TRENDS IN FISHERIES and FISHERY RESOURCES ASSOCIATED WITH THE MONTEREY BAY NATIONAL MARINE SANCTUARY FROM 1981 – 2000 RICHARD M. STARR • JASON M. COPE • LISA A. KERR Published by the California Sea Grant College Program University of Calfornia, San Diego La Jolla, California 92093 www-csgc.ucsd.edu 2002 California Sea Grant is a statewide, multiuniversity program of marine research, education, and outreach activities, administered by the University of California. Sea Grant-sponsored research contrib- utes to the growing body of knowledge about our coastal and ocean resources and, consequently, to the solution of many marine-related problems facing our society. Through its Marine Extension Program, Sea Grant transfers information and technology developed in research efforts to a wide community of interested parties and users in California and throughout the nation. Sea Grant also supports a broad range of educational programs so that our coastal and ocean resources can be understood and used judiciously by this and future generations. The national network of Sea Grant programs is a unique partnership of public and private sectors, combining research, education, and outreach for public service. It is dedicated to meeting the changing environmental and economic needs in our coastal, ocean, and Great Lakes regions. A searchable data- base of publications from Sea Grant programs is available at the National Sea Grant Library: nsgd.gso.uri.edu. This work is sponsored in part by a grant from the National Sea Grant College Program, National Oceanic and Atmospheric Administration, U.S. Department of Commerce, under grant number NA06RG0142, project number A/P-1. The views expressed herein are those of the authors and do not necessarily reflect the views of any of those organizations. TRENDS IN FISHERIES and FISHERY RESOURCES ASSOCIATED WITH THE MONTEREY BAY NATIONAL MARINE SANCTUARY FROM 1981–2000 Richard M. Starr1 Jason M. Cope2 Lisa A. Kerr2 GIS analysis and maps provided by Jamie Kum3 ❐ ❐ ❐ ❐ ❐ ❐ ❐ ❐ 1University of California Sea Grant Extension Program 8272 Moss Landing Road Moss Landing, California 95053 2Moss Landing Marine Laboratories 8272 Moss Landing Road Moss Landing, California 95053 3California Department of Fish and Game 20 Lower Ragsdale Drive Monterey, California 93940 California Sea Grant College Program University of California La Jolla, California 92093-0232 www-csgc.ucsd.edu Publication No. T-046 ISBN 1-888691-09-3 EXECUTIVE SUMMARY isheries in Central California are part of this region’s rich cultural and economic history. In the last decade, however, catches of many fishery resources have greatly Fdeclined, due both to decreases in fish populations and to new regulations enacted to conserve or rebuild fish stocks. In this book, we summarize the technical concepts and informa- tion that fishery scientists use to estimate the population sizes of harvested species. In addition to summarizing scientific information, we also provide a brief description of the types of fisher- ies operating in the region encompassed by the Monterey Bay National Marine Sanctuary (MBNMS), and a summary of fishery management operations. Currently, more than 1,200 commercial vessels annually fish within the MBNMS bound- aries. This represents a decline of about 40% in the number of commercial fishing vessels working in this region since the early 1980s. Although the number of vessels has declined, total catches have increased as the commercial fishing industry targeted abundant pelagic species such as Pacific sardine and squid. Catches in recreational fisheries in this region grew by more than 60% from the 1960s to the 1980s. Recreational fishing effort increased by 65% in that same time frame. Since the late 1980s, however, both recreational catch and effort have fluctu- ated, but slightly declined. Nevertheless, recreational harvest exceeds commercial harvest for many nearshore species. Commercial landings of all species combined increased from 1981–2000. This trend is misleading, however, because it is due to the large increase in catches of small pelagic fishes and squid. The combined catch of all other species decreased by about 50% from the mid-1980s to the late 1990s. The decline in landings was directly related to reduced population sizes of many of the species inhabiting deep-water bottom habitats, caused by excessively high rates of fishing in the 1980s, when fishery scientists and resource managers overestimated the produc- tivity of stocks of bottom fish. Catches of nonpelagic fishes increased for a short time in the 1990s as a result of increased fishing in nearshore habitats; however, by the end of the 1990s, abundances of nearshore species had also declined. In the late 1990s, laws such as the federal Sustainable Fisheries Act, and California’s Marine Life Management Act (MLMA) and Marine Life Protection Act (MLPA) were passed that mandated more conservative management of marine resources. In response, federal resource managers reduced harvest rates on heavily fished species living in deep-water habi- tats. State