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1.
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   

2.
Spatial approaches gain importance in the governance of marine practices and their environmental impacts. Harmful effects of fishing gear on marine habitats is seen as a considerable spatial conflict that needs to be resolved. One of the most severe measures is the instalment of ‘no take zones’. In the certification programme of the Marine Stewardship Council (MSC) this measure is considered to be a last resort. MSC provides a telling example of ‘informational governance’, that is, a mode of environmental governance wherein information plays a centripetal but often also contested role. Such governing through information is different from conventional state-led decision-making processes. This paper assesses the way informational processes in MSC have affected the settlement of the spatial conflict between plaice fisheries and sensitive habitats in the North Sea. It concludes that information is a formative force in bringing about sustainable fisheries but leads to different outcomes even if the target species and fishing methods are very much alike. This is due to the (nationally) specific informational interactions between non-state actors, especially fishermen and environmental Non-Governmental Organizations. Even though information in marine governance should be science-based, other information (brought in by these actors) is extremely relevant in designing spatial measures.  相似文献   

3.
The United Nations General Assembly in 2006 and 2009 adopted resolutions that call for the identification and protection of vulnerable marine ecosystems (VMEs) from significant adverse impacts of bottom fishing. While general criteria have been produced, there are no guidelines or protocols that elaborate on the process from initial identification through to the protection of VMEs. Here, based upon an expert review of existing practices, a 10-step framework is proposed: (1) Comparatively assess potential VME indicator taxa and habitats in a region; (2) determine VME thresholds; (3) consider areas already known for their ecological importance; (4) compile information on the distributions of likely VME taxa and habitats, as well as related environmental data; (5) develop predictive distribution models for VME indicator taxa and habitats; (6) compile known or likely fishing impacts; (7) produce a predicted VME naturalness distribution (areas of low cumulative impacts); (8) identify areas of higher value to user groups; (9) conduct management strategy evaluations to produce trade-off scenarios; (10) review and re-iterate, until spatial management scenarios are developed that fulfil international obligations and regional conservation and management objectives. To date, regional progress has been piecemeal and incremental. The proposed 10-step framework combines these various experiences into a systematic approach.  相似文献   

4.
Large intensity and diversity of human activities result in an increase in complexity in the utilization of space. This paper describes the fisheries and a method to map fishing efforts and catches of different fleets by combining vessel monitoring system (VMS) data and logbook data. The method makes it possible to explore the spatial and temporal variability of fishing and the potential impacts of proposed management measures on the fisheries. The method is proposed to be used in the development of management plans for marine protected areas such as Natura 2000 sites, designated to protect vulnerable habitats and species.  相似文献   

5.
The East Sea, with an average depth of 1700 m, has long been subject to heavy fishing pressure, resulting in derelict fishing gear. Most derelict fishing gears, such as fishing nets, fishing ropes, and crab pots, sink to the seabed and do not degrade. This gear results in “ghost fishing,” which has adverse impacts on deep benthic habitats. Recently, the Korean government has started to remove derelict fishing gears from the deep seabed of the East Sea by bottom trawling with heavy hooks (50–80 kg) and ropes. A total of 207.8 and 252.2 tons of marine debris in 2009 and 2010, respectively, were removed from the seabed, most of which were derelict fishing gears. Contrary to monitoring surveys and clean-up in shallow waters, removal of marine debris from remote deep habitats is much more difficult and dangerous for removal crews.  相似文献   

6.
This article is an analysis of observed changes in the level of fishing effort and the spatial distribution of fishing effort following implementation of a marine reserve off the California coast. The Rockfish Conservation Area (RCA) closes the area between depth contour based boundaries to commercial trawl fishing. In this analysis, commercial fishing vessels are grouped based on their level of fishing effort within the closed area prior to the closure in order to compare changes in effort levels between groups. The results suggest that the RCA may have had a small effect on the level of fishing effort in the California groundfish trawl fishery. Spatial distribution of fishing effort before and after implementation of the marine reserve is also compared. Some concentration of effort occurred along parts of the closed area boundaries. This pattern suggests the “fishing the line” behavior noted in the marine reserve literature, but other possible explanations exist including the effects of coincident changes in other regulations and changing bioeconomic conditions.  相似文献   

