and bonito. Since BX2-50 BX2-30 • Line Capacity: 60lb/500yds Line Capacity: 50lb/400yds out the entire year in some regions (i.e. the commercial fishery reopened in • Wt: 41Oz. Wt: 36Oz. Peru), though along the California coast 1977, mackerel harvest off of California $649 $629 chub mackerel mostly spawn from has been strictly monitored under a • Patented TwinDrag™ System April through August when water tem- quota-based system, with several addi- • Seven Class 5 ABEC stainless steel bearings peratures range from 60 to 70 degrees tional fishery regulations in place. Dur- • Greased AccuDrag system • Titanium friction washers Fahrenheit. Females typically spawn ing the commercial moratorium, recre- • Stainless steel gears multiple times during the same season, ational catches of mackerel far exceed- producing thousands of eggs, depend- ed commercial take, with over one mil- We only carry products that we believe ing on fish size and nutritional condi- lion fish harvested annually. Mackerel in and can sell at an affordable price. tion. Although chub mackerel are capa- continue to rank among the top 10 Advancing the joy of fishing to every ble of spawning every night (under species caught in Southern California individual, one reel at a time. optimal nutritional and oceanic condi- recreational fisheries, although catches 19031 Bushard St., Huntington Beach, CA 92646 tions), females typically spawn, on have declined since the early 1980s. www.MahiTackle.com average, every 10 days. The oldest aged On a global scale, California fisheries 800-930-8048 chub mackerel off California was 12 harvest only a small fraction of the total [email protected] years old with a maximum size of 25 chub mackerel landings. World land- No Sales Tax outside of CA inches and over six pounds. ings of chub mackerel peaked at more than three million tons in 1978 and MOVEMENTS have since fluctuated around two mil- In the eastern north Pacific, chub mack- lion tons annually. Areas with the largest erel are most abundant from Point reported catches of chub mackerel in- Conception down to Cabo San Lucas, clude the coast of Peru, northwestern Mexico, in water temperatures ranging Africa, northeastern Russia, and China. from 50 to 72 degrees Fahrenheit. Sea- Although the chub mackerel fishery is sonal migrations have not been con- closely monitored in the U.S., interna- firmed with tagging studies, but fish- tional management is critical. eries data for this region suggests that Despite the economic and ecological mackerel schools tend to move towards importance of the chub mackerel re- the north as water temperatures increase source, we still lack information on the during summer months and southwards factors that affect recruitment, the pre- during the winter. Similarly, reported cise nature of the movements of this catches of chub mackerel tend to occur species, and how the stock is influenced farther north during warm-water years by various oceanic conditions. or El Niño conditions. Primarily found over the continental shelf, chub mack- Information provided by the California erel also occur offshore, from the sur- Department of Fish and Game, California’s face to around 1,000 feet in depth. Living Marine Resources (2001). PIER is a non-profit 501(c)3 research institute dedi- FISHERIES cated to scientific research, education, and Although chub mackerel are harvested the sustainable management of the marine with a variety of fishing gears, purse environment. Special thanks are offered seine nets are the primary gear used to to Mr. Thomas Pfleger and Family, the capture this coastal resource. Purse seine George T. Pfleger Foundation, the Harris fisheries mainly harvest two- to four- Foundation, Tommy Fullam, Cindy Jonas- year-old fish, most of which is canned son, and Vicki Wintrode. To read more and sold to international markets. With about PIER research projects, please visit the onset of purse seining, chub mack- www.pier.org.

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