995 resultados para Salmon fisheries


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Knowledge of the distribution and biology of the ragfish, Icosteus aenigmaticus, an aberrant deepwater perciform of the North Pacific Ocean, has increased slowly since the first description of the species in the 1880’s which was based on specimens retrieved from a fish monger’s table in San Francisco, Calif. As a historically rare, and subjectively unattractive appearing noncommercial species, ichthyologists have only studied ragfish from specimens caught and donated by fishermen or by the general public. Since 1958, I have accumulated catch records of >825 ragfish. Specimens were primarily from commercial fishermen and research personnel trawling for bottom and demersal species on the continental shelves of the eastern North Pacific Ocean, Gulf of Alaska, Bering Sea, and the western Pacific Ocean, as well as from gillnet fisheries for Pacific salmon, Oncorhynchus spp., in the north central Pacific Ocean. Available records came from four separate sources: 1) historical data based primarily on published and unpublished literature (1876–1990), 2) ragfish delivered fresh to Humboldt State University or records available from the California Department of Fish and Game of ragfish caught in northern California and southern Oregon bottom trawl fisheries (1950–99), 3) incidental catches of ragfish observed and recorded by scientific observers of the commercial fisheries of the eastern Pacific Ocean and catches in National Marine Fisheries Service trawl surveys studying these fisheries from 1976 to 1999, and 4) Japanese government research on nearshore fisheries of the northwestern Pacific Ocean (1950–99). Limited data on individual ragfish allowed mainly qualitative analysis, although some quantitative analysis could be made with ragfish data from northern California and southern Oregon. This paper includes a history of taxonomic and common names of the ragfish, types of fishing gear and other techniques recovering ragfish, a chronology of range extensions into the North Pacific and Bering Sea, reproductive biology of ragfish caught by trawl fisheries off northern California and southern Oregon, and topics dealing with early, juvenile, and adult life history, including age and growth, food habits, and ecology. Recommendations for future study are proposed, especially on the life history of juvenile ragfish (5–30 cm FL) which remains enigmatic.

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William Francis Thompson (1888–1965), an early fishery biologist, joined the California Fish and Game Commission in 1917 with a mandate to investigate the marine fisheries of the state. He initiated studies on the albacore tuna, Thunnus alalunga, and the Pacific sardine, Sardinops sagax, as well as studies on other economically important marine organisms. Thompson built up a staff of fishery scientists, many of whom later attained considerable renown in their field, and he helped develop, and then direct, the commission’s first marine fisheries laboratory. During his tenure in California, he developed a personal philosophy of research that he outlined in several publications. Thompson based his approach on the yield-based analysis of the fisheries as opposed to large-scale environmental studies. He left the state agency in 1925 to direct the newly formed International Fisheries Commission (now the International Pacific Halibut Commission). William Thompson became a major figure in fisheries research in the United States, and particularly in the Pacific Northwest and Alaska, during the first half of the 20th cent

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Recreational creel survey data from 28,923 intercepts collected from Biscayne National Park, Florida and surrounding waters were analyzed for January 1976 through July 1991, prior to disruptions caused by Hurricane Andrew in 1992. A total of 261,268 fish and shellfish representing 170 species or higher taxa were recorded. The average trip landed 9.03 fish and/or shellfish. Mean annual landings per angler were 4.77 fish/angler/trip (from 3.8 in 1991 to 5.83 in 1981) and dropped significantly for each of the 2 years following Florida's adoption of mutiple new minimum size limits in 1985 and 1990. The relative contribution to total numerical landings by recreational party type were: skilled anglers (34.0%), food (19.8%), family (14.5%), novice (11.5%), spearfishing (10.3%), lobstering (9.6%), and other (0.3%). FIve species or higher taxa accounted for more than 50% of total landings by number: white grunt, Haemulon plumieri, 15.8%; spiny lobster, Panulirus argus, (10.6%; gray snapper, Lutjanus griseus, 10.6%; unidentified grunts, Haemulon spp., 7.3%; and dolphin, Coryphaena hippurus, 6.6%. An average of 4.39 fish or shellfish were reported released per trip. Five taxa accounted for 67% of all releases. Lobster divers reported the highest average release rate (5.73 per trip) and spearfishing the lowest (0.70 per trip). The ratio of releases to landings was 0.49:1 for all taxa, but ranged from 0.03:1 for dolphin to 1.19:1 for unidentified grunts. Spearfishing accounted for 12.0% of the total fishing trips sampled but only 10.3% of the total number organisms landed and 7.6% of all organisms caught. Hogfish, Lachnolaimus maximus, accounted for 49% if total spearfishing landings (13,286 of 27,015) and 84.3% of total 15,762 hogfish landed.

