Social indicators of vulnerability for fishing communities in the Northern Gulf of California,Mexico: Implications for climate change

Marine fisheries support the livelihoods of millions of people worldwide. These fisheries and the communities that depend on them are highly vulnerable to climate change and other interacting anthropogenic threats. The cumulative and interacting effects of these stressors could potentially produce declines in fish production, which would significantly impact artisanal fishers. Assessing relative vulnerability of fishing communities to anthropogenic stressors is an important first step to identifying mitigation or adaptation strategies. This study assessed the vulnerability of 12 coastal communities in the Northern Gulf of California to disruptions in fishing activities from anthropogenic stressors, including climate change. The Northern Gulf is a megadiverse area and a major source of fishery resources. Quantitative indicator indices based on secondary and primary data were developed to assess the three aspects of vulnerability: sensitivity, exposure, and adaptive capacity. The key components of vulnerability varied amongst communities. Vulnerability was higher in communities with higher fishing dependence and lower socioeconomic diversification. The approach presented here provides important insights into the type of policy actions that might be needed in different communities for adaptation and mitigation.     

Forecasting the consequences of climate-driven shifts in human behavior on cetaceans

While climate change is expected to affect cetaceans primarily via loss of habitat and changes in prey availability, additional consequences may result from climate-driven shifts in human behaviors and economic activities. For example, increases in shipping, oil and gas exploration and fishing due to the loss of Arctic sea ice are highly likely to exacerbate acoustic disturbance, ship strikes, bycatch and prey depletion for Arctic cetaceans. In the tropics, climate change may result in increased hunting pressure on near-shore dolphins and whales off Asia, Latin America, Africa, and elsewhere as the availability of other marine resources diminishes. This study explores the range of potential consequences to cetaceans worldwide from predicted climate-driven shifts in human behavior, and evaluates the risks to particular species given their geographic ranges and habitat preferences. While concern about impacts of climate change on cetaceans has largely focused on polar species, the analysis presented here suggests tropical coastal and riverine cetaceans such as the Irawaddy dolphin, Indo-Pacific humpback dolphin, and finless porpoise are particularly vulnerable to those aspects of climate change that are mediated by changes in human behavior. Policy recommendations include the following: (1) information about cetacean populations should be incorporated into national, regional and international climate adaptation decisions wherever possible (for example, via GEF-sponsored adaptation initiatives); and (2) human-mediated impacts of climate change should be included in cetacean conservation and management plans, such as the management procedures of the International Whaling Commission (IWC), where possible. Because human responses to climate change are likely to evolve rapidly over the coming years and decades, it is important that local, regional and international cetacean conservation and management plans include regular reviews to allow them to adapt to new information.     

海岸带脆弱性评估方法研究进展

海岸带脆弱性源于气候变化、海平面上升、人类活动的共同作用,而海岸带脆弱性评估的误差主要是来自海岸环境演化预案和社会经济发展预案的不确定性。为了提高评估精度,应确定海岸系统内、外部驱动力及其关键变量,研究自然和人类活动共同作用下的海岸系统演化过程、海岸系统风险发生的机制、以及海岸系统承载力和阈值,通过遥感和地理信息系统技术集成,建立适用的预案,用于脆弱性综合评估。     

Impacts of trawling on benthic macro-fauna and -flora of the Spencer Gulf prawn fishing grounds