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.
A statutory two hundred and six square kilometre ‘closed area’ in Lyme Bay, South West England entered into force on the 11 July 2008 to protect the reef substrate and the associated biodiversity from the impacts of trawling and dredging with heavy demersal fishing gear. This case study provides an example of how the ecosystem approach has been incorporated into decision making for marine nature conservation and shows that despite sound ecological knowledge of a marine area, the current reliance on traditional neo-classical economic valuations for marine spatial planning can obscure other issues pertinent to the ecosystem approach. With the Government seeking win–win scenarios for stakeholders in the designation of Marine Conservation Zones under the Marine and Coastal Access Act, experience of marine spatial planning in Lyme Bay has revealed that a win–win must be a long-term goal based on a thorough evaluation of the environmental, social and economic values of marine biodiversity.  相似文献   

9.
Precious corals have been commercially exploited because of their legendary and cultural importance for many centuries in the Mediterranean and for almost one century in the Northwest Pacific. Although the precious coral fishery in Taiwan dates back to the 1920s, relevant studies on biology and ecology of resources are relatively scarce. The management of the precious coral fishery in Taiwan was officially instituted in January 2009, when data on the catch and effort of the fishery were recorded. In this study, the catch-effort data of the fishery were examined to explore the temporal and spatial patterns in composition and abundance of Corallium and Paracorallium spp. around Taiwan. A total landing of 3233.0 and 2906.8 kg precious corals were recorded for 2009 and 2010, respectively. Less than 5% of those amounts were from live colonies. A high proportion of fossilized colonies in the catch reflect the non-selective nature of the fishing gear; however, the factors that cause colonies to collapse are not exclusive to the impact of the fishery. Momo coral was dominant in the production for both years, followed by Miss coral. The total production of precious corals correlated positively with fishing efforts, while a weak relationship was found between the production of live colonies and fishing efforts. The fishing efforts mainly aggregated in designated fishing ground A (DFG-A) for both years, while the production of live colonies mainly occurred in DFG-E. The monthly occurrence rate of live colonies decreased over the past 2 years. Although fluctuating significantly, the CPUE of dominant species exhibited an apparent decreasing pattern. High aggregation of the fishing efforts in specific regions and low numbers of live colonies in the production should be carefully taken into account when amending management regulations in the future. The establishment of marine protected areas, in addition to the strict controls that already apply, should be considered to not only sustain the population structure of the sessile animals but also their function in the marine ecosystem.  相似文献   

10.
为研究南海外海鸢乌贼渔场范围与海洋环境因子之间的联系,本文根据2013?2018年广西壮族自治区北海市灯光罩网渔船在南海外海的鸢乌贼生产数据和海洋环境遥感数据,对鸢乌贼渔场范围的时空分布与海表面温度(SST)、海表面高度(SSH)和海表面叶绿素a (Chl a)浓度的关系进行研究。结果表明:在5°~20°N,108°~118°E海域内,SST、SSH、Chl a 浓度3个环境因子对鸢乌贼渔场范围的时空分布影响较大。其适宜的SST、SSH、Chl a浓度分别为:25~31℃、46~80 cm、0.05~0.27 mg/m3,其渔场重心由南向北转移。此外,通过对2013?2018年1?12月的单位捕捞努力量渔获量(CPUE)与海洋环境因子的关系进行K-S检验,结果显示CPUE和海洋环境因子之间没有显著性差异,即SST、SSH、Chl a 浓度3个环境指标可以有效地表征鸢乌贼资源密度和中心渔场分布状况。  相似文献   

11.
Heino O. Fock   《Marine Policy》2008,32(4):728-739
A method is presented to define principal areas for fisheries at high spatial resolution applicable to be implemented into marine spatial planning procedures. Vessel monitoring system (VMS) data from 2005 to 2006 are acquired to determine vessel-based fishing effort. Principal areas for the German exclusive economic zone (EEZ) are defined as areas in which 75% of the effort of either year is carried out. Examples are given for the 5 most abundant fisheries in the German EEZ in terms of vessel-based effort, i.e. gill netting, pelagic trawling, demersal otter board trawling and beam trawling >300 and <300 HP. A historical comparison for demersal otter board trawling shows relative stability of spatial utilization patterns in the North Sea section of the EEZ.  相似文献   