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This paper provides the first description of the mangrove cockle, Anadara spp., fisheries throughout their Latin American range along the Pacific coast from Mexico to Peru. Two species, A. tuberculosa and A. grandis, are found over the entire range, while A. similis occurs from El Salvador to Peru. Anadara tuberculosa is by far the most abundant, while A. grandis has declined in abundance during recent decades. Anadara tuberculosa and A. similis occur in level mud sediments in mangrove swamps, comprised mostly of Rhizophora mangle, which line the main-lands and islands of lagoons, whereas A. grandis inhabits intertidal mud flats along the edges of the same mangrove swamps. All harvested cockles are sexually mature. Gametogenesis of the three species occurs year round, and juvenile cockles grow rap-idly. Cockle densities at sizes at least 16–42 mm long ranged from 7 to 24/m2 in Mexico. Macrofaunal associates of cockles include crustaceans, gastropods, and finfishes. The mangrove swamps are in nearly pristine condition in every country except Honduras, Ecuador, and Peru, where shrimp farms constructed in the 1980’s and 1990’s have destroyed some mangrove zones. In addition, Hurricane Mitch destroyed some Honduran mangrove swamps in 1998. About 15,000 fishermen, including men, women, and children, harvest the cockles. Ecuador has the largest tabulated number of fishermen, 5,055, while Peru has the fewest, 75. Colombia has a large number, perhaps exceeding that in Ecuador, but a detailed census of them has never been made. The fishermen are poor and live a meager existence; they do not earn sufficient money to purchase adequate food to allow their full health and growth potential. They travel almost daily from their villages to the harvesting areas in wooden canoes and fiberglass boats at low tide when they can walk into the mangrove swamps to harvest cockles for about 4 h. Harvest rates, which vary among countries owing to differences in cockle abundances, range from about 50 cockles/fisherman/day in El Salvador and Honduras to 500–1,000/ fisherman/day in Mexico. The fishermen return to their villages and sell the cockles to dealers, who sell them mainly whole to market outlets within their countries, but there is some exporting to adjacent countries. An important food in most countries, the cockles are eaten in seviche, raw on the half-shell, and cooked with rice. The cockles are under heavy harvesting pressure, except in Mexico, but stocks are not yet being depleted because they are harvested at sizes which have already spawned. Also some spawning stocks lie within dense mangrove stands which the fishermen cannot reach. Consumers fortunately desire the largest cockles, spurning the smallest. Cockles are important to the people, and efforts to reduce the harvests to prevent overfishing would lead to severe economic suffering in the fishing communities. Pro-grams to conserve and improve cockle habitats may be the most judicious actions to take. Preserving the mangrove swamps intact, increasing their sizes where possible, and controlling cockle predators would lead to an increase in cockle abundance and harvests. Fishes that prey on juvenile cockles might be seined along the edges of swamps before the tide rises and they swim into the swamps to feed. Transplanting mangrove seedlings to suitable areas might increase the size of those habitats. The numbers of fishermen may increase in the future, because most adults now have several children. If new fishermen are tempted to harvest small, immature cockles and stocks are not increased, minimum size rules for harvestable cockles could be implemented and enforced to ensure adequate spawning.

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The National Marine Fisheries Service’s Alaska Fisheries Science Center (AFSC) has a long and successful history of conducting research in cooperation with the fishing industry. Many of the AFSC’s annual resource assessment surveys are carried out aboard chartered commercial vessels and the skill and experience of captains and crew are integral to the success of this work. Fishing companies have been contracted to provide vessels and expertise for many different types of research, including testing and evaluation of survey and commercial fishing gear and development of improved methods for estimating commercial catch quantity and composition. AFSC scientists have also participated in a number of industry-initiated research projects including development of selective fishing gears for bycatch reduction and evaluating and improving observer catch composition sampling. In this paper, we describe the legal and regulatory provisions for these types of cooperative work and present examples to illustrate the process and identify the requirements for successful cooperative research.