The overall effects of trawling on benthic habitats and their assemblages are dependent on the distribution and intensity of trawl effort. The benthic habitats of the Spencer Gulf prawn trawling grounds are subjected to known variable levels of trawling disturbance recorded from fisher's logbooks. These habitats have not been quantitatively investigated. The aim of the study was firstly to characterise the macro-faunal and -floral assemblages and secondly, to comparatively assess trawl impact by testing the null hypothesis of no differences between five sites exposed to different intensity of trawl effort. The distribution and abundance of benthic macro-fauna and -flora were studied at two sampling resolutions by using beam trawl sampling (10,000 m²) and underwater stereophotography (4.5 m²) at five sites with different levels of trawl disturbance (effort). The results showed that the Spencer Gulf prawn trawling grounds are characterised by sandy sediments with a low content of silt and clay, with the exception of one site with very fine gravel. Biomass, abundance and cover of macro-fauna and -flora were generally low throughout, but with large differences among sites. Biomass, abundance and cover were found to be negatively correlated to both trawl hours from 1994–1998 and during the period of study. ANOSIM and SIMPER analyses using biomass, abundance and percentage cover as variables showed significant differences between sites with eight species or taxonomic groups contributing more than 10% to the observed similarity within sites. The two northern sites were dominated by sponges and the bearded mussel, Trichomya hirsutus, and the southern hammer oyster, Malleus meridianus. Other species that contributed to the similarity within sites were the ascidian, Polycarpa viridis, mobile epifauna (the blue swimmer crab, Portunus pelagicus, and the western king prawn, Penaeus (Melicertus) latisulcatus) and demersal fish species (Degens leatherjacket, Thamnaconus degeni, and the Melbourne silver belly, Parequula melbournensis). Simpson's Index of Diversity (1 − λ) and species richness in the beam trawl samples were fairly even across all sites, but a significant effect of site was found in the stereophotographic transect samples. It was concluded that prawn trawling has a strong influence on the structure of the benthic habitats of the Spencer Gulf prawn fishing grounds highlighted by the magnitude of change and the strength of the gradient of effects. Confounding factors linked to the biophysical attributes of the sites are believed to be minor.     

A broad-scale assessment of the risk to coastal seagrasses from cumulative threats

Informing the management of coastal marine habitats at broad spatial scales is difficult because of the costs associated with collecting and analyzing ecological data at that scale. Spatially explicit assessments of the risk to coastal marine habitats from cumulative threats provide an alternative approach by identifying sites that are exposed to multiple anthropogenic threats at broad scales. In this study, qualitative measures of vulnerability were combined with geospatial data to evaluate the risk to coastal seagrasses at the scale of the Great Barrier Reef (GBR) region (∼26,000 km²) of Queensland, Australia. The risk assessment outputs identified agricultural, urban and industrial runoff, and urban and port developments as the major anthropogenic activities threatening coastal seagrasses. ‘Hot spots’ with multiple threat exposure were all in industrial port locations and the southern two-thirds of the GBR. There is a distinct discontinuity in threat exposure along the GBR coast with 98% of seagrass meadows in the northern third exposed to only low levels of anthropogenic risk. The clustering of threat exposure is discussed in terms of coastal management policy. The approach outlined in this study provides management agencies a method of achieving maximum return for minimal investment in data collection at broad spatial scales by identifying sites where management intervention would be best targeted.     

Securing ocean benefits for society in the face of climate change

Benefits humans rely on from the ocean – marine ecosystem services – are increasingly vulnerable under future climate. This paper reviews how three valued services have, and will continue to, shift under climate change: (1) capture fisheries, (2) food from aquaculture, and (3) protection from coastal hazards such as storms and sea-level rise. Climate adaptation planning is just beginning for fisheries, aquaculture production, and risk mitigation for coastal erosion and inundation. A few examples are highlighted, showing the promise of considering multiple ecosystem services in developing approaches to adapt to sea-level rise, ocean acidification, and rising sea temperatures.Ecosystem-based adaptation in fisheries and along coastlines and changes in aquaculture practices can improve resilience of species and habitats to future environmental challenges. Opportunities to use market incentives – such as compensation for services or nutrient trading schemes – are relatively untested in marine systems. Relocation of communities in response to rising sea levels illustrates the urgent need to manage human activities and investments in ecosystems to provide a sustainable flow of benefits in the face of future climate change.     

