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Appendix C Fisheries Case Studies This appendix discusses case histories for three important recre- ational fisheries in three different U.S. regions. These fisheries were chosen because they represent a range of scale and management intensity. (These histories were drawn from information available during the summer of 2005; therefore, they may no longer represent the current conditions. Nonetheless, these examples are useful to the larger dis- cussion.) The case history for lingcod (Ophiodon elongatus) represents a large-scale, federal stock assessment with coastwide management goals set by the Pacific Fishery Management Council (PFMC); however, in- season management is conducted by individual state agencies. The case history for red snapper (Lutjanus campechanus) in the Gulf of Mexico represents a large-scale fishery conducted in federal waters. Although management goals are annual, in-season management has failed in this fishery, and the Gulf of Mexico Fishery Management Council (GMFMC) actually evaluates management on the same schedule as the stock assessment--every three to five years. The case history for striped bass (Morone saxatilis) represents an east coast fishery conducted primarily in state waters with a coastwide stock assessment and annual management objectives set by a regional advisory board with individual states over- seeing annual management. 161
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162 APPENDIX C LINGCOD Life History The lingcod (Figure C.1) is the largest member of the greenling fam- ily. They occur from Kodiak Island, Alaska, to Baja California, Mexico, in depths to 475 meters (m) (1,558 feet [ft]) but usually shallower than 300 m (984 ft) in rocky habitats and kelp beds. They attain a maximum length of about 1.5 m (5 ft) and can weigh over 31.8 kilograms (kg) (70 pounds [lbs]). They are voracious predators on fish, shellfish, and octopus. Lingcod are considered non-migratory; although, tag data show some individuals may move great distances. Males and females tend to be separated by depth, with females preferring deeper water. Males guard egg clutches ("nests") until hatching, generally 711 weeks. During this period, the males are territorial and very susceptible to harvest. If the males are removed from the nest, other organisms consume the eggs. The maximum published age is 20; however, lingcod have been aged to 26 in Alaska.1 Richards et al. (1990) examine length and maturity relationships of lingcod from three areas in British Columbia and find that males begin to mature at 0.50 m (1.64 ft) and are all mature at 0.70 m (2.30 ft), and females begin to mature at 0.50 m (1.64 ft) and are all mature at 0.75 m (2.46 ft). Current Stock Status and Management Authority Lingcod along the U.S. west coast are managed as two distinct stocks: the Lingcod-North stock (Washington and Oregon) and the Lingcod-South stock (California). (Alaskan lingcod are not considered in this case study.) Both stocks are listed as overfished and are subject to a rebuilding plan. The latest assessment indicates that the lingcod stock has achieved its rebuilding objective of B40% in the north (actually 28 per- 2 cent above B40%) but was at B31% in the south. PFMC sets quotas 1 Personal communication, Kristen Munk, Alaska Department of Fish and Game, Juneau. 2 B represents the stock biomass (weight of a population of fish). The subscript represents the percent of the stock relative to its unfished biomass. B40%, a proxy for BMSY, is the biomass needed to sustain maximum sustainable yield (40 percent of the unfished biomass).
