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With much fanfare, Ghana's Jubilee Oil Field was discovered in 2007 and began producing oil in 2010. In the six coastal districts nearest the offshore fields, expectations of oil-backed development have been raised. However, there is growing concern over what locals perceive to be negative impacts of oil and gas production. Based on field research conducted in 2010 and 2015 in the same communities in each district, this paper presents a longitudinal study of the impacts (real and perceived) of oil and gas production in Ghana. With few identifiable benefits beyond corporate social responsibility projects often disconnected from local development priorities, communities are growing angrier at their loss of livelihoods, increased social ills and dispossession from land and ocean. Assuming that others must be benefiting from the petroleum resources being extracted near their communities, there is growing frustration. High expectations, real and perceived grievances, and increasing social fragmentation threaten to lead to conflict and underdevelopment.
The use of local knowledge observations to generate empirical wildlife resource exploitation data in data-poor, capacity-limited settings is increasing. Yet, there are few studies quantitatively examining their relationship with those made by researchers or natural resource managers. We present a case study comparing intra-annual patterns in effort and mobulid ray (Mobula spp.) catches derived from local knowledge and fisheries landings data at identical spatiotemporal scales in Zanzibar (Tanzania). The Bland–Altman approach to method comparison was used to quantify agreement, bias and precision between methods. Observations from the local knowledge of fishers and those led by researchers showed significant evidence of agreement, demonstrating the potential for local knowledge to act as a proxy, or complement, for researcher-led methods in assessing intra-annual patterns of wildlife resource exploitation. However, there was evidence of bias and low precision between methods, undermining any assumptions of equivalency. Our results underline the importance of considering bias and precision between methods as opposed to simply assessing agreement, as is commonplace in the literature. This case study demonstrates the value of rigorous method comparison in informing the appropriate use of outputs from different knowledge sources, thus facilitating the sustainable management of wildlife resources and the livelihoods of those reliant upon them.
The coast of Aragua is a home of bottlenose dolphins (BND), Atlantic spotted dolphins (ASD) and fishermen (FIS) from four towns. A photo-identification study was carried out on BND to estimate their home ranges. From 2004 to 2008, 100 field surveys were carried out along 30 km of coastline (92.12 km2). In each sighting of BND, information regarding date, time, latitude/longitude and photographs were registered (ASD and FIS were registered without photography). The data were analysed using a Geographic Information System to estimate Minimum Convex Polygon (MCP) and Fixed Kernel (FK) at 95%. The home ranges of BND were estimated for seven individuals. This included three females (29–31 sightings) with estimated areas ranging from 33.90–39.90 km2 with MCP (36.79–43.31% of the study area) and from 80.47–101.31 km2 with FK (109.97–104.26%). For the remaining four dolphins (14–20 sightings) the estimated areas ranged from 9.67–22.34 km2 (MCP), the predominant depth of these home ranges varied from 51–100 m (χ2 = 24.5, df = 2, P = 4.785 × 10−6). For the pods of ASD the estimated area ranged 75.23 km2 with MCP (81.66%) and 119.86 km2 with FK (130.11%) with predominant depths of 101–200 m (χ2 = 24.5, df = 2, P = 4.785 × 10−6). The area used by FIS ranged 93.27 km2 by MCP and 228.49 km2 by FK. Finally, the overlap area of BND, ASD and FIS ranged 24.75 km2 (26.86%). We point out this locality presents important oceanographic and ecological aspects which deserve to be the subject of application of management plans for the conservation of its habitat and species.
Flow regulation and water abstraction from rivers have devastating effects on receiving lakes. The most egregious example is the Aral ‘Sea’: from the 1960s, water for irrigation was diverted from influent rivers; 40 years later, the Aral had dwindled to tiny remnants - fisheries had long since collapsed. Shrinkage of lakes and wetlands across central Asia demonstrate the consequences of expanding irrigation, and highlight conflicts among human water users. Lake Chad in Africa has virtually disappeared as a result of water mismanagement, as has Lake Poopó in Bolivia; Yangtze floodplain lakes have diminished also. All such cases have had serious consequences for migratory waterbirds. In a few instances (Mono Lake in the US, the Mesopotamian marshes), the damage caused can be partially reversed by restoring water supplies, but the causes and drivers of ecosystem degradation are particular to each lake. Even the world’s largest water body, Lake Baikal, is subject to anthropogenic insult. Here, as is typical of lakes globally, a variety of factors – most often eutrophication, land-use change and alien species – contribute to habitat degradation and declines of endemic species.