捕捞和气候变化在南海北部湾口鱼类长期种类演替和种群动态的作用

捕捞压力在改变南海鱼类种类演替和生物量波动方面所起的作用大于气候和环境因素是一个普遍的、有争议的假设。根据1959~2010年南海北部北部湾口底拖网的调查数据,报告了该海域鱼类种类组成、优势类群的丰度比例、生物量的季节和年际变化。建立了鱼类生物量与捕捞压力和气候变化外部因素之间的广义加性模型。结果表明,捕捞压力驱动底层渔业资源急剧下降的主要因素,并随着时间的推移,高值鱼类被低值鱼类所取代。1993年和1998年期间鱼类生物量的突然减少与同期厄尔尼诺事件相对应,气候变化可能是渔业拖网捕捞中中上层鱼类比例变化的主要驱动因素。为了更好地了解鱼类群落动态,需要区分捕捞压力和环境驱动因素对不同生活史策略鱼类物种的影响。     

Snapper (Chrysophrys auratus): a review of life history and key vulnerabilities in New Zealand

Snapper (Chrysophrys auratus) is an important coastal fish species in New Zealand for a variety of reasons, but the large amount of research conducted on snapper has not been reviewed. Here, we review life history information and potential threats for snapper in New Zealand. We present information on snapper life history, defining stages (eggs and larvae, juvenile and adult), and assess potential threats and knowledge gaps. Overall we identify six key points: 1. post-settlement snapper are highly associated with certain estuarine habitats that are under threat from land-based stressors. This may serve as a bottleneck for snapper populations; 2. the largest knowledge gaps relate to the eggs and larvae. Additional knowledge may help to anticipate the effects of climate change, which will likely have the greatest influence on these early life stages; 3. ocean acidification, from land-based sources and from climate change, may be an important threat to larval snapper; 4. a greater understanding of population connectivity would improve certainty around the sustainability of fishery exploitation; 5. the collateral effects of fishing are likely to be relevant to fishery productivity, ecosystem integrity and enduser value; 6. our understanding of the interrelationships between snapper and other ecosystem components is still deficient.     

Building adaptive capacity to climate variability: The case of artisanal fisheries in the estuary of the Patos Lagoon,Brazil

The vulnerabilities of fishing communities to climate and environmental change represent major issues for the governance of fisheries resources which have a direct effect on human security, livelihoods and rights. This paper explores the dynamics of social-ecological systems in the estuary of the Patos Lagoon in southern Brazil. The paper identifies key factors that increase and/or minimize the vulnerabilities of the fishing communities in this lagoon with the objective of understanding: (a) the degree to which fishing communities are able to build adaptive and learning capacities to minimize/reduce vulnerabilities and maintain their livelihoods; and (b) how and under what circumstances external and internal factors may influence and disrupt the social-ecological resilience in this lagoon system. Results show that fishing communities with a higher degree of self-organization are able to create ways to minimize their vulnerability to adverse climatic conditions. However, only a few communities have developed adaptive mechanisms to cope with the influence of climate on resource abundance and availability. Little external institutional support for small-scale fishing communities, erosion of their traditional resource use systems and decreasing fish stocks in recent decades have all led to a gradual increase in the vulnerability of fishing livelihoods in this lagoon. The uncertainties associated with climate are related to increasing vulnerability and influence the degree of resource conservation and exploitation. The lack of public policies to deal with the impact of climate variability on the livelihoods of fishing communities and the presence of weak institutions in resource governance represent major threats to the social security of fishers in this region.     

Mapping Vulnerability and Risk of Ghana's Coastline to Sea Level Rise

Coastal erosion and flooding are major threats to coastal dwellers, and the situation is predicted to worsen as a result of the impacts of climate change and associated sea level rise. In order to identify the level of vulnerability of various sections of Ghana's coastline for planning and future hazard management, a coastal vulnerability index approach was adopted for the creation of the relative vulnerability map. The coastal vulnerability variables used include geomorphology, coastal elevation, geology, local subsidence, sea level rise, shoreline change rates, mean tidal range, mean wave height and population density of the coastal areas. Risk factors were assigned to the various variables, and all the factors were combined to calculate the coastal vulnerability for the coastal front of each administrative district along the coast. The outcome was used to produce a vulnerability index map of coastal districts in Ghana. The results revealed that parts of the central coast and the eastern coasts of Ghana were the most vulnerable. It was identified that about 50% of the 540km shoreline of Ghana is vulnerable. This assessment will facilitate the long-term adaptation planning and hazard mitigation to inform the management of Ghana's coast.     