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APPENDIX C 163 FIGURE C.1 A young deckhand with a tagged lingcod (photo used with permission from Charlie Wilber). for lingcod fisheries, with in-season management by the individual states. Fishery Characteristics There are both recreational and commercial fisheries for lingcod, with recreational being particularly important in the southern area. In 2002, anglers landed 577 metric tons (mt) (1.3 million lbs) out of a total optimum yield (OY) of 577 mt (1.3 million lbs) and a total postseason catch estimated at 779 mt (1.7 million lbs) (51 percent over the coastwide OY). Private vessels and rental vessels accounted for most of the recreational catch, with the majority of the catch coming from Oregon and northern California. Charter and party boats accounted for 7 percent of recreational catch in Washington, 43 percent in Oregon, 32 percent in northern California, and 14 percent in southern California. Commercial lingcod fisheries along the west coast have been pre- dominately trawl fisheries. Recently, restrictions in trawl fisheries have
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164 APPENDIX C increased; therefore, roughly half of the commercial landings are now from hook and line. Coastwide commercial landings totaled 223 mt (492,000 lbs) in 2002 (Jagielo et al., 2003). Since 2004, PFMC has set two separate recreational fishery quotas for the two stocks. In 2003, California exceeded the entire west coast limit for lingcod that resulted in a coastwide late-season closure. Consequently, in 2004, PFMC set separate state fishery targets (Pacific Fishery Management Council, 2004); California is given statewide recreational allocation, and Oregon and Washington are given a combined recreational allocation. The recreational sector took 63 percent of the total catch, and the California recreational fishery took 61 percent of the coastwide recreational catch in 2004. In 2005, the recreational catch guidelines were 422 mt (930,000 lbs) for California, 151 mt (333,000 lbs) for Oregon, and 83 mt (183,000 lbs) for Washington. Size limits, bag limits, depth limits, and seasons vary by state and within state; in-season management action may be taken to prevent exceeding annual quotas. Oregon has committed to updating anglers on allowable catches on a monthly basis during the season so data on catch are required in a timely fashion. In-season changes are made in July if it appears that current catch rates will cause an in-season closure. Recreational Survey Methods The recreational fishery survey for lingcod is multifaceted. The Recreational Fisheries Information Network (RecFIN) program stores the survey data, the Marine Recreational Fisheries Statistics Survey (MRFSS) is used for the historical California data, field-intercept surveys are administered by the Pacific States Marine Fisheries Commission, and a random telephone survey of the coastal population is administered by a National Marine Fisheries Service (NMFS) contract. Additionally, there is the California Charter and Party Fishing Vessel effort survey (since 2001), the California Recreational Fisheries Survey (CRFS) (replaced the MRFSS in 2004), the Oregon Recreational Boat Survey, and Washington State's Ocean Sampling Program (OSP). The Oregon Recreational Boat Survey includes a field-intercept survey for effort and catch of private and rental boats and party and charter boats and a telephone survey of license holders for shore and estuary boat anglers, and OSP includes a seasonal exit count of vessels and an intercept sampling of catch.
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APPENDIX C 165 Stock Assessment Method The catch-at-age model used is a multiple-fleet, age-, and sex- structured model implemented in Coleraine (Jagielo et al., 2003). Cole- raine is a general age-structured model used for fish-stock assessment developed by Hilborn and colleagues; a manual and other information are available through the University of Washington (2004). Several weaknesses with the model include the lack of a recreational fishery catch per unit effort (CPUE) index. Although recreational catch accounts for most of the removals, recreational CPUE is problematic because catch rates may be affected by variable target species, undocumented search time, unreported discards, unknown spatial effort shifts, and bag limit effects (Jagielo et al., 2003). These problems will be exacerbated by changes in management, such as depth and seasonal closures. Information on discard and discard mortality is difficult to estimate but is important to the model. According to Jagielo et al. (2003): MRFSS has collected B1 (reported by angler to be dead) and B2 (reported by angler to be alive) catches since 1980. Estimates of lingcod discarded alive have in- creased substantially in response to (1) management changes in 1998 (the size limit increased from 22 to 24 inches) and (2) a seasonal closure in California waters beginning in 2000... It is interesting to note that esti- mates of fish discarded dead have decreased over time. Estimated live lingcod discarded in southern California was 306,000 fish in 2002. This compares to a total landed catch of 25,000 fish. [Washington Department of Fish and Wildlife] began collecting discard information from the recreational fishery in 2002 and estimated that 57 percent of the catch was discarded. [Washington Department of Fish and Wildlife] does not collect infor- mation on the portion of the catch discarded live or dead. Based on an earlier study..., the PFMC Groundfish Management Team used a 20 percent inflation factor to adjust landed catch to account for unobserved lingcod mortality in the commercial fishery beginning in 2002. Data collected by the Groundfish Observer program in 20012002 estimated that the percent discard of total observed catch was 78.8 percent. Because lingcod lack a
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166 APPENDIX C swim bladder, it is likely that there is a relatively good survival rate for these fish. In the models projecting future catch, both Washington and Oregon use 5 percent mortality for live discards, but this mortality is not incorporated into the current year assessment. There have been no formal studies of lingcod hooking mortality. Removals Recreational catch data for the lingcod assessment come from a variety of sources. For California, the RecFIN database (including the MRFSS) was used for 19801989 and 19932003. Oregon catch data were provided by the Oregon Department of Fish and Wildlife. Wash- ington catch data were obtained from the Washington Department of Fish and Wildlife (WDFW) OSP. Beginning in 2004, CRFS has been used in place of the MRFSS for California. Commercial catch data were compiled from agency reports and personal communication for all years preceding 1981. The Pacific Coast Fisheries Information Network (PacFIN) database was queried for catch information in subsequent years. Demographics The Lingcod-North population age data are available for recreational fisheries for 1980 and 19862002 with sample sizes ranging from 226 to 1098. The Lingcod-South population age data are available for recreational fisheries for 19921998 and 20002002 with sample sizes ranging from 48 to 545. Weight is estimated using a von Bertalanffy growth equation, which is updated periodically. Other sources used for size and age data include the commercial fisheries, the triennial trawl shelf survey, and the WDFW Cape Flattery Tag survey. The Stock Assessment Review Panel (STAR Panel) suggested that more emphasis needs to be placed on collecting biological data to improve fishery age, length, and sex samples sizes and to improve geographic coverage (Pacific Fishery Management Council, 2003).
