A framework for adaptive gear and ecosystem‐based management in the artisanal coral reef fishery of Papua New Guinea

• 1. Artisanal fishing on coral reefs in Papua New Guinea is an important livelihood activity that is managed primarily at the level of local communities. Pockets of overexploitation exist and are expected to increase with plans for increased commercialization.
• 2. This paper provides a current assessment of the artisanal multi‐species coral reef fishery by examining selectivity of the dominant gear, namely line fishing, spearguns, and gill nets. Each gear has its own strengths and weaknesses in terms of use and conservation of resources, with no clear problem gear.
• 3. The three gears utilize different resources but there was moderate overlap in the species caught, particularly between gill nets and line fishing and marginally between lines and spearguns. Gill nets have the disadvantage of being destructive to coral and the advantage of catching commercial species. Line fishing catches an intermediate number of species but mostly large‐bodied and predatory species that could potentially reduce predation and the mean trophic level of the fishery. Spearguns catch the highest numbers of species, including many non‐commercial and herbivorous fish and could reduce the diversity of fish and encourage algal growth.
• 4. This information could be used in combination with scientific monitoring and traditional ecological knowledge to develop an adaptive management framework that uses local restrictions on the various gears to restore or balance the fishery and ecosystem. Restrictions could be selectively imposed: on gill nets when coral cover is low, line fishing when large‐bodied predators are depleted, and spearguns when biodiversity is reduced and algal abundance high.

Copyright © 2008 John Wiley & Sons, Ltd.     

Spatial and temporal diversity of fish captured by light traps in various habitats in coastal waters in the oldest marine protected area in Vietnam and its implications for conservation

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Ecological indicators for coral reef fisheries management

Coral reef fisheries are of great importance both economically and for food security, but many reefs are showing evidence of overfishing, with significant ecosystem‐level consequences for reef condition. In response, ecological indicators have been developed to assess the state of reef fisheries and their broader ecosystem‐level impacts. To date, use of fisheries indicators for coral reefs has been rather piecemeal, with no overarching understanding of their performance with respect to highlighting fishing effects. Here, we provide a review of multispecies fishery‐independent indicators used to evaluate fishing impacts on coral reefs. We investigate the consistency with which indicators highlight fishing effects on coral reefs. We then address questions of statistical power and uncertainty, type of fishing gradient, scale of analysis, the influence of other variables and the need for more work to set reference points for empirical, fisheries‐independent indicators on coral reefs. Our review provides knowledge that will help underpin the assessment of the ecological effects of fishing, offering essential support for the development and implementation of coral reef fisheries management plans.     

Sea cucumbers in the Seychelles: effects of marine protected areas on high‐value species

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海洋施肥及其在南海外海渔业开发方面的应用前景

海洋施肥系采取人工措施向海洋上层提供氮、磷、铁等限制性营养元素以增加海洋初级生产力的行为,其在增殖生物资源和减缓气候变化方面均具潜力。海洋施肥研究已有20年历史,但国内尚无此类研究。本文介绍了海洋微量元素铁和大营养元素氮、磷施肥的概念和基本原理,回顾海洋施肥研究发展历程,总结现有研究成果,并简要评述海洋施肥技术在应用方面存在的争议。在此基础上,着重探讨海洋施肥在南海外海渔业开发方面的应用前景。南海光热充足,但外海表层水体大营养元素匮乏,生物生产力低下,大营养元素施肥可提高海域初级生产力,从而可持续地增加渔业产量;施肥促进浮游植物繁殖而在特定海域形成的饵料生物密集区会吸引鱼群聚集,从而提高外海渔业捕捞效率。南海北部近海渔业资源已过度利用,在继续控制捕捞渔船数量和功率的情况下,开发外海施肥的渔业资源增殖技术有助于部分转移近海捕捞压力,为近海渔业的恢复性增长创造条件。     

Lessons from the past: the collapse of Jamaican coral reefs

Since Pre-Columbian times, humans have exploited Jamaican marine ecosystems with significant consequences for flora and fauna. This study focuses on the history of reef fish exploitation in Jamaica, from first human occupation to the present day, to determine how past fishing activities contributed to subsequent declines in the coral reef ecosystem. The pattern of declining reef fish populations was nonlinear. Reef fish first declined in prehistoric times but then potentially recovered, following genocide of the native human population. Reduced fishing pressure lasted until the mid-19th century. At that time, depletion of reef fish populations again occurred with a precipitous decline from the 1850s to the 1940s. The final shift from relatively abundant to overfished marine fauna corresponded to subtle changes in fish trap design as well as development of recreational fishing. Government subsidies throughout the second half of the 20th century exacerbated the declines. This analysis shows that local artisanal fisheries with relatively low levels of effort and seemingly subtle shifts in technology can significantly impact the coral reef ecosystem and that declines occurred decades to centuries before modern ecological studies began. This research shows how historical analysis can be a powerful tool to minimize shifted baselines and establish realistic targets for recovery and sustainable management of marine ecosystems.     

