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1.
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   

2.
Understanding the socio-economic drivers underpinning fishers' decisions to target elasmobranchs is considered vital in determining sustainable management objectives for these species, yet limited empirical data is collected. This study presents an overview of elasmobranch catch, trade and socio-economic characteristics of Zanzibar's small-scale, artisanal fishery. The value of applying this information to future elasmobranch fisheries policy is demonstrated. In August 2015, interviews were conducted with fishers (n = 39) and merchants (n = 16) at two landing sites, Kizimkazi-Dimbani and Mkokotoni, along with the main market site in Stone Town. Additionally, elasmobranch catches were recorded across the same locations between June and August 2015. Elasmobranchs were listed as target species by 49% of fishers interviewed. Whilst most fishers (n = 30) stated that 76–100% of their household income came from fishing, there was variation in how elasmobranch catch and trade contributed. One-third of fishers (n = 36) that caught and sold elasmobranchs reported that 41–60% of their income came from elasmobranch catch. However, for some fishers (n = 8) elasmobranch catch represented 0–20% of their income, whilst for others (n = 4) it represented 81–100%. Differences in fisheries income and elasmobranch price could be attributed to several interacting factors including season, weather, fishing effort, fishing gear, target catch and consumer demand. Further, elasmobranch price was influenced by size and species. The study revealed information on catch, trade, markets and socio-economy that is important for future research, conservation and management of elasmobranchs and fisheries in Zanzibar. The methods utilised have potential for broader application to understudied, artisanal elasmobranch fisheries in the western Indian Ocean.  相似文献   

3.
This article investigates practical aspects and limitations of various fishery management techniques. Restrictions on catch and fishing effort (active regulations) are described, and the authors point out that catch restrictions are less robust scientifically than effort restrictions. Spatial — temporal restrictions, gear restrictions, and restrictions on the nature of the catch-which are passive with respect to fishing mortality-are reviewed and it is concluded that fishing mortality is theoretically unbounded when only passive methods of fisheries management are applied.  相似文献   

4.
East coast rock lobsters Panulirus homarus are collected by the indigenous people of the Wild Coast, in the Eastern Cape, South Africa, and are sold to coastal hotels and holidaymakers. The South African government has proposed a small-scale commercial fishery based on P. homarus to improve socio-economic conditions in that region. Catch data and information on fishery operations were collected for the artisanal fishery from Coffee Bay, Presley Bay, Port St Johns and Mbotyi, as well as from a commercial buying station near the Mdumbi Estuary, between March 2003 and October 2005. The catch per unit effort of rock lobster poling varied from 13.5 ± 7.7 fisher–1 outing–1 at Port St Johns to 5.9 ± 3.1 fisher–1 outing–1 at Coffee Bay, but the number of fishers or fishing frequency could not be verified. About two-thirds of the lobsters caught (69%) were smaller than the minimum legal size. Hotels and the buying station complied with size limits, but cottages and campers often bought undersized lobsters. Smaller lobsters (females) are caught by poling than by diving. Geographical variations in poling effort and lobster mean sizes could be indicators of heavy fishing pressure on shallow, inshore reefs. The implications of commercialising the fishery and its associated management are discussed.  相似文献   

5.
Marine reserves and gear restrictions are common forms of marine resource management; they impact on fishers both directly and indirectly. In 2003 New Zealand set net fishers were required to abandon set netting along a substantial section of the North Island′s West Coast in order to eliminate the chance of entangling the critically endangered Maui′s dolphin. A study of some 100 set net fishers, found that the immediate, and short term effects of the 2003 set netting area closures had little impact on the catch and effort levels of fishers. Participation in the fishery increased immediately prior to the restrictions and remained at a similar level for the following four years. Incumbent fishers performed better than new entrants and exiters. Trends in Annual Catch Entitlement (ACE) prices appear not to have been affected by the set net restrictions.  相似文献   

6.
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7.
Understanding fishers’ responses to marine spatial closures is important for both resource users and managers. Fishing is a major recreational activity in Australia, and recreational fishers are key local resource users within the Great Barrier Reef Marine Park. In 2004, implementation of a new zoning plan in the park resulted in a reduction in the amount of area available to recreational fishing. A combination of phone, mail, and face-to-face surveys was used to investigate recreational fishers’ choices and spatial redistribution strategies in response to the reduction in fishing area. Approximately 56% of fishers reported losing at least one of their regular fishing locations under the new zoning plan. Fishers generally compensated by shifting their fishing effort to other areas they knew to be good fishing locations, and by finding new areas that they had not exploited previously. Potential implications of these spatial changes in recreational fishing effort for both the marine park and recreational fishers include changes in fishing frequency and satisfaction, reduced fishing quality, restricted access to areas considered to be of high quality for recreational fishing, increased crowding in areas that remain open to fishing, and increased likelihood of localized depletions in popular recreational fishing locations. Identification of the drivers of the spatial distribution of fishing effort, factors affecting fishers’ choices of locations, and adaptation strategies adopted by fishers provide a valuable tool to help understand the impact of spatial fishing closures on fishers and resources.  相似文献   