The bottom line: An investigation of the economic,cultural and social costs of high seas industrial longline fishing in the Pacific and the benefits of conservation

High sea industrial longline fishing can be understood as a case study of the cultural, economic, environmental and social impacts of unsustainable fishing technology. While much attention has been attributed to the impact of industrial longlines on the marine ecosystem, little is known about the impact of longline fishing on local food security, employment, cultural belief systems and traditions, revenue generation from marine tourism and climate change. New data demonstrate that the contributions of Marine Protected Areas, marine tourism and recreational fishing to local coastal economies dwarf the contributions of longline fishing. When combined with the impact of overfishing on coastal fishing communities and fish consumers, policies promoting sustainable fisheries must be expanded to take these other factors into account along with issues of biodiversity.     

Modelling the physical impact of trawl components on the seabed and comparison with sea trials

Quantitative measurement of the response of benthic habitats to impact from towed fishing gears is of great importance to the ecosystem and the long-term management of sustainable fisheries. To date, most studies on the effects of trawling on the benthos have focussed on before/after, control/impact comparative studies. This research has proved important in terms of describing general trends and has identified taxa that suffer high levels of mortality, and habitat types where impact is the greatest. A limitation, however, to this comparative work is the lack of prediction-based methodology and it would be very beneficial to develop a more mechanistic approach that would allow trawling impact on the benthos to be estimated for a wider range of species and habitats. This paper is a first step in this approach and focuses on modelling the physical interaction between gear components and the seabed. In particular the penetration and disturbance to the seabed caused by (i) the roller clump of a twin trawl and (ii) a trawl door, are examined.A finite element (FE) model of the interaction of these components and the seabed is developed using the different soil models and features available within the Abaqus finite element software package. The resulting models are able to predict the penetration depth and sediment displacement associated with each gear component and the predictions are compared with the results obtained during sea trials. The sea trials were undertaken on two sediment types at depths accessible to scientific divers using SCUBA diving techniques who measured and profiled the physical alteration to the seabed following the passage of a roller clump and a trawl door. In addition, drag forces obtained from the sea trials are compared with numerical predictions of the drag related to the soil and the estimated fluid drag. Good agreement between the experimental trials and numerical simulations is found and hence this study provides the basis for investigation of the interaction of other components and sediment types.     

Development and application of a methodology for vulnerability assessment of climate change in coastal cities

This research is based on the need to develop methodology for climate change vulnerability assessment in coastal cities. While there have been some studies on the development of methodologies for vulnerability assessment on a national scale, there have been few attempts to develop a method for local vulnerability assessment with application to coastal cities. The objective of this study was to develop a general methodology to assess vulnerability to climate change and to apply it to the metropolitan coastal city of Busan in South Korea. We followed the conceptual framework for assessing climate change vulnerability provided by the Intergovernmental Panel on Climate Change (IPCC), which is composed of climate exposure, sensitivity, and adaptive capacity. Sea level rises of 0.5 m, 1 m, 2 m, and 3 m were considered as the climate exposure. Sensitivity to sea level rise was measured based on the percentage of flooded area calculated using flood simulation with a GIS tool. The population density and the population at age 65 years and over were also included in the calculation of sensitivity index. Sensitivities to heat wave and heavy rainstorm were quantified using the expert opinions from the Delphi survey and information on land use classification. Adaptive capacity was assessed in three sections: economic capability, infrastructure, and institutional capabilities. By combining the adaptive capacity and three different sensitivities, vulnerability to sea level rise (SLR-V), vulnerability to heavy rainstorm (HR-V), and vulnerability to heat wave (HW-V) were separately evaluated in 16 counties of Busan. Using cluster analysis, we could classify four major groups of counties based on SLR-V, HR-V, HW-V, and reported damage cost. For clustered groups, different adaptation strategies were suggested based on the different vulnerability patterns. Application of our methodology to Busan indicated that our methodology is easy to use and provides concrete policy implications when setting up adaptation strategies. The methodology developed in this study could also be used in mainstreaming climate change into Integrated Coastal Management (ICM).     