Understanding fishing and conservation of the Pacific seahorse (Hippocampus ingens) in Sinaloa,Mexico, through local ecological knowledge

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Ontogenetic movements of juvenile blacktip reef sharks: evidence of dispersal and connectivity between coastal habitats and coral reefs

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Fishers' experiences and perceptions of marine mammals in the South China Sea: Insights for improving community‐based conservation

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Freshwater management policies in New Zealand

1. This paper examines the effectiveness of New Zealand's Resource Management Act in managing freshwater resources. 2. A distinctive feature of the New Zealand situation is the extent to which Parliament has delegated the sustainable management of freshwater resources to catchment based regional councils. Regional councils exercise a pivotal role in water resource planning but without much guidance or technical assistance from central government. 3. Contrary to New Zealand's ‘clean green’ image, water pollution is alarmingly high in relation to its small population size. The Act puts particular emphasis on improving water quality by empowering regional councils to address this concern in policy statements and plans. 4. Water allocation policies in New Zealand are dominated by a supply-oriented biophysical perspective based on prescribing minimum flows and maximum extraction thresholds to safeguard the life-supporting capacity of ecosystems. Despite persistent attempts by central government to encourage regional councils to adopt competitive tendering and tradable permits for allocating water, most regional councils favour allocation procedures based on community consultation and political compromise. 5. Water Conservation Orders are a special provision in the Act for protecting outstanding amenity or intrinsic values of waters in their natural state. However, no new applications have been made under the RMA since 1991. 6. The RMA has brought about significant procedural improvements in water resource planning, by means of a cooperative, consultative approach. However, limited attention has been given to issues of water allocation to promote the sustainable use of increasingly scarce resources. The policies and rules in recently notified plans now regulate point source as well as non-point source discharges. Nevertheless, central government may need to reassess its role if it wishes to achieve a significant improvement in water quality and there needs to be greater coordination of water resource monitoring systems operated by regional councils to provide a national overview. ©1997 John Wiley & Sons, Ltd.     

A role for partially protected areas on coral reefs: maintaining fish diversity?

• 1. Completely banning fishing from coral reefs is now accepted to have significant benefits for marine biodiversity and in many cases, fisheries. However, the benefits of regulating fishing on coral reefs, by restricting the methods used, or the total amount of fishing, are less well understood, even though such regulations are much more likely to be supported by fishermen.
• 2. This study assesses whether banning illegal, destructive fishing methods and reducing the numbers of fishermen visiting from outside an area benefits a coral reef fishery, despite unregulated fishing by local fishermen using non‐destructive methods.
• 3. The abundance, biomass, mean length, and species richness of nine commercially important fish families are compared across ten independent patch reefs inside and outside the 470 km² Menai Bay Conservation Area in Zanzibar, Tanzania.
• 4. Even after taking into account the effect of differences in habitat and the distance between reefs, 61% (±19.7%) more fish species were found in regulated than unregulated reefs. Fish abundance, biomass, and length were not affected, suggesting that banning destructive fishing may improve biodiversity, but that further regulations may be required to improve fish stocks.Copyright © 2011 John Wiley & Sons, Ltd.

     

Biodiversity value of a geographically restricted soft coral species within a temperate estuary

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Ridge to reef modelling for use within land–sea planning under data‐limited conditions

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Tracking the Trade in Ornamental Coral Reef Organisms: The Importance of CITES and its Limitations

The extraction of coral reef organisms for the aquarium and curio trade is reported to be contributing to coral reef degradation. The total international trade and associated impacts are unknown, because data are collected only for organisms listed on Appendix II of CITES, which include stony corals, antipatharians and giant clams. CITES data indicate that trade in live stony coral and reef substrate (live rock) increased by 15–30% each year during the 1990s, with most exports since 1992 from Indonesia and Fiji. Overall, 19% of all stony coral traded (by item) from 1985 to 1997 was live; 71kern-1pt% of this was traded between 1993 and 1997 (52% of total trade). Although tracking trade using information from the CITES Trade Database provides limited information (e.g., coral is reported to genus, and volume is reported by item or weight), the CITES mechanism promotes the development of strategies to protect resources. In response to CITES requirements, Indonesia developed a management plan for sustainable harvest of corals, but not for non-CITES listed species such as soft corals and fishes. Trade in hard and soft coral provides revenue for developing countries; however, in order to be of lasting value the industry must be developed with a conservation ethic. This requires support for international programs such as CITES, management plans for sustainable harvest, and improved enforcement.     

