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1.
The fisheries structure, fishing gear, fishing vessels and their ownership, landing sites and markets, as well as fisheries management and fishers’ participation were surveyed in three tropical islands: Pohnpei (Micronesia), Mafia (Tanzania), and Guimaras (Philippines), covering 127 fishers. Labour-intensive gear, including purse seines and ring nets, characterised Mafia fisheries. Fibre-reinforced plastic (FRP) boats characterised Pohnpei fisheries, and canoes with nonmarine engines were characteristic of Guimaras fisheries. Wooden plank boats with large crews were only seen in Mafia. From a gear/vessel ownership perspective, the fisher categories present were gear fishers, gear-vessel fishers, employers, and casual labour fishers. Casual labour fishers and employers were only apparent in Mafia. The fisheries in Pohnpei had a relatively early age of entry, which was attributed to the urban markets available and family cohesion, while community organisation-based management of these fisheries was weak. Mafia and rural Guimaras fishers depended on middlemen, due to the distance of the market. Deteriorating subsistence-related fishery dependency means that the Guimaras fishers’ community is at risk. The high shared gear/vessel ownership rates and levels of affiliation to community organisations in Mafia reflect government’s timely community sustainability enhancement initiative. Based on our analyses, we propose the “fishers’ community sustainability” concept. The sustainability of a fisher’s community can be judged on (1) the age of entry to the fisheries, (2) the monetary profits made at fish markets and through marketing, (3) the cohesion among the fishers, and (4) the level of subsistence-related dependency on the fishery. The fishery is key to community sustainability, thus ensuring fishery-dependent life. It is essential to consider the above indicators of fishers’ community sustainability during fisheries development.  相似文献   

2.
Ding  Qi  Shan  Xiujuan  Jin  Xianshi  Gorfine  Harry 《Fisheries Science》2021,87(3):297-309
Fisheries Science - China (herein referred as China’s mainland, and excluding Hong Kong, Macau and Taiwan) is the largest contributor to global seafood production. While China’s marine...  相似文献   

3.
Small‐scale driftnets (SSDs) have been historically used in the Mediterranean without major environmental concern. The introduction of large‐scale driftnets caused unwanted catches of protected species. Specific regulations were therefore issued in European waters, culminating in a proposed moratorium on SSDs. This study aimed to characterise the SSD fishery targeting anchovy (menaide), evaluating its environmental sustainability, economic performance and social relevance. In 2013, a survey by interviews, logbooks and observers on board assessed the order of magnitude of this fishery in terms of fishing capacity and activity, volume of landings and revenues. The menaide fleet consisted in 60 vessels <12 m overall length, moored in little harbours in southern Italy. These nets are highly selective: the target species, European anchovy, Engraulis encrasicholus (L.) and sardine, Sardina pilchardus (Walbaum), dominates the catches, while discards are negligible. The anchovies caught are of high quality and large size; the high prices support fish processing by local factories. Moreover, the results of a SWOT analysis demonstrated that replacing SSDs with a semi‐industrial fishery, like purse seining, would increase impacts on the ecosystem, and a loss of socio‐economic opportunities for several coastal villages. These findings support the option of keeping SSDs operating, in the framework of specifically oriented management measures.  相似文献   

4.
Many adult sea bass (>40 cm total length) tagged between May and October around the coasts of England and Wales have been recaptured close to their respective tagging locations in successive years. Analysis of mark and recapture data sets, for the late 1970s and early 1980s and in 2000–2006, show that some 55% of all recaptures were within 16 km of their original release position. This suggests that mortality rates of adult bass in local populations could be reduced by around 50% if a number of carefully selected areas were designated as catch and release only for bass, thus providing a management option with which more and bigger sea bass will be available to recreational sea anglers.  相似文献   

5.
Aquaculture International - Pacific white shrimp (Penaeus vannamei) farming is an important commercial aquaculture production system contributing substantially to the economic and societal...  相似文献   

6.
This study represents the first quantitative analysis of the characteristics of the distribution areas and stomach contents of common minke whale Balaenoptera acutorostrata, sei whale B. borealis, and Bryde’s whale B. edeni in relation to oceanographic and prey environments in mid summer in the western North Pacific. Common minke whales were distributed within subarctic regions and the northernmost region of the transitional domain, coinciding with the main habitat of their preferred prey, Pacific saury Cololabis saira. Sei whales were mainly found in the northernmost part of the transition zone and showed prey preference for Japanese anchovy Engraulis japonica, which was significantly more abundant in the main distribution area of the whale than in its adjacent areas. “Hot spots” of Bryde’s whales were found in several regions of the transition zone between the subarctic boundary and the Kuroshio front. This whale species preferred Japanese anchovy as prey, for which the distribution density was significantly higher in the main distribution area of the whale than in the adjacent areas. These results indicate that the summer distributions of Pacific saury and Japanese anchovy greatly influence the distributions of these whale species, suggesting that the whales’ habitat selection is closely related to their prey selection.  相似文献   

7.
Fisheries policies often pursue multiple objectives, which may, in some instances, be in conflict or competition with each other. It may not be possible, for example, to create or maintain employment and generate increasing volumes of revenue for government whilst also sustaining stocks and biodiversity. Two approaches to fisheries management, one focused on capturing wealth and limiting access and the other on maintaining access for employment and providing community development and welfare, present contrasting policy advice, with different points of emphases and objectives. This article examines the case of Lake Victoria, where the three main commercial fisheries are seen to contribute to different objectives for the lake's fisheries. Insights from the debate between wealth‐based and welfare‐based approaches to fisheries management provide a framework for the analysis of fisheries policy and practice on the lake. From the analysis, it is concluded that whilst there is much rhetoric in support of a wealth‐based approach, this has not been followed through in implementation, reflecting the lack of political support for new taxation and limiting access. The welfare functions of the fisheries are significant, but could be substantially strengthened through greater investment in the provision of services to fisheries communities. The approaches are not mutually exclusive, but pursuing wealth‐based management must support livelihoods, employment and development, as well as fisheries management objectives. Without the incorporation of welfare objectives, fisheries policies will not be politically accepted or fully implemented, suggesting the need for a balance between wealth and welfare objectives and measures.  相似文献   

8.
Cryptocaryon irritans Brown 1951, a holotrichous ciliate parasite of marine fishes, causes marine white spot disease. In aquaria, C. irritans can cause acute damage and heavy mortalities to marine teleosts. Although first described 60 years ago, only within the last decade has detailed information emerged concerning its life cycle, transmission and pathogenesis. An update of our knowledge of this important aquarium fish parasite is presented here.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   

9.
An introduced pathogenic fish trematode, Parabucephalopsis parasiluri Wang, 1985 (Digenea: Bucephalidae), was studied to determine the seasonal fluctuation in its metacercariae abundance. The timing of the recruitment period of the metacercariae and the relationship between yearly fluctuation in metacercarial abundance and some environmental factors were also examined to develop an effective plan for disease control. Monthly changes in metacercarial abundance in the caudal fin of pale chub (Zacco platypus) and of the prevalence of the first intermediate host (golden mussel Limnoperna fortunei) suggest that P. parasiluri generally has an annual life cycle. The metacercarial abundance in chub increased when the water temperature fell below 7°C in winter, but the rapidity of the increase varied between 2007 and 2008. The fluctuations in the abundance of metacercariae in winter from 2001 to 2008 showed that mean flow rate and mean water level in January were negatively related to the infection level each year, and positively related to the mean water temperature. Based on these results, we propose a control plan for parabucephalopsiosis involving discharge control; that is, more than 50 m3/s (corresponding to 150 m3/s in the Yodo River) of water should be flushed from upstream dams for a period of at least one week starting on the day when the water temperature falls below 7°C.  相似文献   

10.
11.
We have modeled the prey–predator dynamics between nutrients, phytoplankton, and copepods in Hiuchi-nada, central part of the Seto Inland Sea. The model parameters were estimated by stepwise regression using data sampled from 2001 to 2005. We re-created the fluctuations in copepod biomass in the spring–summer of 2001–2004 by model simulation and investigated the relationship between the re-created copepod biomass and anchovy Engraulis japonicus reproductive success rate in Hiuchi-nada. The anchovy reproductive success rate was proportional to the copepod biomass during the last 10 days of May, a period that immediately preceded anchovy recruitment. This relationship indicates that a possible key factor in the regulation of anchovy population levels is the fluctuation in abundance of the copepod assemblage and that the crucial period for anchovy recruitment in Hiuchi-nada would be the period just before anchovy recruitment to the shirasu (body length: approx. 20–35 mm) fishery. These results provide a potential framework for forecasting the anchovy recruitment level that is based on both larval abundance and survival rate as estimated from the biomass of copepods in the pre-recruitment period of anchovy.  相似文献   

12.
The culture of the Eastern oyster (Crassostrea virginica) in containment gear has become a viable component of restoration programs in many states on the East Coast of the United States, and it has been suggested that these operations may provide many of the same ecological services as natural or restored reefs. Our two-part study comparing the diversity and abundance in macro-epifaunal communities associated with a sub-tidal-created oyster reef and ‘modified rack and bag’ cage system (Part I) and floating oyster cages for restoration (Part II) occurred over the summer and fall of 2006 and 2007, respectively. In Part I, a greater total abundance and species richness (P < 0.05) was found to be associated with the cages, but greater evenness (P < 0.05) was found on the reef. No significant difference (P > 0.05) was found in species diversity according to Simpson’s index by habitat type, but it was significant (P < 0.05) by month. These samples were dominated by naked goby (Gobisoma bosc) and Atlantic mud crab (Panopeus herbstii). Spaghetti worm (Ampharetidae, P < 0.01), sheepshead (Archosargus probatocephalus, P < 0.01), blue crab (Callinectes sapidus, P < 0.01), grey snapper (Lutjanus griseus, P < 0.05), gag grouper (Mycteroperca microlepis, P < 0.01), and Atlantic oyster drill (Urosalpinx cinera, P < 0.05) were unique to the cages, while the skilletfish (Gobiesox strumosus) was unique to the reef. Part II revealed that the floating cages supported 13 species of fish and invertebrates, although no significant differences in species richness, evenness, or diversity were found by month or by bay area (P > 0.05). These results suggest that created reefs in conjunction with ‘rack and bag’ cage systems, as well as floating cage systems, support ecologically and economically important macro-epifauna, even at very small scales.  相似文献   

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