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Long-term trends in the abundance and distribution of several pinniped species and commercially important fisheries of New England and the contiguous U.S. west coast are reviewed, and their actual and potential interactions discussed. Emphasis is on biological interactions or competition. The pinnipeds include the western North Atlantic stock of harbor seals, Phoca vitulina concolor; western North Atlantic gray seals, Halochoerus grypus; the U.S. stock of California sea lions, Zalophus californianus californianus; the eastern stock of Steller sea lions, Eumetopias jubatus; and Pacific harbor seals, Phoca vitulina richardii. Fisheries included are those for Atlantic cod, Gadus morhua; silver hake, Merluccius bilinearis; Atlantic herring, Clupea harengus; the coastal stock of Pacific whiting, Merluccius productus; market squid, Loligo opalescens; northern anchovy, Engraulis mordax; Pacific her-ring, Clupea pallasi; and Pacific sardine, Sardinops sagax. Most of these pinniped populations have grown exponentially since passage of the U.S. Marine Mammal Protection Act in 1972. They exploit a broad prey assemblage that includes several commercially valuable species. Direct competition with fisheries is therefore possible, as is competition for the prey of commercially valuable fish. The expanding pinniped populations, fluctuations in commercial fish biomass, and level of exploitation by the fisheries may affect this potential for competition. Concerns over pinnipeds impacting fisheries (especially those with localized spawning stocks or at low biomass levels) are more prevalent than concerns over fisheries’ impacts on pinnipeds. This review provides a framework to further evaluate potential biological interactions between these pinniped populations and the commercial fisheries with which they occur.

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Kumataro Ito produced hundreds of beautiful color paintings of fishes and invertebrates during and after the 1907-10 Philippine Expeditin of the U.S. Bureau of Fisheries Steamer Albatross. The paintings are housed in the files of the Divisions of Fishes and Mollusks, United States National Museum of Natural History, and Smithsonian Institution Archives, Washington, D.C. Few of those paintings have been published in color, but many have been publishes in black and white. Two years after the expedition, Ito came to Washington, D.C., in 1912 for an extended period to render final paintings based on preliminary color sketches made during the expedition. He did not completly render all the sketches during his stay, probably because he was asked to produced a large number of black-and-white illustrations of Philippine fishes, and a few of North American fishes. Most of the black-and-white illustrations have been published. Few publications containing Ito's Philippine and North American illustrations have acknowledged him. The very little that is known about Ito's life is discussed, examples of his black-and-white and colored fish paintings are reproduced, and his previously unacknowledged illustrations in various publications are herein acknowledged. Another Japanese artist, Yasui, about whom almost nothing is known, joined the Albatross during Ito's second tour on board the ship. It appears, with few exceptions, that Yasui produced only preliminary color sketches of fishes, which, if rendered as final paintings, were done by Ito.

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The marine invertebrates of North America received little attention before the arrival of Louis Agassiz in 1846. Agassiz and his students, particularly Addison E. Verrill and Richard Rathbun, and Agassiz's colleague Spencer F. Baird, provided the concept and stimulus for expanded investigations. Baird's U.S. Commission of Fish and Fisheries (1871) provided a principal means, especially through the U.S. Fisheries Steamer Albatross (1882). Rathbun participated in the first and third Albatrossscientific cruises in 1883-84 and published the fist accounts of Albatross parasitic copepods. The first report of Albatross planktonic copepods was published in 1895 by Wilhelm Giesbrecht of the Naples Zoological Station. Other collections were sent to the Norwegian Georg Ossian Sars. The American Charles Branch Wilson eventually added planktonic copepods to his extensive published works on the parasitic copepods from the Albatross. The Albatross copepods from San Francisco Bay were reported upon by Calvin Olin Esterly in 1924. Henry Bryant Bigelow accompanied the last scientific cruise of the Albatross in 1920. Bigelow incorporated the 1920 copepods into his definitive study of the plankton of the Gulf of Maine. The late Otohiko Tanaka, in 1969, published two reviews of Albatross copepods. Albatross copepods will long be worked and reworked. This great ship and her shipmates were mutually inspiring, and they inspire us still.

