Considering community allocations: Power and the politics of enclosure in the Gulf of Alaska

In 2012, the North Pacific Fishery Management Council initiated the process of designing a new management structure for the Gulf of Alaska trawl groundfish fleet. The new program is currently structured as a catch share program and driven by the need to end the ‘race for fish’ and provide the trawl fleet with the tools to reduce bycatch. To date much of the discussion among policy makers and stakeholders has centered on community protection measures and how best to avoid the negative social and economic impacts of catch share programs including impacts to crew, consolidation and the flight of quota and resource wealth from Gulf of Alaska fishery dependent communities. This paper examines how community protection measures related to the distribution of benefits and access to fishery resources are considered and challenged in the North Pacific today. Special attention is given to the ongoing debate surrounding the potential inclusion of an initial allocation to place-based Gulf of Alaska communities via a Community Fishing Association. As part of this effort, this paper examines the political space and underlying power dynamics in which consideration of alternatives to the commodification of fishing rights occurs.     

Historical mercury trends recorded in sediments from the Laguna del Plata,Córdoba,Argentina

The main carrying phases of mercury (Hg) were analyzed in a 120 cm sediment core taken at the Laguna del Plata (LP), a small lake connected to the main water body of Laguna Mar Chiquita (LMC) during highstands. LMC is considered to be one of the largest saline lakes in the world representing a sensitive climatic indicator due to its frequent lake level variations at millennial and interdecadal scale like the last ones that started early in the 1970s and after 2004. Total particulate Hg (Hg_TP) concentrations vary between ∼13 and ∼131 μg kg⁻¹ indicating a system with low pollution. Selective extractions with ascorbate, HCl and H₂O₂ were performed in the sediments and they revealed that Hg is associated mainly to reactive sulphides in the base of the core, while in the middle and upper part the organic matter seems to be the main Hg-bearing phase. The highest and most important peak was found in sediments accumulated between 1991 and 1995. More than a punctual source of pollution, this peak is likely related to two eruptive events occurred in the Andean Cordillera in this period: the eruption of Hudson volcano in southern Patagonia that occurred in 1991 and the one of the Láscar volcano in northern Chile that occurred in 1993. In both cases, the respective ash plumes were documented to have reached the Laguna del Plata region.     

广东海域模拟人和无动力渔船海上漂移试验研究

为探讨海上搜救目标无动力渔船和落水人员在海水中的漂移规律,对现有海上搜救目标漂移轨迹预测模型进行评估与改进,国家海洋局南海海洋工程勘察中心于2011年2月和4月在广东近岸海域开展了3组模拟人和2组无动力船海上漂移试验。试验发现模拟人与无动力船大部分时刻的漂移轨迹位于下风向的右侧,80%以上的时刻漂移轨迹位于海流流向和下风向的矢量合成区间内。以漂移速度为应变量,流速和风速为自变量进行二元回归分析发现,广东海域的模拟人和无动力渔船的流致漂移参数约为1.0,风致漂移参数分别为0.019和0.038。     

Characterisation of the recreational fishery for southern rock lobster,Jasus edwardsii,in Tasmania,Australia: Implications for management

Southern rock lobster (Jasus edwardsii) support significant commercial and recreational fisheries in Tasmania, Australia. Since the mid 1990s the number of persons holding recreational lobster licences increased by over 80%, with c. 15 500 persons licensed in 2002/03. Assessment of the recreational fishery has been undertaken periodically since 1996 using a telephone‐diary survey method. The fishery was concentrated off the south‐east and east coasts of Tasmania and characterised by strong seasonality in catch and effort, which peaked markedly early in the fishing year (November‐January). Although pots were the most popular fishing method, daily catch rates by divers were more than double those for pots. Divers selectively harvested larger lobsters than those taken by pots and more frequently attained the daily bag limit of 5 lobsters. The estimated recreational harvest increased significantly since 1996/97 and in 2002/03 effectively reached a management trigger level of 10% of the total allowable commercial catch, flagging a review of recreational management arrangements.     

The effects of spatial targeting of fishing effort on the distribution of the Norway lobster,Nephrops norvegicus,on the Farn Deeps grounds,northeast England

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.     

The effects of barotrauma on five species of South African line-caught fish

Management measures for South African line-caught fish include output controls such as closed seasons, bag and size limits and no-take moratoria. The main condition for these measures to be effective is that undesirable catches can be successfully released. However, most of the line-caught fish species are susceptible to barotrauma, a condition caused in physoclists by the rapid reduction of hydrostatic pressure during the ascent to the surface during capture. We investigated the effects of barotrauma on five commercially important species: roman Chrysoblephus laticeps, silver kob Argyrosomus inodorus, hottentot Pachymetopon blochii, santer Cheimerius nufar and carpenter Argyrozona argyrozona. A classification of the external signs of barotrauma was developed and internal and external signs of barotrauma were examined in relation to fishing depth and fish size, and compared between species. Immediate post-release mortality was investigated during a catch-and-release experiment. Medium-term survival of C. laticeps (~1 d) was examined by returning fish to depth in cages and subsequent monitoring on SCUBA. Our results indicate that most of the fish experience barotrauma even when caught at relatively shallow depths. External signs include extension of the inflated, everted stomach through the mouth, distended eyes, protrusion of the hind-gut and other organs through the cloaca, and gas bubbles in the dermal tissue between the fin rays. The absence of any obvious external signs of barotrauma can be misleading as dissections of such fish revealed ruptures of the swimbladder and other internal injuries consistent with barotrauma. Our results indicate that there might be significant post-release mortality, a factor that needs to be taken into account during stock assessment predictions and during the implementation of catch restrictions.     

