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    Biological characteristics of the catch from the 1985-86 Pacific herring, Clupea harengus pallasi, roe fishery in California

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    In Tomales Bay, 4-, 5-, and 6-yr-old herring, Clupea harengus pallasi, composed 70% by number of the 1985-86 season's catch. In San Francisco Bay, 2-, 3-, and 4-yr-old herring composed 78% by number of the roundhaul catch, and 4- and 5-yr-old herring composed 64% by number of the gill net catch. The percent of 4-yr-old herring in both the Tomales Bay catch (25% and San Francisco Bay gill net catch (39%) is at a high level for the second year in a row. Recruitment of 2-yr-old herring into the San Francisco Bay roundhaul fishery was about average, with 2-yr-old herring composing 33% of the catch. The mean length of herring in the San Francisco Bay roundhaul catch increased to 178 mm BL, while the mean length of the gill net catch remained 196 mm BL. The mean length of the Tomales Bay catch decreased to 198 mm BL due to the increased number of 3- and 4-yr-old herring in the catch. (18pp.

    Southern California marine sport fishing from privately owned boats: catch and effort for October-December 1982

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    The catch landed and effort expended by private-boat sport fishermen were studied in southern California marine waters between October and December 1982, to determine the impact of one segment of the sport fishery on local marine resources. Fishermen returning from fishing trips were interviewed at launch ramps, hoists, and boat-rental facilities. This report contains quantitative data and statistical estimates of total effort, total catch, catch of preferred species, and length frequencies for those species whose catches are regulated by minimum size limits. An estimated 157,000 organisms were landed by 57,700 anglers and 4800 divers. The major components of the angler catch were Pacific mackerel, Scomber japonicus (28,700 estimated catch): white croaker, Genyonemus lineatus (24,000 estimated catch); and Pacific bonito, Sarda chiliensis (16,700 estimated catch). These three species represented almost half the total estimated angler catch. Rockfishes, Sebastes spp: were a major catch component; the 35 rockfish species landed made up 24% of the estimated catch. Divers landed an estimated 14,700 fishes and invertebrates. Chief among these were abalone, Haliotis spp. (4200 estimated catch); rock scallop, Hinnites rugosus (3600 estimated catch); and California spiny lobster, Panulirus interruptus (2500 estimated catch). Angler and diver compliance with size-limit regulations was generally favorable, with diver compliance being particularly scrupulous, especially with invertebrate species. The compliance rate for California halibut, Paralichthys californicus, showed a drop from the previous quarter (July - September 1982) from 70 to 59% legal. During the same time period, size-limit compliance rose from 4 to 20% for Pacific bonito, a species with a tolerance allowing the take of some under-sized fish. (28p.

    The U.S. Gulf of Mexico Pink Shrimp, Farfantepenaeus duorarum, Fishery: 50 Years of Commercial Catch Statistics

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    U.S. Gulf of Mexico, pink shrimp, Farfantepenaeus duorarum, catch statistics have been collected by NOAA’s National Marine Fisheries Service, or its predecessor agency, for over 50 years. Recent events, including hurricanes and oil spills within the ecosystem of the fishery, have shown that documentation of these catch data is of primary importance. Fishing effort for this stock has fluctuated over the 50-year period analyzed, ranging from 3,376 to 31,900 days fished, with the most recent years on record, 2008 and 2009, exhibiting declines up to 90% relative to the high levels recorded in the mid 1990’s. Our quantification of F. duorarum landings and catch rates (CPUE) indicates catch have been below the long-term average of about 12 million lb for all of the last 10 years on record. In contrast to catch and effort, catch rates have increased in recent years, with record CPUE levels measured in 2008 and 2009, of 1,340 and 1,144 lb per day fished, respectively. Our regression results revealed catch was dependent upon fishing effort (F=98.48df=1, 48, p<0.001, r2=0.67), (Catch=1,623,378 + (520) × (effort)). High CPUE’s measured indicate stocks were not in decline prior to 2009, despite the decline in catch. The decrease in catch is attributed in large part to low effort levels caused by economical and not biological or habitat related conditions. Future stock assessments using these baseline data will provide further insights and management advice concerning the Gulf of Mexi

    Biological characteristics of the catch from 1984-85 Pacific herring, Clupea harengus pallasi, roe fishery in California

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    In Tomales Bay, 5-, 6-, and 7-yr-old herring, Clupea harengus pallasi, composed 75% by number of the 1984-85 season's catch. In San Francisco Bay, 2-, 3-, and 4-yr-old herring composed 82% by number of the roundhaul catch, and 5-, 6-, and 7-yr-old herring composed 68% by number of the gill net catch. The percent of 4-yr-old herring increased to a record high level in the San Francisco Bay gill net catch. Recruitment of 2-yr-old herring into the San Francisco Bay roundhaul fishery was excellent, with 2-yr-old herring composing 41% of the catch. The growth rate of herring improved in both Tomales and San Francisco Bays, after the period of poor growth during the recent El Nino, when the weight of herring averaged 20% below normal. (23pp.