The hydrological cycle is driven by warmth from the sun, and thus climate change will influence the availability of surface water, the frequency of extreme events, and the extent and duration of aquatic habitat. In addition, most freshwater animals are ectothermic, so climate change will affect habitat quality: will it be too warm? Will species be able to shift their distributions so they can remain within their physiological tolerances? Or, will adaptation be sufficiently rapid to cope with warming? The footprint of climate change is evident after only 1°C of average atmospheric warming: almost 75% of all ecological processes investigated in fresh waters have been affected, with seasonality and distribution of many taxa shifting. Lakes are sentinel ecosystems for climate change because stratification and internal dynamics are affected by temperature, and warming has affected productivity in both Lakes Baikal and Tanganyika. Climate warming will likely favour the spread of alien species, and amplify other anthropogenic threats to biodiversity. The consequences will be most apparent in water bodies already subject to eutrophication, poor water quality, or overexploitation.
Share contracts are the dominant remuneration system in artisanal fisheries. Introducing regulations based on collective use rights may affect the way profits are distributed. The literature on the effect of regulatory reform on factor income distribution, however, is scarce. In this paper, we look at differences in the implementation of the Extractive Artisanal Regime in Chilean hake artisanal fisheries to test its effect on share contracts. We estimated a switching regression model using census data to calculate the average treatment effect. Our results show that crewmembers in communities regulated by some form of collective use rights receive, on average, 6 per cent more of total net incomes compared to those regulated by a limited access with global quota regime. Differences in the relation between crew size and labor rewards, as well as in the negotiating power of crewmembers under different regimes, may explain the results.
The SDG14 targets cover more than 70 per cent of the planet, including the coastal zone, where a range of forest resources are located. In this chapter we investigate the potential negative consequences of SDG14 on forest resources, using the example of coastal mangrove forests. SDG14 is likely to have negative impacts on forest resources because it focuses primarily on fisheries, potentially excluding other coastal natural resources. Many SDG14 targets are also more appropriate for oceanic areas, rather than the complex governance arrangements found in the coastal zone. This means that coastal forests such as mangroves may be forgotten, inadvertently impacted or fall through the ‘policy gap’ between terrestrial and marine legislation or between different levels of governance. This also has impacts on the human populations that rely on the ecosystem services provided by mangrove forests, and has implications for environmental justice. To minimise the impacts of SDG14 on mangrove forests and associated coastal communities, we recommend that SDG14 indicators should be broadened to encompass other coastal and oceanic natural resources, decentralisation of coastal zone governance should continue to be encouraged, and management regimes should include coastal communities and enshrine principles of environmental justice.
Punitive measures taken against vessels listed on RFMO IUU vessel lists often have very direct effects on the individuals associated with those vessels, such as the owner or operator. With developments such as cross-listing mechanisms and cross-references in international agreements, the number of actors that are encouraged or obliged to take measures against listed vessels now extends to a much wider group, well beyond just the Members of the listing RFMO. The impacts of these punitive measures on such individuals are accordingly very significant. Despite this, however, these listing procedures contain relatively limited due process features. This article considers whether this could contribute to diminishing the perceived legitimacy of IUU listings and generate a risk of reluctance by some actors within the international community to impose punitive measures on listed vessels.
Movement towards enhanced due process in decision-making processes appears to be emerging within many international organizations in recognition of the fact that increasingly, individuals are directly affected by decisions of international organizations. Examining such developments in other fora, this article considers possible adjustments to listing procedures, which might assist in safeguarding the legitimacy and effectiveness of IUU vessel lists. IUU lists play a significant role in international efforts to combat IUU fishing, and upholding their effectiveness is accordingly of critical importance.
Projections of a burgeoning population coupled with global environmental change offer an increasingly dire picture of the state of the world's food security in the not-too-distant future. But how can we transform the current food system to become more sustainable, more equitable and more just? We identify kitchens as sites of transformative innovation in the food system where cooks and chefs can leverage traditional food knowledge about local food species to create delicious and nutritious dishes. Achieving a sustainable food system is a grand challenge, one where cooks in particular are stepping forward as innovators to find solutions.
We present a view on global marine fisheries that emphasizes mitigating the conflict between sustainability and the scale of industrial exploitation driven by the demand of continuous economic growth. We then summarize the current state of global fisheries. Finally, we advocate strongly for scaling back industrial fisheries, most of which are non-sustainable. This can be achieved through eliminating the harmful, capacity-enhancing subsidies that prop up industrial fisheries to continue operating despite declining fish stocks. Instead, we propose to support well-managed, locally owned and operated small-scale fisheries, which generally contribute more to local employment and food security. We stress that contrary to deep-seated opinion in the fishing industry and among politicians, reducing overfishing by eliminating overcapacity in fishing fleets will actually lead to greater, not reduced catches. This would address part of the increased global seafood demand over the coming decades, which is driven by population and wealth growth. This seems counterintuitive, but is supported by fisheries science, data and experiences. Thankfully, we are beginning to see that some of these changes are being pursued by a growing number of countries and international institutions.