Climate change, sea level rise and integrated coastal zone management: An IPCC approach

Expansion of economic activities, urbanisation, increased resource use and population growth are continuously increasing the vulnerability of the coastal zone. This vulnerability is now further raised by the threat of climate change and accelerated sea level rise. The potentially severe impacts force policy-makers to also consider long-term planning for climate change and sea level rise. For reasons of efficiency and effectiveness this long-term planning should be integrated with existing short-term plans, thus creating an Integrated Coastal Zone Management programme.As a starting point for coastal zone management, the assessment of a country's or region's vulnerability to accelerated sea level rise is of utmost importance. The Intergovernmental Panel on Climate Change has developed a common methodology for this purpose. Studies carried out according to this Common Methodology have been compared and combined, from which general conclusions on local, regional and global vulnerability have been drawn, the latter in the form of a Global Vulnerability Assessment.In order to address the challenge of coping with climate change and accelerated sea level rise, it is essential to foresee the possible impacts, and to take precautionary action. Because of the long lead times needed for creating the required technical and institutional infrastructures, such action should be taken in the short term. Furthermore, it should be part of a broader coastal zone management and planning context. This will require a holistic view, shared by the different institutional levels that exist, along which different needs and interests should be balanced.     

黄海夏季不同取样网具渔获物组成比较分析

根据 2 0 0 0年夏季双拖渔船和“北斗”号专业调查船对应站位拖网调查资料 ,进行了两种不同取样网具情况下渔获物组成的比较分析 ,结果表明 :渔船的单位扫海面积渔获量、几种重要种类的长度范围、平均个体长度、5 0 %选择长度、重量计优势度均高于“北斗”号 ,而渔获种类数则少于“北斗”号 ,且两者种类组成相似性较低 ,仅为 0 .4 5 8;而且“北斗”号的底层、近底层鱼类和无脊椎类占总渔获量的比例高于渔船 ,这主要是由于渔具的选择作用造成的。结果说明应用渔船针对渔业生产进行的渔业资源监测 ,对带鱼、小黄鱼、鱼等重要生产种类是适合的 ,能够反映其资源量状况 ,但对群落结构、生物多样性等生态系统水平上的研究却存在着明显的不足     

Identifying drivers for fishing pressure. A multidisciplinary study of trawl and sea snail fisheries in Samsun,Black Sea coast of Turkey

This study aims to investigate and model driving forces that lead to increased fishing pressure and an altered state of the environment in the coastal areas near Samsun on the Turkish Black Sea coast. We have applied a modified DPSIR model to structure our investigation and analysis and have investigated the drivers that generate fishing pressure in the Samsun fisheries. The overall health of the ecosystem is declining, and there is a consistent trend of deterioration in the condition of the three major species targeted by the trawl fisheries. Although introduced invasive species have brought significant changes to the Black Sea, it is clear that the state of the environment is significantly and negatively affected by the pressure exerted by fisheries. Fishing pressure has to a certain extent been redirected to pelagic trawling as bottom trawling has become less profitable and a rise in catch capacity has levelled off. This reduction is, however, offset by an increase in illegal trawling and dredging by a very rapidly growing sector of multi-purpose small boats, resulting in a considerable increase in the overall accumulated engine power of fishing boats in Samsun during 2000–2005. Fisheries in Samsun, in particular sea snail fisheries, have constituted a frontier of sorts open to the poorer populations of Samsun during the last 20 years, and, thereby, constitute one of the major drivers for fishing pressure. We identify eight drivers of importance for the period 2000–2005. Although the authorities can impact all or most of those drivers, most of them are beyond the scope of conventional ‘fisheries management’.     

Whether human-induced activities could change the gradient pattern of coastal land use along the sea-land direction: a case study in Manila Bay,Philippines

Increasing intense human activities have largely changed the coastal landscape and caused many environmental issues. However, whether human-induced activities could change the coastal land use gradient pattern, an important coastal zonal characteristic along the sea–land direction, remains unclear. Manila Bay was selected as the study area in this work. According to the distance of the land use and land cover(LULC) to the coastline, we clustered the typical coastal land use sequence patterns(CLU...     