8.
The performance of the EU long-term management plan for cod stocks, in force since 2009, is analysed focusing on the human and institutional factors. The plan operates through landings quotas (TACs) and effort restrictions following a Harvest Control Rule, and deploys a novel instrument allowing Member States to ‘buy back’ or increase fishing effort for fleet segments engaged in cod-avoidance measures. The stipulated fishing mortality reductions have not been achieved. On the positive side, the ‘buy-back’ instrument has led to increased uptake of selective gear and implementation of permanent and real-time temporary closures. On the negative side, ignoring the dimension of fishers as reactive agents in the design, the impact assessment, and the annual implementation of the measures has contributed to the failure to adequately implement the plan and achieve its objectives. The main problem is that the landings quotas taken in a mixed fishery did not limit catches because fishers were incentivised to continue fishing and discard overquota catch while quota for other species was available. The effort limitations intended to reduce this effect were insufficient to adequately limit fishing mortality in targeted fisheries, although fishers experienced them as prohibiting the full uptake of other quotas. Recommendations for future plans include (i) management through catch rather than landings quotas, (ii) the internalisation of the costs of exceeding quotas, (iii) use of more selective gear types, (iv) the development of appropriate metrics as a basis for regulatory measures and for evaluations, (v) participatory governance, (vi) fishery-based management, (vii) flexibility in fishing strategy at vessel level.  相似文献   

9.
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   

10.
Tropical shrimp trawl fisheries are unsustainable, and similar sets of management measures are used globally to address the direct and indirect costs of their practices. Yet little is known about shrimp fishers’ perceptions, despite the clear importance of human behaviour in determining the success of fisheries management. This article presents the results of interviews with industrial shrimp trawl fishers from the southern Gulf of California, Mexico, and reveals fishers’ knowledge and attitudes that should be considered when developing management plans for industrial shrimp trawl fisheries. Fishers were asked to comment on problems facing the fishery, management options to address the issues, and the future of the fishery in general. The interviews also elicited new knowledge on effort and valuable components of bycatch, useful to the management process. Among the problems facing the Gulf of California fishery, fishers tended to identify those generated externally—fluctuations in shrimp populations, increases in fishing effort, decreases in shrimp prices and increasing overheads—and thus distance themselves from responsibility for management options. The successes of any mitigation measures for the fishery are likely to depend on proper enforcement and reliable governance, as our study indicates. Should strong enforcement be put in place, then trawl free areas seem to be the most pragmatic way to alleviate problems associated with the fishery; our effort data point to areas that might have greatest acceptance among fishers. A reduction in capacity would clearly complement marine zoning for trawl free areas. In the long run, however, it may be economic extinction of the fishery that reduces pressure on the marine ecosystem.  相似文献   

11.
This study examined the perceptions of fishers from two fishing communities with differing use histories and involvement in the long-standing (16 yr) multiple use Mafia Island marine protected area (MIMP), Tanzania. A randomly distributed questionnaire indicated that 94% of fishers believed that without the MIMP, there would be overfishing, dynamite use, destroyed habitats, and few fish. Fishers were more positive about core zones (no-take fishery closures) than general use zones (areas allowing selective fishing) as a consequence of increases in fishing pressure. Those that reported increased catches and sizes of fish since the creation of the MIMP were more likely to agree with present zone locations and more positive in general about fisheries and conservation planning. Most thought that fish size and gear restrictions were preferable to permanent closures. Perceptions differed among communities and gear users. Community and gear type explained 46% of the variance in responses about the perception that fisheries and conservation are compatible goals. Somewhat surprisingly, these effects were more important than catch increases or involvement in MIMP-related activities. The differences in perception between communities may be partly attributed to different fishing histories. Multiple-use zoning provides a means to identify and resolve conflicts and achieve what are likely universal objectives for fisheries sustainability and conservation.  相似文献   

12.
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   

13.
Understanding the economic value of ocean space is critical for implementing marine spatial planning (MSP). Empirical data from 1999 to 2008 are compiled on the economic values arising from commercial fishing in the Gulf of Maine and adjacent areas. The data are analyzed to characterize factors affecting the spatial and temporal distribution of measures of economic productivity and fishing effort. The analysis consisted of four components: (1) estimation of net revenue at the 10-min square level by season and gear; (2) assessment of variability for catch revenue and catch per unit effort; (3) mapping net revenue and variability in the study area; and (4) estimation of interactions among catch, effort, season, and gear type. The results indicated that, at each location, average fishing efforts exhibited a positive response to increases in expected revenues and a negative response to variability in revenues. Most of the variability in catch revenue can be explained by changes in fishing effort, implying that the spatial patterns of fishery resources are relatively stable at the 10-min square level. An important conclusion is that a spatial scale of at least the 10-min square is appropriate for undertaking MSP involving allocations of commercial fisheries.  相似文献   

14.
The southern rock lobster, Jasus edwardsii, is South Australia's most valuable fisheries resource, with an annual landed value of c. AU$100 million. Approximately 80% of this revenue comes from the southern zone (SZ) rock lobster fishery, which has been managed under an individual transferable quota system since 1993. The total allowable commercial catch is currently set at 1900 tonnes. Long‐term spatial trends in catch and effort were analysed over the period 1970–2005 to investigate possible changes in the spatial dynamics of the fleets as a result of quota introduction. Data indicate that the fishery contracted into three main Marine Fishing Areas (MFAs) after 1993. In particular, the long‐term catch average in MFA 51 decreased from 185.4 tonnes pre‐quota to 59.8 tonnes post quota. This MFA is located in the northern region of the SZ and is one of the furthest MFAs from the main fishing ports in the region. The fishery is also spatially contracted within MFAs. Approximately 80% of the annual catch comes from <60m depth despite catch rates being 2–3 times greater in offshore sites as evidenced from both fishery‐dependent and independent sources. Such trends appear driven by recent market preferences that select for small (<1 kg), red‐coloured lobster that are primarily located on inshore grounds. As a result, fishers now target inshore sites to maximise returns under the quota‐based system. The observed shift in the spatial dynamics of the SZ has clear implications for the biological performance indicators on which the fishery is managed. Specifically, the results highlight the need for a fishery‐independent assessment of the resource that provides estimates of catch rate and biomass independent of current harvest strategies. Preliminary results from a trial survey undertaken in 2005/06 and 2006/07 show higher lobster abundance in lowly exploited offshore sites compared with inshore areas. These trends highlight the need for refined spatial management of the resource, which is the focus of the new management plan for the fishery.  相似文献   

15.
The trawl fishery, which targets Cape hake Merluccius spp. and Agulhas sole Austroglossus pectoralis, takes chokka squid Loligo vulgaris reynaudii as by-catch. Catch and effort data from the trawl fishery for the period 1978–1996 are used to obtain annual estimates of catch rate (catch per unit effort cpue) for that period. Examination of the cpue trend shows a sharp decline in the early 1980s and, in order to identify factors that could have influenced that decline, the distribution of fishing effort is investigated both temporally and spatially. There is a possible change in the incidence of squid-directed catches over time, but their overall scarcity could have had only a small impact on the annual cpue trend. Further, using distribution of fishing effort to evaluate the effects of possible changes in fishing patterns, rather than changes in resource abundance, on the trend in trawl cpue, it became clear that there had been a contraction of the trawling grounds and changes in fishing patterns in relation to depth over time. Finally, a general linear model (GLM) is developed to quantify the effect on cpue of factors such as vessel characteristic, depth and position of the drag, season and target species, so obtaining a standardized trawl cpue index of chokka abundance. Analysis of that trend reveals a mean 7.7% annual decline for the period investigated, which should be interpreted as a strong sign of resource decline.  相似文献   

16.
New Zealand's Quota Management System (QMS) consists of a two tier operational structure: Quota shares in a fishstock provide an Annual Catch Entitlement (ACE) of the total allowable commercial catch (TACC) of the specific fishstock. Fishers operating in a multispecies fishery need a portfolio of ACE that matches the mix of their annual catch. Fishers may own quota shares, and thereby receive the needed ACE allocations or they may operate without quota shares and rely on acquiring ACE in the ACE market. Whatever the fisher's situation, it is common for fishers to both buy and sell ACE during a fishing year as they seek to balance their actual catch against ACE. The incentive to achieve a balance is strong because at year-end fishers whose catch exceeds ACE are required to pay a fee called ‘deemed value’. For many fishstocks the deemed value fee increases sharply as the percentage by which a fisher's catch exceeds their ACE increases. When no ‘unbalanced’ ACE is available for purchase, an overfished fisher may attempt to mitigate their deemed value liability by engaging in arbitrage trading in ACE whereby they buy ACE from other overfished fishers. This study examines the nature and extent of ACE arbitrage behaviour in the New Zealand quota managed fishery. The study finds that the number of fishstocks where arbitrage trading occurs is relatively small and is declining. However, sizeable deemed value mitigation transactions are still evident.  相似文献   

17.
Puerulus settlement has been monitored throughout the western rock lobster Panulirus cygnus fishery for nearly 40 years. These data, in combination with indices of effort and water temperature, were used to produce recruitment‐catch relationships for each 1° transect of latitude in the coastal part of this fishery from Kalbarri to Cape Leeuwin, as well as at the offshore Abrolhos Islands (total of eight transects). The fine spatial scales of these models provided estimates of certain life history traits that are known to affect lobster catches between adjacent fishing ports. This catch modelling showed that the proportions of 3‐ and 4‐year‐old post‐settlement lobsters contributing to the catches varied markedly from the southern to northern transects, suggesting that juvenile lobsters grow substantially faster in the warmer northern and offshore waters of this fishery. These proportions provide accurate estimates of juvenile growth rates, which are vital in the construction of location‐specific growth algorithms required by the age‐structured models used in the management of this fishery. Model estimates of density‐dependent mortality were greater in the more densely populated centre of the fishery and markedly lower at the northern and southern limits of this species distribution. Annual increases in fishing efficiency were also found to be lowest at the northern and southern extremes of the fishery and greatest in the centre of the fishery, where technology advances and increased fleet mobility have enabled the fleet to increase efficiency by 1–3% each year. Catchability (q) was found to be most influenced by water temperatures in the cooler southern transects, whereas at the Abrolhos Islands, changes in water temperature produced almost no discernable change in q. The catch modelling was also used to quantify the impact of management changes introduced in the 1993/94 fishing season. Increased protection of female lobsters and an 18% pot reduction resulted in a 3–4% permanent reduction in the catch rates of lobsters throughout most of the coastal fishery, whereas at the offshore Abrolhos Islands, catch rates increased by c. 20%, presumably owing to a reduction in the level of pot saturation.  相似文献   

18.
New Zealand's exclusive economic zone encompasses a significant fishery that is managed by a market-based quota management system. Since the introduction of this regime in 1986 over 3000 fishers have exited the industry. These exiters are predominantly small-scale fishers. This study profiles a sample of the exiters, using information provided on the Ministry of Fisheries database and through a questionnaire sent to the exiters themselves. The profile includes information on the scale of exiters, their typical methods of fishing, the importance of time and exit price to the exit decision, and post-exit employment outcomes.  相似文献   

19.
Fishers' responses to changes in resource access through the imposition of marine protected areas can be a critical factor influencing the likelihood of achieving management objectives.Face-to-face interviews with 114 commercial and charter fishers were conducted to investigate their responses and adaptation strategies to the increase in the size and number of no-take zones imposed by the 2004 Great Barrier Reef Marine Park zoning plan. Despite holding positive attitudes towards marine biodiversity protection, fishers were generally unsupportive of the new zoning plan 5 years after its implementation. Fishers' lack of support was related to the perception that they had not been adequately engaged in the rezoning process and the perception of significant impacts of the zoning plan on fishing businesses. Fishers generally believed that the new zoning plan had a negative impact on their access to productive fishing areas, the numbers of fish they catch, the profitability of their fishing business, and their personal income. In response to the new no-take zones, fishers tended to redistribute their fishing activity to locations closer to their home port, and to locations already known to them through their previous fishing, resulting in an increase in high density fishing locations within the park. Despite the impacts that fishers experienced, most reported that they have adapted their fishing activity and fishing business at least moderately well to the new zoning plan, suggesting that many of the impacts experienced by fishers might be short-term and may decline over time as fishers learn to adapt to the new zoning system. The information provided should prove valuable as a baseline for continued monitoring of the costs and benefits of the Great Barrier Reef Marine Park rezoning into the future.  相似文献   

20.
An assessment of catch and effort in the Eastern Cape shore and skiboat linefisheries was undertaken between 1994 and 1996 by means of roving creel and access point surveys. Catch-and-effort data were obtained from direct observation of 3 273 shore-fishers, 172 recreational and 223 commercial skiboat outings. Total effort in the region was high at 903 186 fisher-days year?1 in the shore fishery and 64 266 and 24 357 fisher-days year?1 in the commercial and recreational skiboat sectors respectively. The fisheries are multispecies in nature. The shore fishery consisted of 66 species, the recreational skiboat fishery 44 species and the commercial skiboat fishery 48 species. Just 10 species accounted for 75, 83 and 90% of the catch of the shore, recreational and commercial skiboat fishery respectively. The average catch per unit effort (cpue) was low in all sectors, 1.15 kg fisher?1 day?1 in the shorefishery, 9.4 kg fisher?1 day?1 in the recreational skiboat fishery and 21.5 kg fisher?1 day?1 in the commercial skiboat fishery. Catch data showed that professional and club anglers are more successful fishers. Comparisons with historic records for Port Elizabeth revealed that the cpue in the shore fishery had declined markedly, whereas the total effort increase was negligible (0.1%). In addition, the species composition of the fishery has changed.  相似文献   

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