Seabird bycatch is widely regarded as the greatest threat globally to procellariiform seabirds. Although measures to reduce seabird–fishery interactions have been in existence for many years, uptake in fleets with high risk profiles remains variable. We recorded seabird bycatch and other interactions in the Namibian demersal longline fishery. Interaction rates were estimated for seasonal and spatial strata and scaled up to fishing effort data. Bycatch rates were 0.77 (95% CI 0.24–1.39) and 0.37 (95% CI 0.11–0.72) birds per 1,000 hooks in winter and summer, respectively. Scaling up to 2010, the most recent year for which complete data are available, suggests 20,567 (95% CI 6,328–37,935) birds were killed in this fishery that year. We compared bycatch rates to those from experimental fishing sets using mitigation measures (one or two bird-scaring lines and the replacement of standard concrete weights with 5 kg steel weights). All mitigation measures significantly reduced the bycatch rate. This study confirms the Namibian longline fishery has some of the highest known impacts on seabirds globally, but implementing simple measures could rapidly reduce those impacts. In November 2015 the Ministry of Fisheries and Marine Resources introduced regulations requiring the use of bird-scaring lines, line weighting and night setting in this fishery. A collaborative approach between NGOs, industry and government was important in achieving wide understanding and acceptance of the proposed mitigation measures in the lead up to the introduction of new fishery regulations.
Reproductive aspects of the sea cucumber Athyonidium chilensis were studied over a year in Valdivia, Chile, through gonad index (GI) analysis, macro- and microscopic analysis of the gonads, fecundity and size at first sexual maturity estimations. We also explored the reliability of live size estimators for their use in fisheries. Athyonidium chilensis showed continuous gametogenesis and spawning individuals could be found throughout the year. However, spring was the main reproductive time, where an important GI decrease coincided with enhanced spawning activity evidenced through histology. GIs recovered in summer, and new signs of enhanced spawning activity were observed towards autumn (April 2008). GI peaks were observed in August 2007 and March 2008 for females (22.8 and 24.4% respectively) and September 2007 and March 2008 for males (31.9 and 25.9% respectively). Low mean GIs occurred in May and December 2007 for females (15.2 and 11.6% respectively) and May and October 2007 for males (12.7 and 14.1% respectively). Males reached sexual maturity at a smaller size than females (males: 21.2 g, females: 43.7 g eviscerated weight), and mature females showed a high mean absolute fecundity for a species with lecithotrophic larval development (6.31 × 105 ± 1.97 × 105 SD). For fisheries, we recommend a minimum catch size over 237.89 g drained weight to ensure that caught individuals are sexually mature. This study provides relevant information for the conservation and fishery management of A. chilensis. Continuous gametogenesis and high fecundity make this species particularly suitable for aquaculture in southern Chile.
The status and potential of aquaculture is considered as part of a broader food landscape of wild aquatic and terrestrial food sources. The rationale and resource base required for the development of aquaculture are considered in the context of broader societal development, cultural preferences and human needs. Attention is drawn to the uneven development and current importance of aquaculture globally as well as its considerable heterogeneity of form and function compared with established terrestrial livestock production. The recent drivers of growth in demand and production are examined and the persistent linkages between exploitation of wild stocks, full life cycle culture and the various intermediate forms explored. An emergent trend for sourcing aquaculture feeds from alternatives to marine ingredients is described and the implications for the sector with rapidly growing feed needs discussed. The rise of non-conventional and innovative feed ingredients, often shared with terrestrial livestock, are considered, including aquaculture itself becoming a major source of marine ingredients. The implications for the continued expected growth of aquaculture are set in the context of sustainable intensification, with the challenges that conventional intensification and emergent integration within, and between, value chains explored. The review concludes with a consideration of the implications for dependent livelihoods and projections for various futures based on limited resources but growing demand.
To address growing concern over the effects of fisheries non-target catch on elasmobranchs worldwide, the accurate reporting of elasmobranch catch is essential. This requires data on a combination of measures, including reported landings, retained and discarded non-target catch, and post-discard survival. Identification of the factors influencing discard versus retention is needed to improve catch estimates and to determine wasteful fishing practices. To do this, retention rates of elasmobranch non-target catch in a broad subset of fisheries throughout the world were compared by taxon, fishing country, and gear. A regression tree and random forest analysis indicated that taxon was the most important determinant of retention in this dataset, but all three factors together explained 59% of the variance. Estimates of total elasmobranch removals were calculated by dividing the Food and Agriculture Organization of the United Nations (FAO) global elasmobranch landings by average retention rates, and suggest that total elasmobranch removals may exceed FAO reported landings by as much as 400%. This analysis is the first effort to directly characterize global drivers of discards for elasmobranch non-target catch. The results highlight the importance of accurate quantification of retention and discard rates to improve assessments of the potential impacts of fisheries on these species.