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APPENDIX C 167 Abundance Indices The 2003 stock assessment for west coast lingcod uses commercial fishery and fishery-independent indices of abundance, such as the fol- lowing: · NMFS Triennial Shelf Trawl Survey (biomass and associated coefficients of variation) (This survey does not cover rocky habitat, a prime lingcod habitat and therefore has a habitat bias.) · WDFW Cape Flattery Tag Survey (length composition used as a recruitment index) · Trawl fishery logbook CPUE index Another index considered but not used is recreational CPUE, which was not used because of high index variability, lack of a discernable index trend, implausible temporal changes in abundance, and unresolved input data assumptions. Data from Washington did not contain discard information so there was no way to convert its data to total catch, which is important in estimating a CPUE trend. Also, Jagielo et al. (2003) find that "recreational CPUE data sets are often problematic for use as unbiased indices of abundance because catch rates may be affected by (1) variable target species by boat, (2) undocumented search time, (3) unreported discards, (4) unknown spatial effort shifts, and (5) bag limit effects." Because the recreational fishery now takes over 70 percent of the total catch of lingcod, the lack of an abundance index for this sector will continue to be problematic. Recommendations for Data Collection Jagielo et al. (2003) provide the following recommendations regard- ing data collection for this resource: · Improve fishery age-structure sampling size and geographic coverage · Conduct more frequent and synoptic fishery-independent surveys for stock indices and recruitment index · Analyze CPUE on a reef-specific basis for evaluation of an index of abundance
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168 APPENDIX C · Enumerate at-sea discards and mortality of released recreational fish coastwide to account for total mortality Economic and Social Information Commercial landings of lingcod have been reduced greatly in recent years by management actions. In 2004, 166 mt (366,000 lbs) of commercial lingcod were landed on the west coast for an ex-vessel (dockside) value of $412,000. No data are specifically available on the economic value of the recreational fishery for lingcod. In 2003, there were 1,283 angler trips directed for groundfish on the west coast and, of these, 325 were charter trips, and 958 were private vessel trips. RED SNAPPER Life History Red snapper (Figure C.2) are found along the Atlantic coast of North America from North Carolina to the Florida Keys and along the Gulf of Mexico from Florida to the Yucatan peninsula of Mexico (Robins et al., 1986). Adults are found in submarine gullies and depressions; over coral reefs, rock outcrops, and gravel bottoms; and are associated with oil rigs and other artificial structures (Gulf of Mexico Fishery Management Council, 2003). Eggs and larvae are pelagic while juveniles are found associated with bottom features or over barren bottom. Spawning occurs during the summer and fall over firm sand bottom with little relief away from reefs. Adult females mature as early as two years, and most are mature by four years (Schirripa and Legault, 1999). Red snapper have been aged up to 53 years, but most caught by the directed fishery are 2 to 4 years old (Wilson and Nieland, 2001). Current Stock Status and Management Authority The red snapper stock is in an overfished condition and continues to undergo overfishing (Gulf of Mexico Fishery Management Council, 2005a). This stock has been overfished since at least 1988. Currently,
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APPENDIX C 169 FIGURE C.2 Anglers with their red snapper (photo used with permis- sion from Jon G. Sutinen). it is under a rebuilding plan to end overfishing in 20092010 and to rebuild the stock to BMSY by 2032 (Gulf of Mexico Fishery Management Council, 2004a). The current population is now dominated by young fish, creating a low spawning potential ratio. In addition to the mortality associated with shrimp trawl bycatch, the population shows signs of overharvest in the directed fisheries, with truncated ages.3 GMFMC establishes management plans and regulates the recrea- tional red snapper fishery in U.S. federal waters. In the Gulf of Mexico, bag and minimum size limits and area and season closures are used. Individual states generally set regulations in state waters to comply with the federal regulations. However, Texas has a different recreational size limit and does not have a closed season to recreational fishing. Florida opens the recreational red snapper fishing season six days earlier than in federal waters. 3 Personal communication, Felicia Coleman, Florida State University, Talla- hassee.
