Strength in diversity: fish sanctuaries and deep-water pools in Lao PDR

Abstract  Fish sanctuaries are types of aquatic protected areas common throughout the landlocked country of Lao PDR. The key to their successful implementation in Laos appears to be local support. Therefore, they fit well within the context of community-based fisheries/co-management programmes. Fish sanctuaries are almost always established in deep-water pools, which serve as important dry season refuges for fish. The best-known fish sanctuaries in Laos are known as Fish Conservation Zones (FCZs), and are found in the mainstream Mekong River in Khong district, Champasak province, southern Laos. In Khong, there is increasing evidence that FCZs established by villagers, but with government support, are important places of concentration for various fish species. FCZs can benefit fish stocks, especially relatively sedentary species, but also highly migratory ones. FCZs are not panaceas for solving all the fisheries problems in Laos or the Mekong River Basin, but they represent important management tools that should not be overlooked.     

借鉴国外ITQ管理经验促进我省渔业管理的发展

本文收集国内外有关ITQ管理的资料，介绍了ITQ管理制度的特点和实施该制度应具备的一些必要条件。ITQ制度能有效地保护渔业资源，减少政府过多的行政干预，抑制过度投资，体现市场为导向的资源分配方式和有偿使用渔业资源等特点。同时，总结了新西兰实施ITQ制度对渔业产业结构、资源保护和社会经济方面的影响。最后，对我省实施ITQ管理的可能性和渔业管理上采取的相应措施提出了建议。     

Reserve effect of a small North-East Atlantic marine protected area (Arrábida,Portugal) on soft-sediment fish species

1. The implementation of marine protected areas (MPAs) has been widely used as a tool to manage and conserve marine resources and services. Yet, to date, the reserve effect is still weakly evaluated, particularly for soft-sediment habitats.
2. The Arrábida MPA, considered as a biodiversity hotspot, was fully established in 2009 on the west coast of Portugal and is characterized by large expanses of soft-sediment habitats. This MPA was established to protect biodiversity and to ensure the livelihood of the local small-scale fisheries community.
3. Beyond before–after-control–impact (BACI) analyses were carried out on catch data (abundance and biomass) of 351 trammel net sets from experimental fishing campaigns (2007–2019) to study the reserve effect on demersal fish populations.
4. The results show a declining trend in abundance inside and outside the protected area, with significant positive effects only found for undersize commercial species and Solea senegalensis, and a general increase in fish species total length. Despite the lack of any obvious reserve effect, the increase in fish length can be considered as a first sign.
5. Anthropogenic pressures are generalized around the area, and transgressions of the restrictions are frequently observed inside the no-take zone. These can, among other aspects, delay or prevent the expected reserve effects. Therefore, enforcement and/or modification of the spatial plan must be incentivized to achieve the goals of the MPA.

     

Keeping watch on the unwatchable: technological solutions for the problems generated by ecosystem-based management

Ecosystem‐based management is an emerging paradigm influencing the management of commercial fisheries. Increasingly, developed nations are adopting explicit legislation and policy governing the assessment and management of their fisheries against criteria of ecological sustainability. Yet the ability to evaluate ecosystem impacts of fisheries is compromised by a general lack of understanding of marine ecosystem function (beyond the population level) and a lack of robust and practical indicators for ecosystem health and management. Recent technological advances can assist in developing criteria, including structural analyses of seafloor communities potentially impacted by fishing gears (e.g. demersal trawling). Similarly, advances in fishing gear technology, including improved selectivity and the development of gears which have a more benign environmental impact, can mitigate some of the ecological impacts of fishing. Such technological advances are summarized in the context of contemporary fisheries management.     

Exotic species,fisheries and conservation of freshwater biodiversity in tropical Asia: the case of the Sepik River,Papua New Guinea

1. Development of effective conservation strategies for freshwater biodiversity must take account of the trade‐off between species preservation and human use of ecosystem goods and services. The latter cannot be prevented, and attempts to manage ecosystems that focus solely on maximizing biodiversity will fail. 2. A compromise position of management for ecosystem functioning and human livelihoods — rather than preservation of every species — will provide a better basis for biodiversity conservation. This has implications for the management of exotic species. 3. There are some situations, in lentic habitats in Sri Lanka, for example, where the establishment of exotics has increased fishery yields without apparent detriment to native biodiversity. The Sepik River in Papua New Guinea provides another illustration of potential compromises between human livelihoods and biodiversity conservation. 4. The Sepik supports a relatively unproductive fishery. Two fish stocking projects (in 1987–93 and 1993–97), representing a partnership between the Papua New Guinea Government and the United Nations (UNDP/FAO), led to the introduction of a suite of exotic fish into the Sepik. Species were selected on the basis of their potential to occupy niches not filled by native fish. Unfortunately, the outcomes of these introductions are poorly documented, although there is preliminary evidence both of increased human use of exotic fish as well as declines of some native species associated with the spread of exotics. 5. Better understanding of the results of the Sepik fish introductions is important, because the pressures of burgeoning human populations in most of tropical Asia make it impossible to preserve near‐pristine environments such as the Sepik. While attempts to conserve natural or near‐natural systems must remain a priority, there is a need to develop strategies for the management of damaged or degraded ecosystems, which may contain exotics, with the aim of maintaining ecosystem functioning and, if possible, maximizing the persistence of native biodiversity. Copyright © 2006 John Wiley & Sons, Ltd.     