12.
以莱州湾为例,基于GIS和地理空间模拟框架,结合海洋生态红线区分布,建立了海域使用活动对海洋生态环境的潜在压力评估模型,空间量化评估多种海域使用活动对海洋生态环境的潜在影响。结果显示,多种海域使用活动的潜在压力总体呈近岸高于远岸、湾顶>东部>西部的分布特征;压力高值区集中于距岸10 km以内海域和5 m水深以内海域;海洋特别保护区、海洋自然保护区及重要河口生态系统等类型的海洋生态红线区受到开放式养殖、围海养殖、盐业用海活动的压力较大,需要对其进行重点监控。研究揭示了莱州湾海域使用活动对海洋生态环境潜在压力的空间分布格局,为海洋生态红线落地实施和海域使用管理提供决策依据。  相似文献   

13.
An assessment of management effectiveness of Kenya's oldest marine protected areas (Malindi and Watamu) was conducted within the framework of a regional assessment in Kenya, Seychelles and Tanzania. Biophysical, socio-economic and governance indicators were used to assess the delivery of MPA management objectives. Results indicate that the Malindi and Watamu marine parks that are no-take areas are making progress towards meeting their stated objective of biodiversity conservation. The 1997–1998 ENSO related bleaching event caused the greatest single measurable impact on the coral reefs of the marine parks leading to very high levels of coral mortality. The marine reserve where fishing is regulated was less effective in meeting its objective of sustaining community livelihoods. The weakest trends were related to the development of governance structures. A combination of management inefficiencies due to overlapping mandates, financial and administrative constraints, and inadequate stakeholder participation interacted to reduce the ability of the MPAs to fully achieve their objectives.  相似文献   

14.
Nephrops norvegicus is an essentially sedentary species of lobster that forms the basis of valuable fisheries in the northwest Atlantic and western Mediterranean. Fishers exploiting a sedentary stock are likely to visit the most profitable (highest catch rate) areas first. Such spatial targeting of fishing effort is likely to have important consequences for stock monitoring and assessment. We used underwater television surveys of Nephrops burrow densities on the Farn Deeps grounds, northeast England, to describe changes in abundance and distribution between the beginning and end of a winter fishing season. Above a threshold of c. 0.6 burrows m–2, overwinter depletion increased with burrow density, consistent with fishing effort being targeted at the highest densities. A simple simulation model showed that this pattern of mortality is an expected consequence of spatially targeted fishing behaviour. The model also predicted that there is decreased spatial variability in density after fishing. An overall decrease in variability was not evident from the survey data, but geostatistical analysis indicated that there was “flattening” of the density profile along a north‐south axis, consistent with the dominant direction of commercial trawling. We concluded that Nephrops fishers are able to find and exploit the highest densities of their target species. A potential consequence is that catch per unit effort (CPUE) data used to monitor trends in this stock potentially could mask declines in stock abundance. CPUE might be more effective if analysed at finer spatial scales, but this is not currently possible. In the absence of these fine scale commercial data, fishery‐independent surveys (e.g., underwater television) are an important source of information on trends in stock abundance.  相似文献   

15.
Analysis of cumulative human impacts in the marine environment is still in its infancy but developing rapidly. In this study, existing approaches were expanded upon, aiming for a realistic consideration of cumulative impacts at a regional scale. Thirty-eight human activities were considered, with each broken down according to stressor types and a range of spatial influences. To add to the policy relevance, existing stressors within and outside of conservation areas were compared. Results indicate the entire continental shelf of Canada's Pacific marine waters is affected by multiple human activities at some level. Commercial fishing, land-based activities and marine transportation accounted for 57.0%, 19.1%, and 17.7% of total cumulative impacts, respectively. Surprisingly, most areas with conservation designations contained higher impact scores than the mean values of their corresponding ecoregions. Despite recent advances in mapping cumulative impacts, many limitations remain. Nonetheless, preliminary analyses such as these can provide information relevant to precautionary management and conservation efforts.  相似文献   

16.
The ecological consequences of coral mining can be severe, with immediate reduction in reef-associated biodiversity and longer term implications for linked habitats such as mangrove forests and seagrass meadows. However, research into the effects of coral mining must take into account other environmental processes which may affect reef communities and the socio-economic context within which coral mining takes place if appropriate and proportionate management responses are to be identified. This article builds upon recently published research detailing the adverse effects of coral mining in Indonesia to illustrate the significance of these points. We use the previous paper to demonstrate that accurate identification of the ecological impacts of coral mining requires the use of appropriate control sites and recognizing natural stresses which may account for short-term variability in ecological parameters. We also underline the need to appreciate that government institutions can directly or indirectly facilitate coral mining, whilst proposed alternative income-generating activities intended to reduce coral mining should be tailored to the local economic, cultural and environmental context if they are to gain community support. This demonstrates the value of an integrated approach to analyzing marine resource usage which combines information from the natural and social sciences to address environmental problems such as coral mining.  相似文献   

17.
The social dimensions of marine protected areas (MPAs) play an important role in MPA success, yet these social dimensions are little understood. We explore the social impacts arising from the establishment of an MPA using Lyme Bay (south west England) as a case study. Through a series of small group semi-structured interviews the social impacts experienced by fishermen (mobile and static gear), recreational users (divers and sea anglers) and recreation service providers (charter boat and dive businesses) were explored. The social impacts expressed varied according to activity in which the stakeholder group engaged. Negative themes included lengthening fishing trips, tension and conflict, fishermen identity, equity and uncertainty in the long-term. Positive themes included improved experiences for both commercial fishermen and recreational users, and expectations for long-term benefits. These impacts need to be understood because they influence stakeholder behaviour. Failure to interpret stakeholder responses may lead to poor decision-making and worsening stakeholder relations. These findings have implications for the success of the MPA in Lyme Bay, but also for the future network of marine conservation zones around the UK. Any assessment of MPA impacts must therefore identify social as well as economic and environmental change.  相似文献   

18.
Information about spatial patterns of recreational boating is important for managing environmental, safety, and social impacts. However, traditional spatial mapping techniques such as remote sensing are often unable to project entire vessel routes or to link with other important data such as demographics, activities, or purpose of trip. This study, conducted in a part of Canada’s southern Strait of Georgia, uses an on-the-water-questionnaire to map recreational boating distribution/density in a complex, multiple-use marine setting. Goals of this study were to explore an on-the-water questionnaire as a means of capturing boating distribution and density, explore the potential contributions of such information to marine spatial planning, and assess the strengths and limitations of the method. Boaters (n=519) were intercepted while engaged in boating trips and were asked to plot the route of their trip on a map of the region. Information was imported into ArcGIS for analysis and display of vessel distribution and density. The resultant spatial dataset has a number of applications for marine spatial planning and management. Strengths of this method include collection of entire vessel routes, linking spatial data to questionnaire variables, and a high response rate. Limitations include some bias towards sample sites and issues of respondent accuracy, as well as cost and effort. Recommendations for management and research are made.  相似文献   

19.
Coastal lagoons can be characterised by strong environmental changes along the outer marine‐inner brackish gradient, which are reflected in the patterns of distribution of organisms and composition of assemblages. Close to the sea the assemblages are dominated by marine animals, while in the innermost confined areas, there would be estuarine taxa and organisms typical of organically‐enriched areas. During the last decades, human impact has been severe in these habitats and has often profoundly altered the distribution of animals and plants along the gradient. In this study we have analysed the distribution of macrofauna along the outer marine‐inner brackish gradient in five Italian lagoons, affected by severe human disturbance on the Adriatic, Tyrrhenian and Sardinian coasts. We aimed to measure changes in the composition of assemblages according to the distance from the sea, consistent among lagoons and time, after the occurrence of eutrophication, repeated distrophic crisis and other human interventions. We considered existing data from campaigns done during 1994, 1995 and 1999. We arranged different datasets according to the available data, in order to measure the spatial distribution of macrofauna genera with distance from the sea and through time. Analyses showed differences among assemblages related to the gradient. Nevertheless, the species characterizing the assemblages were all typical of organically‐enriched areas, which testified to an impoverishment of diversity and functioning of all these systems.  相似文献   

20.
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