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Over a century of fi shery and oceanographic research conducted along the Atlantic coast of the United States has resulted in many publications using unofficial, and therefore unclear, geographic names for certain study areas. Such improper usage, besides being unscholarly, has and can lead to identification problems for readers unfamiliar with the area. Even worse, the use of electronic data bases and search engines can provide incomplete or confusing references when improper wording is used. The two terms used improperly most often are “Middle Atlantic Bight” and “South Atlantic Bight.” In general, the term “Middle Atlantic Bight” usually refers to an imprecise coastal area off the middle Atlantic states of New York, New Jersey, Delaware, Maryland, and Virginia, and the term “South Atlantic Bight” refers to the area off the southeastern states of North Carolina, South Carolina, Georgia, and Florida’s east coast.

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Honduras has many communities of artisanal fishermen who land various species of crustaceans and mollusks, using hands, nets, traps, and free diving from shore and from dugout canoes. It also has industrial fisheries for spiny lobster, Panulirus argus; queen conch, Strombus gigas; and mainly pink shrimp, Penaeus notialis, using traps, scuba divers, and trawl nets.

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The Northeast Fisheries Science Center of NOAA's National Marine Fisheries Service has a long history of research on benthic invertebrates and habitats in support of the management of living marine resources. These studies began in the 1870's under Spencer F. Baird's guidance as part of an effort to characterize the Nation's fisheries and living marine resources and their ecological interactions. This century and a quarter of research has included many benthic invertebrate studies, including community characterizations, shellfish biology and culture, pathology, ecosystem energy budget modeling, habitat evaluations, assessments of human impacts, toxic chemical bioaccumulation in demersal food webs, habitat or endangered species management, benthic autecology, systematics (to define new species and species population boundaries), and other benthic studies. Here we review the scope of past and current studies as a background for strategic research planning and suggest areas for further research to support NOAA's goals of sustainable fisheries management, healthy coastal ecosystems, and protected species populations.

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In April 1990, the Steller sea lion, Eumetopias jubatus, was listed as threatened under the U.S. Endangered Species Act by emergency action. Competitive interactions with the billion-dollar Alaska commercial groundfish fisheries have been suggested as one of the possible contributing factors to the Steller sea lion population decline. Since the listing, fisheries managers have attempted to address the potential impacts of the groundfish fisheries on Steller sea lion recovery. In this paper, we review pertinent Federal legislation, biological information on the Steller sea lion decline, changes in the Alaska trawl fishery for walleye pollock, Theragra chalcogramma, since the late 1970's, andpossible interactions between fisheries and sea lions. Using three cases, we illustrate how the listing of Steller sea lions has affected Alaska groundfish fisheries through: I) actions taken at the time of listing designed to limit the potential for directhuman-related sea lion mortality, 2) actions addressing spatial and temporal separation of fisheries from sea lions, and 3) introduction of risk-adverse stock assessment methodologies and Steller sea lion conservation considerations directly in the annual quota-setting process. This discussion shows some of the ways that North Pacific groundfish resource managers have begun to explicitly consider the conservation ofmarine mammal and other nontarget species.

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Three surveys spanning 28 years were examined for changes in species caught by recreational fishermen from small boats (skiffs) and commercial passenger fishing vessels (CPFV's) in California's Monterey Bay region. As fishing effort increased, the catch of certain nearshore species of rockfish, Sebastes spp., declined. CPFV fishing was conducted farther from port and in deeper water to compensate for declining abundance while most skiffs remained in traditional areas close to port. The trend toward deeper water CPFV fishing has been interrupted only temporarily by increased availability of nearshore species. Life history characteristics of rockfish including residential behavior, variable recruitment, and natural longevity contribute to a vulnerability to localized overfishing for several species.

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Fishing was America's first industry, and turtling played an important role in the nation's developing fisheries. However, before the European settlers arrived in the New World, Native Americans had already developed spiritual and gastronomic relationships with sea turtles. There are indications that ancient Florida tribes had eaten sea turtles and then placed the skulls in burial mounds (Johnson, 1952).

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Siddeek et al. (1991) discussed very briefly some recent developments in Kuwait's shrimp fishery, including an important increase in landings of the main commercial species, Penaeus semisulcatus. This increase coincided with a marked fall in landings of the other important species, Metapenaeus affinis. They thought that these changes were caused by a reduction in effort combined with a more or less simultaneous favorable environmental change for P. semisulcatus and an unfavorable environmental change for M. affinis, but did not give any unequivocal evidence to support this conclusion. The results they reported are, nevertheless, very important and may be relevant to scientists and managers in other parts of the world.