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170 APPENDIX C Fishery Characteristics The red snapper fishery occurs predominately in federal waters. Red snapper have supported an important commercial fishery in the Gulf of Mexico for more than a century, with 6,400 mt (14.1 million lbs) landed in 1900. Documentation of the recreational fishery began on a regular basis in 1981 with the MRFSS. According to Schirripa (1999): Management of the red snapper resource has meant dividing the allowable fishing mortality between two competing fisheries: the directed fishery, which consists of a commercial and a recreational sector, and the undirected shrimp fishery. The shrimp fleet harvests age 0 and 1 red snapper in the form of bycatch. These vessels use bottom trawls to harvest shrimp, which share a propensity for the same habitat as juvenile red snapper. Although the discarded catch associated with shrimp trawls is not counted toward the [total allowable catch], it is included in the stock assessment as part of the total fishing mortality. In 1991, turtle excluder devices (TED) were mandated for all offshore shrimp boats operating in the Gulf of Mexico. In 1998 all offshore shrimp boats fishing in the western Gulf of Mexico were required to use some form of bycatch reduction device (BRD) as well. Several types of BRDs have been "certified" by the U.S. fishery management authorities as reducing red snapper bycatch by 30 percent to 50 percent with an approximate 4 percent to 6 percent reduction in shrimp loss. However, at present, BRDs are estimated to reduce red snapper bycatch by only 11.7 percent (Foster, 2004). Further reductions in overall red snapper bycatch may have occurred as a result of reductions in shrimping effort due to the depressed economic condition of the shrimp fishery and due to the loss of shrimp vessels and processors from Hurricanes Katrina and Rita in 2005.4 Red snapper is the most popular offshore recreational finfish fishery in the northern and western Gulf of Mexico with 49 percent of the di- 4Personal communication, Steven Atran, GMFMC, Tampa, Florida.
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APPENDIX C 171 rected fishery's total allowable catch (2,041 mt [4.5 million lbs] in 2005) allocated to the recreational sector. Fishing occurs off the coasts of Florida, Alabama, Mississippi, Louisiana, and Texas. More than 70 percent of the recreational catch is taken by the for-hire sector (Gulf of Mexico Fishery Management Council, 2004a). In addition to landed catch, more than half of all recreationally caught red snapper are released because of regulatory limits; release mortality for the recreational fishery is estimated to range from 15 to 40 percent (Gulf of Mexico Fishery Management Council, 2004b; Table C.1). Red snapper is listed as overfished; therefore, staying within the total allowable catch is particularly important (Gulf of Mexico Fishery Management Council, 2005a,b). During the 1990s and early 2000s, the recreational sector exceeded its allocation 10 out of 12 years, often significantly (Gulf of Mexico Fishery Management Council, 2004b). In response to such frequent and large overruns, Congress, in the Sustainable Fisheries Act of 1996, mandated that the recreational red snapper fishery in the Gulf of Mexico be managed in-season with a quota and that the fishery be closed when the quota is reached. In-season management was attempted during 19971999 using extrapolation of available data (Gulf of Mexico Fishery Management Council, 2005b). During this period, the annual recreational catch was based on the MRFSS, the Texas Parks and Wildlife Department's (TPWD) coastal sport fishing survey, and NMFS's head boat survey; discard information was collected in the MRFSS only. In-season management was difficult because the recreational catch data are not available for several months after collection. NMFS made projections of the recreational catch using average catch data from the previous two years from all three surveys. The data from the surveys done by Texas and NMFS were not available in-season. When available, the MRFSS data from the first two months of the current year replaced the projection for those two months, and this continued as current data became available but was limited to the first six months of the year; the last six months were estimated using previous years' data (Gulf of Mexico Fishery Management Council, 2005a). The recreational fishery was closed in-season with three weeks notice on November 27, 1997; September 30, 1998; and August 29, 1999; when the recreational sector was projected to have reached its share of the total allowable catch. These projections were not accurate, and the recreational sector overharvested its allocation by 20 percent in 1997, 29 percent in 1998, and 23 percent in 1999. In 2000, GMFMC abandoned in-season man- agement of the recreational sector and moved to a shorter season, larger
