2,873 research outputs found
Distribution of heavy metals in the northern shrimp Pandalus borealis from the Oslofjord
Studies on the distribution of heavy metals like copper, cadmium, zinc, lead and mercury in deep sea prawns Pandalus borealis in the Oslofjord region showed that those collected from inner and middle fjord contained higher levels of heavy metals than those from the outer fjord. Their content in the edible portions, viz., tail muscle, was less compared to other organs. In terms of metal concentration copper and zinc are present in significant quantities in Pandalus borealis
Synopsis of biological data on the pink shrimp, Pandalus borealis Kroyer, 1838
This synopsis of the literature was designed to summarize the biological and biochemical studies involving Pandalus borealis as well as to provide a summary of the literature regarding the fisheries data published before early 1984. Included are many unpublished observations, drawn from studies at the State of Maine Department of Marine Resources Laboratory in West Boothbay Harbor, Maine. (PDF file contains 63 pages.
Stock assessment in brown shrimp (Crangon crangon) part 1: Investigation of possible methods
Het Ministerie van LNV, de gezamenlijke Producentenorganisaties voor de garnalenvisserij in Nederland, en de natuurorganisaties Stichting de Noordzee en de Waddenvereniging hebben het belang onderschreven van een gezamenlijk traject naar een verduurzaming van de garnalenvisserij en het verkrijgen van een MSC (Marine Stewardship Councel) certificering voor de garnalenvisserij. Om voor een MSC label in aanmerking te komen moet er aangetoond worden dat de gewone garnaal, Crangon crangon, niet overbevist wordt. Momenteel wordt de garnalen visserij niet beheerd en is er geen officiële bestandschatting. Wel worden er door de ICES crangon werkgroep (WGCRAN, ICES working Group on crangon fisheries and life history) op een beschrijvende manier de fluctuaties in dichtheden van de gewone garnaal bijgehouden. Het is echter wenselijk om tot een meer kwantitatieve bestandschatting te komen
Effects of temperature on the biology of the northern shrimp, Pandalus borealis, in the Gulf of Maine
Length-frequency data collected from inshore and offshore locations in the Gulf of Maine in 1966-1968 indicated that ovigerous female northern shrimp (Pandalus borealis) first appeared offshore in August and September and migrated
inshore in the fall and winter. Once eggs hatched, surviving females returned offshore. Juveniles and males migrated offshore during their first two years of life. Sex transition occurred in both inshore and oll'shore waters, but most males changed sex offshore during their third and fourth years. Most shrimp changed sex and matured as females for the first time in their fourth year. Smaller females and females exposed to colder bottom temperatures spawned first. The incidence of egg parasitism peaked in January and was higher for shrimp exposed to warmer bottom temperatures. Accelerated growth at higher temperatures appeared to result in earlier or more rapid sex transition. Males and non-ovigerous females were observed to make diurnal vertical migrations, but were not found in near-
surface waters where the temperature exceeded 6°C. Ovigerous females fed more heavily on benthic molluscs in inshore waters in the winter, presumably because the egg masses they were carrying prevented them from migrating vertically at night.
Northern shrimp were more abundant in the southwestern region of the Gulf of Maine where bottom temperatures remain low throughout the year. Bottom trawl catch rates were highest in Jeffreys Basin where bottom temperatures were lower than at any other sampling location. Catch rates throughout the study area were inversely related to bottom temperature and reached a maximum at 3°C.
An increase of 40% in fecundity between 1973 and 1979 was associated with a decline of 2-3°C in April-July offshore bottom temperatures. Furthermore, a decrease in mean fecundity per 25 mm female between 1965 and 1970 was linearly related to reduced landings between 1969 and 1974. It is hypothesized that temperature-induced changes in fecundity and, possibly, in the extent of egg mortality
due to parasitism, may provide a mechanism which could partially account for changes in the size of the Gulf of Maine northern shrimp population during the last thirty years. (PDF file contains 28 pages.