resource managers also began to limit harvests of nearshore species. The full imple- mentation of these new laws will likely result in more restrictive regulations that are intended to minimize the chance of overfishing, limit bycatch, preserve essential fish habitat, and in some cases rebuild depleted stocks. In the short-term, these new regulations will probably result in a continued decline in the landings of many marine species harvested from MBNMS waters. Because many species with low population sizes co-occur with more abundant species, quotas for some healthy stocks will need to remain lower than necessary to protect stocks at risk. Also, because many of the fish species at risk are long-lived, grow slowly, and take a long time to reach maturity, it may take 10–20 years or more to see the results of current management regulations. The physical envi- ronment in the Monterey Bay region is very dynamic, however, and can have a strong influence on the population size of resident fish populations. There is some evidence that oceanographic conditions are changing back to a cooler, more productive environment in this region. If that i proves to be true, we may see more rapid rebuilding of cold-water stocks and a decline in the abundance of warmer water species. Historically, commercial and recreational fisheries have been regulated on a species by species basis. New ecological concepts, however, have led to an increased interest in managing fisheries using an approach that accounts for the importance of habitat in maintaining fish stocks. For that reason, we summarized the status of fishery resources in five major habitat types: 1) nearshore rocky reef and kelp, 2) nearshore soft bottom, 3) rocky deep shelf and slope, 4) soft bottom deep shelf and slope, and 5) open water habitats. Historically, nearshore rocky reef and kelp habitats were fished more heavily by recre- ational than commercial fisheries. Nearshore rocky areas became more important to commer- cial fisheries in the early 1980s, however, because of increased participation in the open-access hook-and-line fisheries, and later as a result of the more lucrative live-fish fishery. Rockfishes are the predominant component of catches in nearshore rocky reef and kelp habitats; about 15 rockfish species are commonly caught in these shallow areas. Annual commercial landings of fishes from shallow rocky habitats averaged about 730,000 lb/yr from 1991–98, almost twice that of the annual landings in the1980s. The high catches in nearshore reef and kelp habitats in the 1990s were probably not sustainable, and appeared to have reduced abundance of nearshore fishes in the MBNMS, as evidenced by declining catch rates. In the late 1990s, commercial landings declined in rocky nearshore habitats, due to a decrease in fish abundance and more restrictive fishery regulations. Commercial landings of some invertebrates also declined because of high harvest rates. Red abalone stocks were harvested to the point that the fishery was closed in 1997. Nearshore soft bottom habitats are home to many fishes and invertebrates, however the long-time exclusion of trawlers in the nearshore zone, and more recent ban of gill nets, have led to a limited and highly regulated fishing effort in this environment. Landings from nearshore soft bottom habitats averaged 14.3 million lb/yr from 1981–2000. Market squid are the main component of catches in these habitats, comprising more than 97% of the total landings. Fluc- tuations in squid landings and populations can be attributed primarily to market conditions and oceanographic changes such as El Niño events. Small sharks, white seabass, white croaker, surfperch, halibut, and several flatfish are the primary fish species caught in commer- cial and recreational fisheries in nearshore soft bottom habitats. Population sizes of most of these fish species are unknown, but there are indications that many of these populations are healthy in the MBNMS. Rockfishes are the principal component of commercial and recreational fisheries in rocky deep shelf and slope habitats in the MBNMS. Commercial landings from these habitats averaged 8.6 million lb/yr from 1981–2000. Semi-pelagic rockfish species such as bocaccio, chilipepper, widow rockfish, and yellowtail rockfish, comprised 98% of the total commercial catch from rocky deep shelf and slope habitats in the MBNMS. In the recreational fishery, almost 50% of the catch from 1959 to 1994 was taken from these habitats, and eight of the ten most numerous species taken in the Commercial Passenger Fishing Vessel (CPFV) fishery utilize deep rocky habitats. Conse- quently, fish populations in rocky deep shelf and slope habitats were the most heavily impacted by the high rates of fishing that occurred in the 1980s and early 1990s. Scientific stock assessments exhibit a range of population trends for rockfishes within rocky deep shelf and slope habitats along the West Coast of the United States. Stock assessments indicate stable or increasing trends in abundance for chilipepper and shortbelly rockfish.