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174 APPENDIX C assessments where the number of fish discarded owing to minimum size limits was determined by the probabilistic method of Goodyear (1997) and then used along with indices of abundance in an age-structured model (ASAP or Virtual Population Analysis [VPA]). The discards from the recreational and commercial sectors during the open season were assumed to occur predominantly due to the regulations on minimum size. They were computed on a seasonal rather than annual basis to better accommodate the rapid growth exhibited by younger red snapper. Recreational catch data, recreational effort data, and age data from recreational samples are all inputs into this model. Since 1981, the annual recreational catch and effort estimates have been based on the MRFSS, TPWD's coastal sport fishing survey, and the NMFS head boat survey. Removals As stated in the Southeast Data, Assessment, and Review (SEDAR): Commercial landings statistics are the quantities and value of seafood products sold to established (licensed) wholesale and retail seafood dealers. Currently, these data are collected by trip ticket programs managed by the state fishery agencies in Florida, Alabama, and Louisiana [Gulf of Mexico Fishery Management Council, 2004b]. Dealers in Mississippi and Texas are required to submit monthly reports that provide quantity and value by species. Prior to the implementation of the trip ticket programs, landings statistics were collected by [NMFS] and state employees that visited the seafood dealers monthly and recorded the quantities and value purchased for each species for a calendar month. In addition, the agents would assign an estimate of the type of gear and fishing area where the landings were caught. The Southeast Fisheries Science Center (SEFSC) has maintained the commercial landings statistics (also known as general canvass landings statistics) in a re- gional database since the mid-1980s. The states provide the landings statistics from their trip ticket or monthly program to the SEFSC, and these data are summarized
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APPENDIX C 175 and maintained in the same format as the historical general canvass data. (Gulf of Mexico Fishery Manage- ment Council, 2004b) Directed commercial fishery discards are recorded on discard forms pro- vided as part of a mandatory logbook requirement. Recreational data were compiled for the three following sources: · The MRFSS (19811998) with some exceptions: (1) no wave 1 data in 1981, (2) no Texas boat mode in 19821984, (3) no Texas data after 1986, and (4) no head boat sampling after 1985 · NMFS's Beaufort Laboratory head boat survey for all states after 1985 · TPWD's coastal sport fishing survey Data on recreational discards were collected by the MRFSS but were not available for Texas landings or for landings from head boats. Red snapper catches from Texas only account for about 2 percent of the annual recreational landings gulfwide. Demographics According to Schirripa and Legualt (1999): Morphometric, growth, and other biological character- istics of red snapper were evaluated using a composite of length and other measurements of Gulf of Mexico red snapper that have been collected during research and monitoring programs through the years. The present evaluation combined the data from prior analyses with more recent observations from a variety of sources. A description of the earlier data and sources are given in Parrack (1986a, b) and Parrack and McClellan (1986), who obtained the data and prepared computer files of the various data sets. In addition, data collected during the trip intercept portions of the [MRFSS]; the [NMFS] head boat survey; and samples of commercial and recreational catches collected as part of the Trip Interview Program (TIP) of the State/Federal Cooperative Statistics Pro-