West Greenland\u27s Cod-to-Shrimp Transition: Local Dimensions of Climatic Change
Abstract
West Greenland\u27s transition from a cod-fishing to a shrimp-fishing economy, ca. 1960-90, provides a case study in the human dimensions of climatic change. Physical, biological, and social systems interacted in complex ways to affect coastal communities. For this integrated case study, we examine linkages between atmospheric conditions (including the North Atlantic Oscillation), ocean circulation, ecosystem conditions, fishery activities, and the livelihoods and population changes of two West Greenland towns: Sisimiut, south of Disko Bay, and Paamiut, on the southwest coast. Sisimiut prospered as a fishing center through the cod-to-shrimp transition. Paamiut, more specialized in cod fishing, declined. Their stories suggest two general propositions about the human dimensions of climatic change. First, socially important environmental changes result not simply from climatic change, but from interactions between climate, ecosystem, and resource usage. Second, environmental changes affect people differentially and through interactions with social factors. Social networks and cohesion (social capital) are important, in addition to skills (human capital), investments (physical capital), and alternative resources (natural capital): all shape how the benefits and costs are distributed
Food and Feeding of Most Abundant Fish Species in Flemish Cap
Food and feeding of the 15 fish species taken by bottom trawl from Flemish Cap Bank in summer during the period 2001-2003 were analysed. The stomach contents of 17 773 fish were collected in depths from 83 to 730 m. In general, the feeding intensity was high in all the species with a maximum value for Gadus morhua (96.3%) and minimum for Lycodes reticulatus (35.0%). The prey spectrum was width, with a total of 134 items for all the stomachs analysed. In frequency of occurrence, the crustaceans were the most important preys (FO = 80.4%), while in volume (V = 39.4%) they were less
significant than fishes (V = 43.5%). The main prey group in frequency of occurrence were Hyperiidea, Copepoda, Pandalus borealis and Chaetognata.
The niche width index was also calculated for these species
Northern Shrimp (Pandalus borealis, Krøyer) in Spanish Bottom Trawl Survey 2004 and 2005 in NAFO Divisions 3LNO
The results of northern shrimp (Pandalus borealis) obtained from the Spanish bottom trawl surveys in the NAFO Regulatory Area (Divisions 3NO) in spring-summer 2004 and 2005, carried out by the Instituto Español de OceanografĂa (Spanish Oceanographic Institute, Vigo Centre), are presented and compared with those from previous surveys from the same series. The catches 550 and 368 kg obtained in 2004 and 2005, respectively, confirmed the increase of shrimp importance in the last years in the Div. 3NO with an estimated biomass by swept area method around 2000 tons. Catch results from the surveys and data analysis are discussed in this paper
Historic landings of northern shrimp (Pandalus borealis) in Norway - Data per county for 1908-2021
Time series of landed catches are often the only data source available that encompasses most or all of a fishery’s history, providing important information for stock assessment and fisheries management. Although landings data were registered in Norway with a spatial resolution of landing county or lower for over a century, most of the data were only published in statistical yearbooks in the past and are therefore not readily available. Here, we digitalized spatially resolved information on shrimp landings and value of landings from 1908 to 1976, and combined them with landings data from 1977 to 2021 to produce a comprehensive overview of the shrimp fishery in Norway since its infancy more than a century ago until today. The resulting time series shows how the shrimp fishery after its beginning in the eastern Skagerrak and Oslofjord region at the turn of the 20th century, expanded west- and northwards along the Norwegian coast over the following decades, developing into a relevant coastal fishery as well as an offshore fishery in the Skagerrak. After World War II had temporarily halted the development of the fishery, it increased with a higher pace due to subsequent progress in industrial fishing and the emergence of offshore fisheries in the Barents Sea and around Svalbard. The latter development caused together with periods of long-distance fishing activities in the Northwest-Atlantic and around Greenland and Jan Mayen substantial increases in shrimp landings from the 1980s onwards. While total annual shrimp landings remained largely on the level of a few thousand tonnes in previous decades, they peaked above 80 000 tonnes in the 1980s and early 2000s. However, throughout the time series and particularly during the latest decades, substantial fluctuations in landings and their spatial distribution have been observed. In absence of catch limits for shrimp outside of the Norwegian Deep and Skagerrak area, the observed changes in the landings have mostly been driven by technological progress and economic factors, notably prices. However, masked by the large landings from the offshore segments of the fishery, the data also show a decline of shrimp landings in West- and Mid-Norway, indicating a disappearance of the shrimp fishery and possibly also the shrimp stock in these areas. The results underline the relevance of spatially resolved landings and value data for our understanding of the development of a fishery across its history, and thus the importance of making such data readily available to research and fisheries management.Historic landings of northern shrimp (Pandalus borealis) in Norway - Data per county for 1908-2021publishedVersio
Northern Shrimp (Pandalus borealis, Krøyer) in Spanish Bottom Trawl Survey 2003 in NAFO Divisions 3LNO
The results on northern shrimp (Pandalus borealis) obtained from a Spanish bottom trawl survey in the NAFO
Regulatory Area (Divisions 3NO) in spring 2003, carried out by the Instituto Español de OceanografĂa (Spanish
Oceanographic Institute, Vigo Centre), are presented and compared with those from previous surveys from the same
series. Catch obtained (324.8 kg.) is the second highest in the series, thus maintaining the catch increase noted in
2002 (total of 408.1 kg.) relative to previous years.
For the first time, the IEO has enlarged the sampling area to Div. 3L, where important shrimp catches were obtained
(5835.8 kg.).
Catch results from the surveys and data analysis are discussed in this paper
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