Abundance of the Indo-Pacific bottlenose dolphin Tursiops aduncus off south-west Mauritius

The abundance of Indo-Pacific bottlenose dolphins Tursiops aduncus off the south-west coast of Mauritius was estimated using capture-mark-recapture modelling. Over the past two decades this population has been subjected to ongoing anthropogenic disturbance in the form of extensive coastal development. Furthermore, daily dolphin tourism, which started in 1998, has rapidly increased in intensity. Identification photographs were collected between April 2008 and June 2010 from dolphins occurring along a 30 km length of coast where a dolphin tourism industry is concentrated. A total of 137 groups were encountered over 229 survey days. Over 5 000 photographs were taken, from which 35 individuals were considered to be sufficiently distinctively marked to use in mark-recapture analyses. The majority (85.7%) were seen more than once and resighting frequencies indicated a resident population. Three newborn calves were recorded during the study. Open population models produced abundance estimates of <100 individuals in the population. These results will be used to make recommendations for the conservation and management of this small, resident population, which is a valuable economic resource for the island but is currently under threat from high levels of human activity.     

The influence of weather on the recreational uses of coastal lagoons in Rhode Island,USA

The recreational uses of coastal lagoons (also known locally as salt ponds) contribute significantly to the important tourism economy of the southern part of the US state of Rhode Island. The lagoons are valued highly for the wide range of recreational services they provide, such as fishing, clamming, rowing, boating, or merely relaxing. Outdoors on or near the water, weather conditions may influence individual recreation decisions strongly. A changing climate is expected to affect weather conditions in Rhode Island, thereby potentially influencing when, how, and how much recreation will take place in the coastal areas of the state. Through direct observations of human activities on coastal lagoons, the sensitivity of coastal recreational uses to changes in weather conditions was assessed. If future changes in climate bring warmer temperatures and more intense wind and rain events, our results suggest that there may be a decrease in relaxing, rowing, and fishing on coastal lagoons when days are hotter and a decrease in rowing and fishing when days are windier. Nevertheless, warmer temperatures also may lengthen the summers, leading to an overall increase in the peak coastal recreation season. However, during the hottest periods, there may be a shift toward more motor boating and away from other uses, motor boaters were more resistant than other users to changes when temperatures increase. Understanding how weather and climate influence coastal recreation could help coastal managers and businesses better plan for the future in Rhode Island and other coastal environments worldwide.     

Spatial overlap of Black-browed albatrosses with longline and trawl fisheries in the Patagonian Shelf during the non-breeding season

Incidental mortality in fisheries is the main at-sea threat albatrosses are facing nowadays. In this study we used remote sensing techniques to model the degree of spatial overlapping between the Black-browed albatross (Thalassarche melanophris) and Argentine fisheries, assuming this as a proxy of risk for albatrosses. Eleven tags were deployed on albatrosses during the non-breeding seasons 2011 and 2012 in the Patagonian Shelf. Their distribution overlapped to different extents with the two coastal trawl, three offshore trawl and one demersal longline fisheries. The overlap index showed highest values with both coastal fleets, followed by the ice-chilling trawl fleet. These intersections were located in the Argentinean–Uruguayan Common Fishing Zone, in coastal areas of the SE of Buenos Aires province, El Rincón estuary and over the shelf break. The analysis of intersections of focal areas from albatrosses and all fisheries allowed the identification of thirty-four fishing management units (1° by 1° grid within the Argentine EEZ) classified as of medium, high or very high conservation priority. Very high priority units were placed between 35 and 38°S in the external mouth of Rio de la Plata, and between 45 and 47°S in neighboring waters East to the hake fishing closure. Although there were possible biases due to the limited number of tracked birds and the locations where albatrosses were captured and instrumented, the information presented in this study provides a comprehensive picture of important areas of overlapping during winter that could be used by the fishery administration to prioritize conservation actions under limited resource scenarios.