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176 APPENDIX C gram provided additional data sources. A biological profiles sampling program by the [NMFS] Panama City (Florida) Laboratory provided additional observations of growth and fecundity, as well as morphometrics. Addi- tional data were provided from research programs at the University of South Alabama, Louisiana State Univer- sity, the University of West Florida, and the Louisiana Universities Marine Consortium. Currently, there are only very limited data on sizes of live discards from the recreational sector. This is important because 60 percent of recre- ational catches are discarded gulfwide (Gulf of Mexico Fishery Management Council, 2004b). Abundance Indices Abundance indices include four fishery-dependent sources and three fishery-independent sources. The fishery-dependent indices are the commercial handline logbook data (directed and bycatch), including the eastern and western Gulf jig fishery and bottom longline data; bycatch of red snapper in shrimp trawl fishery (pre-1990 when bycatch could be sold); the MRFSS and TPWD's coastal sport fishing survey's CPUE data; and the head boat catch rates from the NMFS head boat survey. The fishery-independent indices are the Spatial Ecological Analysis of Megavertebrate Populations (SEAMAP) database for shrimp and bottomfish, for ichthyoplankton (under consideration as an index), and for reef fish (under consideration as an index). Economic and Social Information Red snapper is the most valuable commercial reef fish fishery in the Gulf of Mexico, with dockside landings worth over $9 million in 1998. Individual fishing quotas are being considered in the directed com- mercial fishery. Red snapper is also a very important recreational species in the Gulf of Mexico. Shifts in the recreational sector have occurred over the past two decades; in 1981 and 1982, private anglers landed about 65 percent of the recreational red snapper reported. However, presently, the for-hire sector lands over 70 percent of the recreational catch, with charter
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APPENDIX C 177 vessels taking most of this catch (Gulf of Mexico Fishery Management Council, 2004b). There are an estimated 3,220 recreational for-hire vessels in the Gulf of Mexico (Federal Register, 2002). GMFMC began notice of a federal for-hire sector moratorium in November 1998. Initial implementation occurred in 2001, but due to an error in the public notice, the application process was reopened in 2003 and again in 2005. The intent is to limit the for-hire sector to the March 29, 2001, participation level. Currently, approximately 1,554 vessels are licensed to participate in the moratorium for reef fish (Gulf of Mexico Fishery Management Council, 2005c). Compliance with the federal licensing requirement has increased with the development of the moratorium. STRIPED BASS Life History The Atlantic striped bass (Figure C.3) is a migratory species that ranges from the St. Lawrence River in Canada to the St. John's River in Florida. (The west coast population of striped bass, resulting from a few hundred fish introduced from the Navesink River in New Jersey to San Francisco Bay in the 1880s and now occurring from southern California to British Columbia, is not considered in this discussion.) This species can live up to 30 years and spends most of its adult life either in coastal estuaries or in the ocean, migrating north in the summer and south in the winter. Striped bass are anadromous, and in the spring, adults ascend rivers to spawn. Along the U.S. Atlantic coast, the major part of the migratory stock originates in the Chesapeake Bay spawning areas, with significant contributions from spawning grounds in the Hudson and Delaware Rivers. Fertilized eggs and larvae drift downstream to nursery areas in river deltas, inland portions of coastal sounds, and estuaries where they mature into juveniles. The juveniles remain in these areas for two to four years and then join the coastal migratory population. Females are highly fecund producing 0.5 million eggs at six years of age and 3 million at 15 years of age.
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178 APPENDIX C FIGURE C.3 Striped bass caught by young anglers in Maryland's Ches- apeake Bay (photo used with permission from the National Oceanic and Atmospheric Administration). Current Stock Status and Management Authority The striped bass population has been increasing steadily since 1982 and, in 2004, the population was estimated to be 11 million fish higher than the average stock size for the previous five years and 23.8 percent higher than the population in 2003. The 2003 year-class was estimated at 22 million fish at age 1 and is the largest year-class in the time series (19822003). The most recent full stock assessment (Northeast Fisheries Science Center, 2003) determined that, in 2002, the stock was not overfished and that overfishing did not occur. However, the Atlantic Striped Bass Technical Committee reported difficulty in determining if overfishing was occurring in 2003 because of divergent patterns in fishing mortality estimates from VPA and analysis of tagging data. The next scheduled full stock assessment will be in 2007.