海洋与水产相关学科SCI源期刊信息库

以表格的形式按期刊评价指标排序的方法，介绍了以２１３种期刊构成的《海洋与水产相关学科ＳＣＩ源期刊信息库》，该信息库的ＳＣＩ源期刊代表了海洋与水产学科最核心的科技期刊，对广大科研人员向世界宣传自己的学术成果，展示我国的科研实力，将起到重要的参考作用。     

Global Advances in Conservation and Management of Marine Ornamental Resources

Currently, as many as 30 million coral reef fish belonging to 1,000 species are collected annually to supply private and public aquaria around the world. In addition, over 100 species of invertebrate are used, involving hundreds of thousands or even millions of individuals. The majority of these specimens come from coral reefs and associated habitats, with about 45 countries supplying the ornamental market. Considering the many pressures currently faced by reefs it is vital that ornamental fisheries are investigated and monitored, and management strategies formulated to ensure they are sustainable. This requires research, monitoring, training, use of non-damaging collecting methods and adoption of conservation strategies for controlling catch, such as reserves, quotas and closed seasons. There are also a number of possibilities for enhancing the fishery, such as mariculture and construction of artificial reefs. This paper concentrates on some of the conservation measures that can be taken and discusses their application and effectiveness. Such measures include limiting collecting effort, establishment of species-based or overall quotas, restrictions on rare and/or endemic species, temporary closures and establishment of fisherybreak reserves.     

Spatially explicit fisheries simulation models for policy evaluation

This paper deals with the design of modelling tools suitable for investigating the consequences of alternative policies on the dynamics of resources and fisheries, such as the evaluation of marine protected areas (MPA). We first review the numerous models that have been developed for this purpose, and compare them from several standpoints: population modelling, exploitation modelling and management measure modelling. We then present a generic fisheries simulation model, Integration of Spatial Information for FISHeries simulation (ISIS‐Fish). This spatially explicit model allows quantitative policy screening for fisheries with mixed‐species harvests. It may be used to investigate the effects of combined management scenarios including a variety of policies: total allowable catch (TAC), licenses, gear restrictions, MPA, etc. Fisher's response to management may be accounted for by means of decision rules conditioned on population and exploitation parameters. An application to a simple example illustrates the relevance of this kind of tool for policy screening, particularly in the case of mixed fisheries. Finally, the reviewed models and ISIS‐Fish are discussed and confronted in the light of the underlying assumptions and model objectives. In the light of this discussion, we identify desirable features for fisheries simulation models aimed at policy evaluation, and particularly MPA evaluation.     

Relationships among long'term fisheries abundances, hydrographic variables, and gross pollution indicators in northeastern U.S. estuaries

Categorical time series regression was applied to 55 fish stocks in the Potomac, Hudson, Narragansett, Delaware, and Connecticut estuaries for the period 1929–1975. Interannual variability in catch per unit effort (CPUE) was related to CPUE, hydrographic variables, and pollution variables, lagged back in time to represent the conditions contributing to the multiple ages comprising each fishery. Hydrographic variables included water temperature and flow in the estuary– and, for offshore spawning stocks, wind direction and magnitude–during the months of spawning and early life stage development. Pollution variables included measures of dissolved oxygen conditions in the estuaries, volume of material dredged, and sewage loading (or human population). Lagged CPUE, hydrographic variables, and pollution variables all played important roles in explaining historical variability in CPUE. Lagged CPUE was significant in 45 of 55 stocks generally accounting for 5–35% of the variability. Lagged hydrographic variables were significant in 53 of 55 stocks, explaining an additional 5–40% of the variability unaccounted for by lagged CPUE. Lagged pollution variables were significant in 35 of 55 stocks, generally accounting for an additional 5–30% of the variability not explained by lagged CPUE and hydrographic variables. Results did not exhibit expected patterns of consistency in the importance of lagged CPUE for a species across estuaries or consistency in the importance of pollution variables across estuaries. Results did exhibit the expected north-to-south longitudinal pattern in the importance of timing of the hydrographic variables, the months of importance being one or two months later in more northerly estuaries. Higher-order interaction effects were important in almost all stocks that were well-modeled by categorical time series regression. Of the 30 stocks with final regression models having R² > 0.55, 26 stocks involved significant interaction effects, five had only significant interaction effects (no significant main effects), and 20 stocks had significant interactions involving variables not significant as main effects. The difficulties involved in analyzing long-term trends in fish populations and partitioning variability between natural and anthropogenic sources are discussed.