    Repeated use of green-manure catch crops in organic cereal production - grain yields and nitrogen supply

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    By restricted access to manure, nitrogen (N) supply in organic agriculture relies on biological N-fixation. This study compares grain yields after one full-season green manure (FSGM) to yields with repeated use of a green-manure catch crop. At two sites in south-eastern Norway, in a simple 4-year rotation (oats/wheat/oats/wheat), the repeated use of ryegrass, clover, or a mixture of ryegrass and clover as catch crops was compared with an FSGM established as a catch crop in year 1. The FSGM treatments had no subsequent catch crops. In year 5, the final residual effects were measured in barley. The yield levels were about equal for grains with no catch crop and a ryegrass catch crop. On average, the green-manure catch crops increased subsequent cereal yields close to 30%. The FSGM increased subsequent cereal yields significantly in two years, but across the rotation the yields were comparable to those of the treatments without green-manure catch crop. To achieve acceptable yields under Norwegian conditions, more than 25% of the land should be used for full-season green manure, or this method combined with green-manure catch crops. The accumulated amount of N in aboveground biomass in late autumn did not compensate for the N removed by cereal yields. To account for the deficiency, the roots of the green-manure catch crops would have to contain about 60% of the total N (tot-N) required to balance the cereal yields. Such high average values for root N are likely not realistic to achieve. However, measurement of biomass in late autumn may not reflect all N made available to concurrent or subsequent main crop

    Onboard sampling of the rockfish and lingcod commerical passenger fishing vessel industry in northern and central California, 1992

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    In 1992 fishery technicians sampled 230 commercial passenger fishing vessel (CPFV) trips targeting rockfish and lingcod from the port areas of Fort Bragg, Bodega Bay, San Francisco, Monterey, and Morro Bay. The skippers of 44 vessels, and 2,190 anglers, cooperated in the study. Species composition by port area and month, catch-per-unit-effort, mean length, and length frequency of lingcod and the 18 most frequently observed rockfish species are presented, as well as fishing effort relative to time, depth, and distance from port. Total catch estimates based on unadjusted and adjusted logbook records are summarized. Average catch of kept fish per angler day was 12.6 and average catch of kept fish per angler hour was 4.0. A continuing trend of an increasing frequency of trips to deep (> 40 fm) locations was observed in the Bodega Bay, San Francisco, and Monterey areas. Bodega Bay and San Francisco showed the highest frequency of trips to distant locations. Sixty species comprised of 29,731 fish were observed caught during the study. Rockfish comprised 93.5% by number of the total observed catch. The five most frequently observed species were blue, yellowtail, widow and rosy rockfishes, and bocaccio, with lingcod ranking eighth. CPFV angler success, as determined by catch per angler hour, generally increased in all ports in 1992 compared to previous 1988-91 data (Reilly et al. 1993). However, port-specific areas of major concern were identified for chilipepper, lingcod, and black rockfish, and to a lesser extent brown, canary, vermilion, yelloweye, widow and greenspotted rockfishes. These areas of concern included steadily declining catch rate, steadily declining mean length, and/or a high percentage of sexually immature fish in the sampled catch. Recent sampling of the commercial hook-and-line fishery in northern and central California indicates that most rockfishes taken by CPFV anglers are also harvested commercially. (105pp.

    Biological characteristics of the catch from the 1986-87 Pacific herring, Clupea harengus pallasi, roe fishery in California

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    In Tomales Bay, 4-, 5-, and 6-yr-old herring, Clupea harengus pallasi, composed 85% by number of the 1986-87 season's catch. In San Francisco Bay, 2-, 3-, and 4-yr-old herring composed 88% of the roundhaul catch, and 4-, 5-, and 6-yr-old herring composed 86% by number of the gill net catch. The age composition of both the Tomales Bay and San Francisco Bay gill net catch has shifted to primarily 4-, 5-, and 6-yr-old herring. Recruitment of 2-yr-old herring into the San Francisco Bay roundhaul fishery was good, with the 1985 yr class composing 37% of the catch. The mean length of herring in the San Francisco Bay roundhaul catch decreased to 174 mm BL, and the mean length of the gill net catch decreased to 194 mm BL. The mean length of the Tomales Bay catch also decreased to 197 mm BL. Average weight at age of Tomales Bay herring is below average for the fourth consecutive year. In San Francisco Bay the average weight at age is above average, even though length at age declined slightly. (20pp.
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