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APPENDIX C 179 The implementation of the fishery management plan is mandatory under the Atlantic Striped Bass Conservation Act (P.L. 98-613). The Atlantic States Marine Fisheries Commission's (ASMFC) Striped Bass Management Board and Striped Bass Plan Review Team are responsible for monitoring the implementation of the fishery management plan. States are granted flexibility to deviate from the standards in the fishery management plan by submitting proposals for review by the ASMFC Striped Bass Technical Committee and Advisory Panel with approval from the ASMFC Management Board. Fishery Characteristics The fishery is limited to state waters (no catch allowed in federal waters). Much of the catch occurs in estuarine waters, but the MRFSS is limited to saltwater and, thus, not all estuarine landings are surveyed. In 2003, the total catch, including landings and discards, was estimated to be 4.7 million fish. The 2003 catch was above the 19962003 average of 4.0 million. Catch (2.4 million fish) and discards (1.2 million fish) from the recreational sector accounted for 76 percent of the total 2003 catch. Private and rental boats account for 80 percent of the recreational catch. Maryland accounted for the largest portion of the recreational fishery with 21.8 percent of total recreational landings, followed by Massa- chusetts (16.9 percent), Virginia (16.7 percent), New Jersey (16.3 per- cent), and New York (13 percent). The remaining states each landed 5 percent or less of the total recreational landings. In 2004, Massachusetts took 17 percent of the landed catch, followed by North Carolina and Maryland (Munger et al., 2005). Commercial catch (0.86 million fish) and discards (0.27 million fish) accounted for 24 percent of the total 2003 catch. Maryland commercial fisheries caught 50.8 percent of the total commercial landings, followed by Virginia (18.7 percent), the Potomac River Fisheries Commission (9.6 percent), New York (7.9 percent), and Massachusetts (6.4 percent). The remaining states each accounted for 4 percent or less of the total commercial landings. As of January 1, 2004, all states are required to implement a two-fish bag limit with a minimum size of at least 0.7 m (28 in) for their recreational fisheries. Chesapeake Bay fisheries, AlbemarleRoanoke fisheries, and states with approved conservation equivalency proposals are exempt from these rules. The first two areas have more conservative fishing mortality targets than those set by ASMFC and are allowed to set
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180 APPENDIX C their own seasons, harvest caps, bag limits, and size limits as long as their total catches stay below their targets. Recreational Survey Methods The MRFSS is used as a basis survey in most states. The shore and private and rental boat fishing modes are surveyed using the MRFSS coastal household telephone survey and the MRFSS intercept survey. The for-hire sector is surveyed using the Vessel Frame Telephone Survey, the Vessel Effort Validation Survey, and the MRFSS access- point intercept survey. Jurisdictions with significant recreational fisheries (Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Maryland, Virginia, and the Potomac River Fisheries Commission) are required to follow specific guidelines for supplementing the MRFSS collection of catch composition data and catch and effort information from these fisheries to achieve a 20 percent coefficient of variation, or propose specialized striped bass surveys to better assess recreational catch. Stock Assessment Method The striped bass population dynamics are modeled using an ADAPTVPA5 model and an integrated catch-at-age model. Both models consist of a sequential population model which incorporates catch-at-age time-series data and research vessel survey information. The major differences between the two methods are that the integrated catch- at-age model assumes that the catch-at-age data are measured with error, and separability patterns are estimated as parameters. Data from eight tagging programs, which are conducted by the U.S. Fish and Wildlife Service Cooperative Striped Bass Tagging Program and have been in progress for at least 11 years, were used to provide alternate estimates of fishing mortality. 5ADAPTVPA models are used extensively for fisheries stock assessments.