Evaluating impacts of fishing on benthic habitats: A risk assessment framework applied to Australian fisheries

Ecosystem-based management (EBM), in the context of fishing, considers impacts on all parts of an exploited marine ecosystem. Understanding the impacts of fishing on habitats is a necessary part of adopting EBM, but multi-scale data that describe the types and distributions of habitats, and the interactions of fishing with them, are typically limited or entirely lacking. An approach developed to address habitat impacts, and applied to all offshore bottom contact fisheries in Australian waters, forms part of a hierarchical risk assessment framework - the Ecological Risk Assessment for the Effects of Fishing (ERAEF). Its progressively quantitative hierarchical approach enables higher-risk interactions to be identified and prioritised in the early and intermediate assessment stages by screening out lower-risk interactions. The approach makes the best use of all available data, but it can also be inferential where data are lacking. At the intermediate level of the ERAEF, a semi-quantitative approach uses a general conceptual model of how fishing impacts on ecological systems, with a focus at the level of regional sub-fisheries defined by fishing method (gear type). A set of quantifiable attributes for habitats are used to describe the ‘susceptibility’ of each habitat to damage that may be caused by specific fishing gears; resilience is generalised as a habitat's inherent ‘productivity’ (ability to recover from damage). In the ERAEF, photographic imagery was used effectively to provide a standardised method to classify habitats, to visualise the attributes assessed, and to communicate with stakeholders. The application of the ERAEF to habitats is illustrated using results from a multi-sector fishery off southern Australia that has five primary sub-fisheries: two bottom trawl (‘otter trawler’ or ‘dragger’), bottom set auto-longline, bottom set gill net, and Danish seine. In the case of the otter trawl sub-fishery, a set of 158 habitat types was considered, of which 46, mostly on the outer continental shelf and slope, were identified as potentially higher risk and deserving management attention. Strengths of the ERAEF approach for benthic habitats include methodological flexibility and wide applicability, and in being interactive and inclusive - bringing stakeholders, scientists and managers together to ‘put habitat on the radar’ and to develop management solutions. Limitations include difficulties in construction and validation of scored attributes and scale dependence. In the context of ecological risk management, this method offers a way to assess risks to marine habitats in a rigorous, transparent, and repeatable manner.     

Fish conservation in freshwater and marine realms: status,threats and management

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Illegal ingegno fishery and conservation of deep red coral banks in the Sicily Channel (Mediterranean Sea)

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基于Stella的江苏近海海域生态足迹模拟分析

为了量化人类活动对海洋渔业资源可持续利用干扰的程度,本研究基于渔业生态足迹的算法,对江苏近海1978―2014年的生态足迹进行计算,研究江苏省的渔业生态现状。在此基础上,依据系统动力学(System Dynamics,SD)原理,嵌入营养动态模式,构建了江苏近海海域渔业生态足迹SD模型。利用2006―2014年的历史渔业数据验证该模型是可行的,并运用模型预测了不同捕捞强度下江苏近海渔业生态系统的发展模式。结果表明:1978―2014年江苏近海渔业生态足迹由2.41×10~6 hm~2增长到6.61×10~6 hm~2,平均值为5.38×10~6 hm~2,已经高于生态承载力3.45×10~6 hm~2,约为承载力的1.5倍,表明江苏近海海域渔业生态资源已处于不可持续的发展状态中;根据模型仿真分析,如果进一步加强捕捞强度,渔业生态足迹会急剧下降,最终趋于0值,且随着加强程度的增大,生态足迹下降越快,趋于0值的时间也越短;根据海洋渔获量阈值的计算结果,需要在目前捕捞强度基础上降低约50%,渔业生态足迹才能回升,生态赤字也能平稳降低,从而防止渔业生态系统崩溃。该研究结果可为江苏省可持续发展决策提供有益参考,也可用于江苏近海海域生态效应的预警。     

Habitat mapping in the Caribbean for management and conservation: Use and assessment of aerial photography

• 1 The nature and distribution of the coastal and shallow marine habitats of Anguilla in the Caribbean were examined using aerial photography coupled with extensive ground truth information.
• 2 The objective was to develop an accurate method of marine habitat mapping for the analysis of the marine ecosystem in order to develop a procedure for marine and coastal resource management.
• 3 This paper describes the method which was adopted as well as the biological results.
• 4 It is concluded that the management and sustainable use of the natural resources may be improved as a result of accurate habitat mapping.

     

Loggerhead turtle (Caretta caretta) bycatch in Canadian pelagic longline fisheries: Relative importance in the western North Atlantic and opportunities for mitigation

Little is known about the ecology of loggerhead turtles, Caretta caretta, in Canadian waters. However, Canada's eastern waters off the Scotian Shelf, Georges Bank and Grand Banks appear to be seasonal foraging habitats based on dates and locations where they have been captured as fishery bycatch. Estimates derived from data recorded by the international observer program (IOP) and used for this study suggest that thousands of mostly immature loggerheads have been captured in the Canadian pelagic longline fishery (PLF) in the western North Atlantic since 1999. These data suggest that the PLFs for tuna and swordfish are among the most important causes of incidental capture. Although U.S. and Canadian bycatch estimation methods differ and uncertainty associated with the estimates is high, it is clear from the IOP data that bycatch in the Canadian PLF is substantial and roughly within the same magnitude as that reported for the entire U.S. fleet in the North Atlantic for the same period (1999–2005). Analysis of bycatch observer data from the Canadian PLF and other empirical data suggests that fishing at temperatures below 20 °C using fish rather than squid bait and size-18 circle hooks could reduce loggerhead bycatch and mortality. However, research is needed to identify the best options and their commercial viability. Loggerheads that use Canadian Maritime waters are one of the least studied groups of loggerheads in the world, so systematic long-term studies on the ecology of loggerheads in Canada would help fill important information gaps and assist in developing effective recovery plans for this species.