An assessment of participation,catch and effort in the KwaZulu-Natal shore-based marine linefishery,with comments on management effectiveness

The primary purpose of this study was to evaluate the effectiveness of current management of the KwaZulu-Natal (KZN) shore-based marine linefishery. Methods used included a stratified-random creel survey and an associated questionnaire survey. The study was undertaken between February 2009 and January 2010. Total participation ranged between 41 283 and 68 087 shore-anglers. Results show that there has been little change in participation in the KZN shore-fishery since 1994–1996. In contrast, total angler effort (779 382–843 702 angler-days y^?1) has decreased substantially over the past 13 years. Overall catch per unit effort (CPUE) for the KZN shore-linefishery amounted to 0.18 ± 0.3 fish angler^?1 h^?1 or 0.07 ± 0.13 kg angler^?1 h^?1. In all, 84 fish species, belonging to 39 families, were recorded in catches of shore-anglers during the study period. Only five species accounted for 75% of the catch recorded along the coast (Sarpa salpa 34.8%, Pomatomus saltatrix 14.7%, Diplodus capensis 14.5%, Pomadasys olivaceum 6.5% and Rhabdosargus holubi 4.9%). The total annual catch for the KZN shore-linefishery was estimated between 249.2 and 276.7 t y^?1 (or 636 589–706 995 fish y^?1). Analysis of overall CPUE, catch composition and total catch in the shore-based linefishery of KZN suggested that it is currently in a relatively stable condition and that little change has occurred over the past 13 years. However, comparisons of species-specific CPUE values from this study with recent literature suggest that some species (e.g. Argyrosomus japonicus) are severely overexploited. Over the past few decades there seems to have been a gradual transition in landings from long-lived, high trophic-level, piscivorous fish (e.g. A. japonicus) to more short-lived, low trophic-level species (e.g. S. salpa). The results therefore suggest that present exploitation levels may not be sustainable for certain slow-growing, long-lived fish species. Current management regulations appear to have limited effectiveness based on poor angler compliance and knowledge of the regulations. In this regard, it is important to consider alternate management measures that may offer more effective protection to fish and at the same time be more easily understood by all anglers in the linefishery. Recommendations for improved management and the importance of the establishment of an effective MPA network are briefly discussed.     

Temporal changes in kelp forest benthic communities following an invasion by the rock lobster Jasus lalandii

The rock lobster Jasus lalandii expanded its centre of distribution south-eastwards into an area known as ‘East of Cape Hangklip’ on the south-west coast of South Africa in the early 1990s. Using historical and present data, we analysed differences in the abundance of key species and functional groups between the pre- and post-rock lobster invasion periods at two sites along that coast: Cape Hangklip and Betty's Bay. Pre-1989, lobsters were absent, but after 1995 they reached densities approximating 0.4–0.8 m^?2. Benthic community composition also changed significantly with herbivores being abundant whereas macroalgae and sessile invertebrates were scarce pre-invasion. We attribute the decline of herbivores to the direct effects of lobster predation, in turn indirectly promoting macroalgae. Post-invasion sessile invertebrates and macroalgae increased by 2 600% and 453% respectively, whereas herbivores declined by 99.3%. The virtual elimination of the sea urchin Parechinus angulo-sus by rock lobsters has substantial implications for the commercial harvesting of the abalone Haliotis midae, because its juveniles are intimately associated with this urchin. The lobster invasion has thus not only led to a regime shift of the ecosystem but has also substantial economic consequences, which calls for an ecosystem approach to the management of the pool of commercially exploited resources in this region.     

水上光伏发电系统雷电防护技术

光伏发电系统是一种清洁、安全、便利、高效的新兴发电产业。近年来,以"渔光互补"为代表的水上光伏发电系统发展显著,很大程度上解决了建设传统光伏电站土地资源稀缺等难题,有效提高了土地综合利用效益。为了防止和减少雷电对水上光伏发电系统造成的设备损害和人身伤害,确保光伏发电系统安全可靠运行,通过分析所在地的雷电环境特征及雷电危害途径,结合水上光伏发电系统的布置形式和结构特征,提出综合性雷电防护方案,采取由接闪器、引下线和接地装置组成的外部防雷装置来预防直击雷危害;综合应用等电位连接和共用接地系统、屏蔽及合理布线、安装电涌保护器来有效减少雷电过电压,以及雷击电磁脉冲对光伏发电系统造成的电气和电子系统损坏。     

论渔业法之违反捕捞许可规定到共同管理渔区作业行为的法律责任

近年来我国渔业作业群体的数量明显增多,同时违反捕捞许可到共同管理渔区作业的违法行为也日益严重。在《中华人民共和国渔业法》及相关渔业立法中已经存在明确界定,但是对于法律责任没有具体阐明,严重影响了渔业活动的正常秩序与渔业资源的可持续发展。文章根据违反捕捞许可到共同管理渔区作业的现状出发,结合渔业法等相关规定,分析增设法律责任的必要性与可行性,提出完善相关法律责任,细化责任认定;加大惩治力度,提高违法成本等建议。