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APPENDIX C 181 Removals Given that the recreational fishery accounts for the largest portion of the striped bass catches, the MRFSS data are essential for accounting for total removals and for developing the catch-at-age information for the stock assessment. Total landings from the recreational striped bass fish- ery are calculated using type A+B1 records from the MRFSS. In 2003, these landings were estimated to be 2.4 million fish or 11,486 mt (25.3 million lb), with 80 percent accounted for by the private and rental mode in the MRFSS. Type B2 catch was estimated at 14.6 million fish. Size-at- age information on these discards indicate that it is the smaller fish that are generally released (peak at age 3; age range is 113 years). An 8 percent hooking mortality rate is assumed for recreational discards, resulting in an estimated loss of 1.2 million fish in 2003. Diodati and Richards (1996) examined mortality of striped bass hooked and released in saltwater. Predicted annual mortality averaged 9 percent and ranged from 3 percent under ideal conditions to 26 percent for the worst set of conditions. They found that surviving hooked fish had significantly lower physical condition factors than fish that had not been hooked. The 2004 Striped Bass Stock Assessment Technical Committee ex- pressed concern that there was considerable error in the catch produced by the MRFSS in 2003. The MRFSS estimated increases in some of the waves even though fishing effort was reported to have decreased due to hurricanes. On the other hand, there was also concern that the harvest had been underestimated because the winter fisheries (wave 1) in North Carolina and Virginia were not covered. Estimates of commercial discards for striped bass rely on direct measurements from fisheries in the Hudson River Estuary and Delaware Bay and River and tagging information for the other areas. Since 1982, estimates for the other areas have been based on the ratio of tags reported from the discarded fish in the commercial fishery to tags reported from discarded fish in the recreational fishery, scaled by total recreational discards. Demographics Length and weight measurements usually are recorded by intercept interviewers for type A fish catch records. These data have been used to develop catch-at-length and catch-at-age estimates. Length frequencies of recreational landings for striped bass were based on a combination of
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182 APPENDIX C the MRFSS length samples and volunteer angler logbooks. The age compositions of the recreational catch for each state were estimated using state specific agelength keys. Lengths from the volunteer angler logbooks and the American Littoral Society data were used to estimate the age composition of the recreational discards. For the striped bass assessment, mean weights-at-age in the 2003 catch were determined from Maine and New Hampshire recreational harvest and discards; Massachusetts recreational and commercial catch; Rhode Island recreational and commercial catch; Connecticut recre- ational catch; New York recreational catch and commercial landings; New Jersey recreational catch; and Delaware, Maryland, Virginia, and North Carolina recreational and commercial catches. Abundance Indices Indices of abundance for striped bass represent both fishery- independent and fishery-dependent sources. There are seven sets of fishery-independent indices used for the adult population: the Maryland gillnet survey of the spawning population (ages 213+), Virginia pound net CPUE (ages 213+), New York ocean haul seine (ages 313+), Northeast Fisheries Science Center spring inshore survey (ages 313+), and three age-aggregated trawl indices from Connecticut (ages 26), New Jersey (ages 2+), and Delaware (ages 27). Juvenile surveys produce indices of young-of-year (age 0) in Maryland, Virginia, New York, and New Jersey as well as age 1 indices for Maryland and Long Island, New York. The fishery-dependent indices represent a mix of commercial and recreational fishing data, including the Massachusetts commercial catch per trip (ages 713+) and the Connecticut volunteer angler catch per trip (ages 213+). Altogether, these data sources represent 55 age-specific indices that are used in the ADAPTVPA model. The MRFSS estimates of catch rate are not used in the striped bass assessment, although the time series of these catch rates have been compared with trends from VPA by the technical committee and found to be similar in recent years.
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APPENDIX C 183 Economic and Social Information Amendment 6 of the Interstate Fisheries Management Plan for At- lantic Striped Bass states that the Atlantic Coast Cooperative Statistics Program will require the collection of baseline social and economic data on all recreational fisheries through add-ons to existing recreational catch and effort surveys (Atlantic States Marine Fisheries Commission, 2003). This information is defined in the Atlantic Coast Cooperative Statistics Program documents as follows: Economic information includes information on market conditions in commercial fisheries (price and value information), as well as complementary information on recreational fisheries. Social sciences information is typically broader sources of information specific to commercial and recreational fishermen, their families, and the fishing community in general. For many man- aged fisheries economic and social sciences information is not available and is provided in an informal manner by fishermen during public comment periods. At times, this information is viewed as anecdotal and may be difficult to use in the fishery management decision-making process. (Atlantic States Marine Fisheries Com-mission, 2003)
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Representative terms from entire chapter: