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1.
In the Northeast Atlantic, elasmobranchs are a common bycatch in many fisheries, including demersal trawls, longlines, or gillnets and many countries do not have regulations or any control over the amount taken. In the Mid Atlantic, the Azores EEZ (Exclusive Economic Zone), small-scale fishing operations, artisanal and hook-and-line fishing methods are responsible for part of local total landed elasmobranch biomass, although some species are specifically focused and severely harvested by international large-scale fleets. This work provides a review and analysis of the commercial elasmobranch fisheries in the Azores EEZ, and its evolution over the last two decades, highlighting management priorities, taking into account the Northeast Atlantic elasmobranch fisheries status. In the Mid-Atlantic, elasmobranch fisheries mainly target 4 species, that are usually landed as bycatch: the tope shark (Galeorhinus galeus) and the thornback ray (Raja clavata), captured mainly by local demersal artisanal fisheries, the blue shark (Prionace glauca) and the shortfin mako shark (Isurus oxyrinchus) captured by a more industrialised fleet, including those from foreign nations. Considering elasmobranchs life history traits and fishery history, caution is advised in the development of a management strategy focusing on these species, considering the Northeast Atlantic context and regional, local and national interests.  相似文献   

2.
Climate change affects ocean conditions, fish stocks and hence fisheries. In West Africa, climate change impacts on fisheries were projected to be mainly negative through multi-facet ways. However, analysis of adaptation responses of fishers to climate change impacts is scarce. This paper reviews the impacts on climate change on fisheries in West Africa and discusses the potential adaptation strategies adopted by both the artisanal and industrial fishing sectors. Overall, climate change and over-exploitation have altered species composition of fisheries catches in West Africa. The effect of ocean warming on fisheries is indicated by the increase in dominance of warmer water species in the landings, shown from an increase in Mean Temperature of Catch, in the region. Climate change induced changes in potential catch and species composition, which inherently have similar symptoms as over-exploitation, are expected to have repercussions on the economic and social performance of fisheries. Both artisanal and industrial sectors may adapt to these changes mainly through expansion of fishing ground that increases operation costs. Our results highlight that historical changes in target species are more common in industrial than artisanal fisheries. This result challenges the prevailing assumption that artisanal fisheries, given their limited movement capacity, would adapt to climate change by shifting target species and/or gear type.  相似文献   

3.
Decline in tuna fish stocks due to weak enforcement of regulations on fishing effort poses a challenge to the sustainability of tuna fishery. Intervention programs to address this problem require an understanding of the operational behaviour of the fishers and how various socioeconomic factors may impact fishers’ decisions to continue or discontinue their fishing efforts. A semi-structured interview questionnaire was developed to find whether fishers are willing to keep, change their fishing strategies or exit the fishery if their regular catch will decline by half. Boat captains, assistant boat captains and crew from General Santos City, Lupon, Mati City and Governor Generoso in the Philippines (n=293) were purposively selected for interviews. Results show that fishers from General Santos City with ancillary industries and Lupon with fewer economic development are more willing to adapt or change their fishing strategies. The catch value or price was found to have a strong influence on the likelihood that anchored FAD tuna fishers will adapt or change their fishing strategy when their catches decline. Fishers whose catch fetched a price of PhP 151.00 (US$ 3.48) and above Php 200 (US$ 4.61) have 80% probability to change their fishing strategy. The proportion of catch sold also had a high influence on the decisions to adapt in the fishery with fishers selling 36% and 73% of their catches have 100% and 70% probability to adapt. The results suggest a reluctance to exit the fisheries even when tuna fishing is no longer economically viable, fishers opt to adapt.  相似文献   

4.
Data collected by questionnaire and telephone surveys conducted during 1998 and 1999 are used to describe the socio-economic characteristics of inshore netfishers in the Western Cape. Approximately two-thirds of netfishers work or have worked in other fishing sectors and a further 6–50%, depending on the area surveyed, are retired. Very few (0–11%) permit-holders in most areas classified their occupations as netfishers and the majority claimed to make <5% of their income from netfishing. Estimated costs and returns to net permit-holders suggest that, in most areas, commercial netfishing at current levels of catch and effort is not economically sustainable in the long-term. Only Saldanha-Langebaan gillnetters and beach-seine permit-holders, on average, manage to cover their opportunity costs and make an economic profit. The lack of profits in other areas is compelling evidence that the net fisheries are at or beyond the open access equilibrium point, suggesting that effort reduction in the order of 60% is necessary if maximum economic yield is to be obtained from the fishery. The netfisheries provide part-time employment for approximately 2 000 crew in the Western Cape. Additional economic benefits and employment directly related to the fishery in the form of equipment and fuel purchases made by fishers, maintenance of fishing gear and the sale of fish are estimated to contribute at least R15 million to the regional economy annually. Between 42 and 76% of respondents felt that their catches had declined since they had started netfishing and most felt that no new permits should be issued. Knowledge of catch restrictions among respondents was low (53–73%), indicative of a lack of communication between management and fishers, poorly defined permit conditions and a lack of enforcement. Many fishers interviewed feel it is unfair that they are restricted to catching only low-value target species and do not adhere to the catch restrictions, even if they do know them. The importance of the netfishery for participants varies greatly between and within areas. In order to reduce effort equitably, current and potential new permit-holders should be assessed on an individual merit basis.  相似文献   

5.
In Piriápolis (Uruguay) and Paraty (Brazil), artisanal fishers view fishing as a way of life, rather than just a job. The freedom of fishing and an inherent satisfaction in the occupation figure large in fishers' attachment to it. There are strong indications, however, that the relationship of fishers to fishing is changing. First, while fishers from both areas wish to keep fishing in the future, they are moving into different occupations or supplementing their work in fishing with other employment. Second, artisanal fishers from Piriápolis and Paraty identified fishing as an undesirable occupation for their children because they believe that in the future fishing will no longer be a viable occupation. Nonetheless, despite the wishes of their parents, young men and women in Piriápolis and to a much lesser degree in Paraty continue to become involved in fishing and fishing-related activities. The paper uses a social wellbeing perspective to interpret fisher responses to the changing circumstances they face. Wellbeing is a lens to understand the distinctive features of artisanal fisheries and helps to understand fishers' disenchantment with fisheries governance processes, in a scenario where participation is being promoted by the state in Uruguay and Brazil. The implications of these findings for state efforts to promote fisher participation in governance are discussed.  相似文献   

6.
Identifying socio-economic drivers of small-scale fisheries is a fundamental step to understand impacts and pressures on fishery resources, and the behaviour of seafood trade actors. It is especially relevant for developing countries where such information is usually lacking and fisheries management is greatly needed. To address this gap, this study maps the structure of value chains of fish and marine invertebrates caught by small-scale fisheries from São Vicente, Cape Verde (West Africa), and examines the main socio-economic drivers behind the seafood trade on the island. Specifically, it shows how drivers, such as tourism and the local market, shape the preferences for certain species and how they affect the distribution of income among actors involved in the seafood trade. To collect this information, interviews were done with fishers, small-scale traders, market vendors, and restaurant owners, in all fishing communities of the island of São Vicente, in 2015. Tourism and the local market drive the exploitation of a wide variety of marine species, from small demersal low trophic level fish and marine invertebrates, to large pelagic high trophic level fish species. Moreover, the local seafood market, and especially tourism dynamics, contribute to the unequal distribution of income among actor groups, benefiting mostly restaurant owners due to their direct access to tourist consumers. Such findings have implications for local fishery resources management, food security, and fishing communities’ livelihoods.  相似文献   

7.
Coral reef fish are an important source of food security and income for human coastal populations. They also underpin ecosystem processes vital for the future ability of coral reefs to generate ecological goods and services. Identifying socio-economic drivers behind the exploitation of fish that uphold these key ecosystem processes and the scales at which they operate is therefore critical for successful management. This study addresses this issue by examining the reef-associated fish value chain in Zanzibar, and how it links to functional groups of fish and maturity stage of fish within these groups. Semi-structured interviews with 188 respondents (fishers, traders and hotel staff) involved in the fisheries and trade with reef-associated fish in Zanzibar and participatory observations were used. The trade with reef fish in Zanzibar is a complex structure involving many different agents and this study shows that these different agents exhibit differential “preferences” regarding fish functional groups and/or maturity stages within these groups. Consequently, both high and low trophic species, as well as small and large fishes are fished and sold, which leaves no refuge for the fish assemblage to escape fishing. When other market agents than fishers have so much influence and there are few alternative income generating activities, it is not possible to put all burden on fishers. Management measures that extend down the value chain to include all market agents as well as their links to ecosystem processes are thus likely to be needed to reach the target of sustainable fisheries.  相似文献   

8.
Small pelagics are the main fish resource in North West Africa. In Senegal, these are mainly sardinellas (Sardinella aurita and S. maderensis) and bonga shad (Ethmalosa fimbriata). The fisheries, mainly encircling gillnets and purse seines, are predominantly performed by artisanal fishers and are of great importance for the Senegalese economy and for food security in the region. However, in recent years, the main conditions for these fisheries have changed and recent observations have shown strong declines in profit. An analysis over the last twenty years (1993–2013) show that the fisheries lost profit between 65% and 100% while operating costs increased by 25% and 90%, for encircling gillnet and purse seine, respectively. While the fuel price dominates as determining factor during the survey period, important other drivers during the last five years were a decrease in fish biomass and an increase in fishing effort.  相似文献   

9.
10.
Artisanal fisheries throughout the Mediterranean region are managed mostly by applying gear specific regulations. The data about the extent and dynamics by which littoral fish resources respond to commonly proposed changes of such regulations are lacking. Here the results of a 15 year (1995–2009) monitoring programme of littoral fish resources in a pilot region of island Vis aquatorium, central Adriatic Sea, are reported with the scope of investigating whether a more restrictive fishing regime (encompassing an increase in minimum inner layer mesh size of trammel net from 28 to 40 mm and excluding the trammel net from subsistence artisanal fishing) that has progressively been put in place during the study period has been accompanied by expected positive changes of littoral fish resources’ abundance, biomass and structure. Significant increases over time were observed in most of the community indices analyzed (abundance and biomass catch per unit effort, diversity indices) as well as a directional change in abundance and biomass catch composition of littoral fish resources. Positive responses were, however, primarily related with a recovery of Mullus surmuletus stock. Additionally, time-series analysis of ABC curves and their corresponding W index revealed that fish community in the study area was still moderately disturbed. Limited extent of conventional management restorative potential is further exacerbated by social issues – noncompliant behavior mainly among subsistence artisanal fishers and consequent resentment of commercial artisanal fishers. In order to improve further the state of the resources a more comprehensive set of management measures incorporating closed areas and a new approach actively involving fishers in the management process should be adopted.  相似文献   

11.
To develop a management strategy for informal fishers, a necessary first step is information about the nature of these fishers, their numbers and their socio-economic status. To accomplish this, a survey of socio-economic conditions and use of marine resources was undertaken in 1999 at 20 localities where fishing occurs around the coast of South Africa, concentrating on subsistence or small- to micro-scale artisanal commercial fishers. In each locality, 16–31 "fisher households" were surveyed by questionnaires, focus-group discussions and interviews with key informants. Demographic analyses revealed a low level of migrancy (~5%), an average of 5.3 persons per household and a mean age of 27. Only ~20% of fishers were women and ~15% were children. Poverty was prevalent: unemployment averaged 40.3% (much higher than the national norm of 29.3%). Mean adult equivalent income per month spanned R193–R735 among regions, and was not correlated with size of settlement. Education levels were low, only ~33% of people >20 years old having completed primary school. Migrancy was highest in rural areas (but still much less than the national norm), intermediate in towns and least in metropolitan areas. Household size, participation of women and poverty all followed similar trends. Comparing regions, the East Coast and the province of KwaZulu-Natal had higher migrancy rates, larger household sizes, greater poverty, and greater participation by women in fishing, than on the South and West coasts. Household expenditure on food was ~R450 per month on the South-East and KwaZulu-Natal coasts and ~R750 on the West Coast, and exceeded 60% of income (a measure of "food security") in about half the households surveyed. Harvested resources were sold, consumed or used as bait. In all regions, the two most frequently harvested resources were fish (mostly sold, predominantly fished by men) and intertidal rocky-shore invertebrates (largely consumed, and involving women to a greater degree). On the West Coast, rock lobster Jasus lalandii was the third-most important resource, but on the South and KwaZulu-Natal coasts this species was replaced by estuarine invertebrates. Abalone Haliotis midae, oysters, sandy-beach invertebrates and kelp or seaweeds made up the balance. Diversity of harvested resources increased west to east, following biogeographic trends. The resources could be divided into those of high value (rock lobsters, abalone and, to a lesser extent, fish) and those of lower value (such as limpets, mussels and bait organisms). It is argued that high-value resources are best used to create micro- and small-scale commercial enterprises that can serve to uplift poor fishers. Low-value resources constitute subsistence resources, for which preferential rights should be established for subsistence fishers, including development of exclusive-use zones where necessary. Emerging characteristics of fishing communities that were helpful in defining subsistence fishers in the South African context were poverty, harvest for self-use (whether by consumption or sale to meet basic needs of food security), use of low-technology gear, and concentration of effort on or from shores or in estuaries. At least portions of the catches of all resources are sold, and the majority of equipment is purchased, so any definition of subsistence fishers cannot exclude those who sell part of their catch or do not use hand-made equipment. Some success was evident with co-management, encouraging further exploration of this style of management for subsistence fishers.  相似文献   

12.
The sparid Dentex macrophthalmus is a widespread, important fishery species along most of the West African coast from southern Namibia to the Mediterranean. In southern Angola it is an important artisanal species targeted predominantly by handline fishers. A biological and fisheries study was conducted on this species in southern Angola between June 2008 and July 2009. It was the dominant species in the artisanal fishery, accounting for 99% of the sparids captured and 67% (by mass) of the total catch. The life history of D. macrophthalmus was characterised by slow growth (females: Lt = 309[1 ? e?0.06(t + 5.43)], males: Lt = 248[1 ? e?0.16(t ? 1.77)]), advanced age at maturity (females: 7.4 years, males: 6.0 years) and high longevity (females: 36 years, males: 38 years). The sex ratio was 1:1 male:female. The length- and age-frequency distributions and macroscopic observations suggested that the species is a late gonochorist. Males and females reached 50% maturity at 151 and 166 mm fork length respectively. Although individuals with ripe gonads were found during most of the year, the peak spawning period appeared to be in December and January. Despite a life history that renders D. macrophthal-mus vulnerable to overexploitation, only 38% of artisanal fishers noticed a decline in the catches of this species. Potential reasons for this include: technology creep; limited pressure on the juvenile portion of the stock as a result of late recruitment (above the length of 50% maturity); the ‘basin affect’, whereby depleted areas are reseeded by areas (e.g. deeper water) inaccessible to the linefishery; and a deep-water reserve of large individuals. It is recommended that precautionary management strategies be implemented until the age estimates are revised by the countries in which this species forms significant fisheries.  相似文献   

13.
To understand small-scale fisheries in Mexico, the spatial and temporal distribution of the landed catch of several species was analyzed, including abalone, clams, snails, octopus, squids, lobsters, shrimps, blue crabs, sharks, rays and finfish along the 349 km of the Gulf of Ulloa coast. Data reported by fishers from 1998 to 2009 on catch volume and value per group of species and per fishing locality, together with the number of landing events, were used to define fishing zones and the relative importance of each fishery. Finfish turned out the primary fishery in the region, but the other fisheries showed relevant spatial changes that should be considered when establishing management goals and fishing regulations according to resource availability, fleet efficiency, processing capacity, commercialization of fishing products and profit distribution.  相似文献   

14.
This study, carried out in five fishing communities along the Kenyan coast, examined fisheries-derived income of fishers and traders in two different invertebrate fisheries (octopus and sea cucumber) and tested if differences in global market integration of these two products could explain differences in income inequalities among actors involved in the two fisheries. The structure of the value chains was mapped, differences in income between fishers and traders tested, and income inequalities among actors in each fishery examined. Although the octopus fishery included a greater diversity of actors and thereby provides income to a larger group of people, income inequality in this fishery was higher among fishers and traders than in the sea cucumber fishery. Thus, the often cited relationship between increasing market integration and income inequality may require a re-evaluation and a more nuanced treatment.  相似文献   

15.
Effective management of artisanal fisheries requires understanding fishers, their behaviors, and the drivers that underpin their choices. Behavioral drivers are critical links in understanding the interactions between social and ecological systems and can help inform effective management approaches. A Bayesian Belief Network modeling approach was used to investigate a diverse range of qualitative and quantitative social and ecological drivers of spatial location choice in a multi-species artisanal dive fishery in Costa Rica. Empirical and observer data used to populate the BBN showed the influence of economic factors, environmental conditions as well as social interactions on the decision-making process of spatial location choice. Good governance scenarios represented by Responsible Fisheries Marine Areas Management were analyzed for both hookah and free diving methods to assess the effects of responsible fishing on the fishers and the fishery. Model based-scenario analysis suggests that management interventions should consider the fisher's potential behavioral responses in the context of environmental variability, dependence on cultural assets, and food security. The results show that there is a need to understand fisher's decisions based on broad socio-ecological system understanding and consider the environmental outcomes alongside food security and the cultural significance of different marine species to fishing communities.  相似文献   

16.
This study investigates whether there has been a decline in fish stocks of a coral reef in Thailand, and if so, whether that decline is due to small-scale fishing. The research methods used included fish sampling by UVC, interviews and questionnaires with key informants and artisanal fishers. The results confirmed that there has been a decline in piscivores and carnivores (though not herbivores), and the main perceived threat came not from artisanal but from commercial fishing. Recommendations are to replace the largely unrestricted fishery with a more regulated regime backed by effective enforcement.  相似文献   

17.
The annual catch entitlement (ACE) scheme was added to New Zealand's quota management system for fisheries in 2001. The scheme allocates quota owners an annual share of the total allowable commercial catch (TACC) in proportion to their quota holding of a particular fishstock. With ACE being transferable, the change made it simpler for fishers (permit holders) who did not own quota to purchase ACE to match catch for specific fishstocks. But to be viable, non-quota-owning (ACE reliant) fishers need access to a reliable, long-term supply of ACE. This study examines the relationships between ACE reliant purchasers and their suppliers of ACE in New Zealand's Fishing Management Area Three during the 2014-15 fishing year. The study found that most buyers and sellers of ACE form enduring relationships to their mutual benefit. This symbiotic relationship bodes well for the survival of small fishers with the expertise to land fish in an efficient manner.  相似文献   

18.
A Dutch pilot study of fully documented fisheries provided the opportunity to observe actual changes in fishing behaviour under catch quota management (CQM). Interviews with fishers in the pilot study aided in interpreting the results and giving insight in the decision making process and reasoning of fishers. The CQM pilot study entailed a fleet of small and large demersal vessels. For these vessels, all cod catches were counted against quota, including catches of individuals below minimum landings size. To obtain reliable catch data all vessels were equipped with electronic monitoring (EM) systems. These systems recorded videos of all fishing and processing activities on board. In return, fishers received a 30% quota bonus for cod and were compensated with more flexibility on effort regulations. It was hypothesized that vessels in the CQM will (i) increase their landings by 30% according to their quota bonus, (ii) increase the use of gear with large mesh size, and (iii) change effort towards fishing locations with high catch rates of large cod and avoid areas with high catch rates of undersized cod. The results showed that CQM had no effect on fishing behaviour of the small vessels. In contrast, large vessels significantly increased their cod landings (216%) and avoided undersized cod. This difference in response of different fleets suggested that implementation of CQM, for instance in the context of the European Common Fisheries Policy, should consider fleet characteristics. It seemed that larger vessels in this study more easily adapted their behaviour to new management regimes and that the quota bonus opened up new fishing strategies, that were not envisaged during the implementation.  相似文献   

19.
The Gulf of Mexico Fishery Management Council determined that previous management of the grouper and tilefish fisheries in the northern Gulf of Mexico were not meeting management goals, and developed a catch shares program using individual fishing quotas (IFQs) beginning in January 2010 in order to more effectively manage these fisheries. An IFQ is a management method in which individual fishers and corporations are allocated the right to harvest a percentage of a fishery's total allowable catch, thus specifying how much of a particular species each fisher can harvest. This study makes use of a mail out survey to document the perceptions of fishers, seafood wholesalers, fisheries managers, and academics with an interest in the (northern) Gulf of Mexico grouper and tilefish IFQ program. While fishers, seafood dealers, fisheries managers, and academics all acknowledge that the IFQ program will create some problems, commercial fishers and dealers were far more skeptical of the alleged benefits of IFQs. Moreover, larger commercial operators were more inclined to agree with managers and academics that the IFQ program will produce several benefits for their operations and the fisheries. Some smaller operators believe that they will be driven to ignore the new rules or be forced out of business. In the future, the Gulf Council might do two things: put a bit more effort into making fishers aware of the potential benefits of IFQs, and develop alternatives with more flexibility perhaps working more closely with communities of fishers, who prize their independent way of life above all else.  相似文献   

20.
A socio-economic assessment was conducted at Vanga, Shimoni, Majoreni and Gazi villages in the Kenyan south coast with focus on the sea cucumber fishing patterns, the social and economic characteristics of the fisher communities, the contribution of sea cucumbers to the local livelihoods, and analysis of the management systems. The results indicate that sea cucumber fishers are mainly men. Fishing is done in sub-tidal areas (3–10 m deep) and inter-tidal areas depending on the species being targeted. Those who fish in the sub-tidal areas do skin diving without using SCUBA diving gear. Sea cucumber fishing is heavily done during the northeast monsoon season when the sea is calm and water is clear. About 32% of the sea cucumber fishers also collect other marine products such as octopus. The sea cucumbers are sold fresh from the sea to local first level middlemen who process and sell them to the second level middlemen and exporters in Mombasa. The fishers occasionally borrow money from first level middlemen especially when they fail to catch sea cucumbers but this in turn creates conditions of dependence and possible exploitation. Almost all sea cucumber fishers have stated that they are not willing to make sea cucumbers part of their daily diet. The economic value of the product was substantial; the average monthly revenue for dry sea cucumbers in the area was estimated to US$ 8000. The relative highest profits are derived from juvenile species, thus there is an economic incentive hindering local stocks to reach sexual maturity, which in turn may create a situation in which recruitment success is highly dependent on faraway populations. The present management system falls into general fisheries regulations and was found weak. No specific management plan for sea cucumbers was found.  相似文献   

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