Knowledge of the population dynamics and productivity of exploited species is essential to achieve the sustainable development of fisheries, and to ensure sustainable, long-term use of these resources. The venerid clam Anomalocardia brasiliana is harvested as a fishery resource from the French West Indies to Brazil. Yet, the exploitation of this species is not backed by management or regulations based on scientific knowledge. This can result in reduced (or even depleted) A. brasiliana density and biomass. Here, we examined the population dynamics of A. brasiliana over the course of 1 year at Cidade Beach, a sheltered sandy beach located in south-eastern Brazil. Sampling was done monthly from March 2007 to February 2008. The sampled population was predominantly juvenile. Growth and recruitment were continuous, indicating no major fluctuation in limiting factors, such as temperature, salinity and food. Nevertheless, the abundance and the turnover rate (P/B ratio) of A. brasiliana at Cidade were much smaller than the values observed in other areas of occurrence. The mortality was more intense in young individuals, and the peak of individual production occurred in individuals with a 25 mm shell length, suggesting that individuals smaller than this size should not be exploited.
We describe a new species of Crambionella, C. helmbiru, from central Java, Indonesia. The combination of the mean number of lappets per octant (14), presence of foliaceous appendages amongst frills on oral-arms, absence of tubercles on the velar lappets, proportion of terminal club length to oral-arm length (0.28), and the body colour distinguish this species from three previously described congeners. In addition, the analysis of partial sequences of the cytochrome c oxidase subunit I gene indicate substantial genetic differences from both Crambionella orsini and Crambionella stuhlmanni, supporting the validity of this new species. A combination of morphological and genetic approaches determined that the remarkable differences in exumbrellar colours observed in specimens are simply intra-specific variation. Surprisingly, this species has been commercially harvested for more than 20 years and is well-known to the local people in the region, yet it had remained unknown to science until this point. The commercial fisheries targeting this formerly unknown species are also described in detail.
Members of the Epinephelinae subfamily of serranids (‘grouper’) are heavily
exploited by bottom longline in the Gulf of Gabès located in the south of
Tunisia. In addition to direct mortality, hook and release mortalities
likely occur when fish are caught and released, due to injuries sustained
from hooking as well as those associated with retrieval. During five
experimental trips (29 fishing sets) conducted in August 2011 from the port
of Djerba (south of the Gulf of Gabès), we evaluated the effect of hook
styles (9/0 ‘J’ and 12/0 circle hook) on groupers and non-target species. A
total of 340 specimens representing 10 species were captured. The higher
catch rate was registered for Epinephelus aeneus. The
majority of groupers captured were female mature. The circle hook increased
the capture of the most common grouper E. aeneus and did
not affect the catch of Epinephelus marginatus and
Epinepheleus costae. The effect of the type of hook on
hooking location was inconclusive. Managing of the grouper fishery using
some management actions such as size limits, bag limits, and closed seasons
may prevent more unnecessary losses of grouper species. From this
preliminary study, a definite conclusion for or against the use of circle
hook cannot be drawn. Further research on the role of gear modification and
hook designs in reducing by-catch, hooking-related injury and mortality
should be encouraged.
Cephalopods (Mollusca: Cephalopoda) play an important role as keystone invertebrates in various marine ecosystems, as well as being a valuable fisheries resource. At the World Malacological Congress, held 21–28 July 2013 in Ponta Delgada, Azores, Portugal, a number of cephalopod experts convened to honour the contribution of the late Malcolm R. Clarke, FRS (1930–2013) to cephalopod research. Endorsed by the Cephalopod International Advisory Council (CIAC), the meeting discussed some of the major challenges that cephalopod research will face in the future. These challenges were identified as follows: (1) to find new ways to ascertain the trophic role and food web links of cephalopods using hard tissues, stable isotopes and novel concepts in theoretical ecology; (2) to explore new approaches to the study of cephalopod morphology; (3) to further develop cephalopod aquaculture research; (4) to find new ways to ascertain cephalopod adaptation and response to environmental change; (5) to strengthen cephalopod genetics research; and (6) to develop new approaches for cephalopod fisheries and conservation. The present paper presents brief reviews on these topics, followed by a discussion of the general challenges that cephalopod research is bound to face in the near future. By contributing to initiatives both within CIAC and independent of CIAC, the principle aim of the paper is to stimulate future cephalopod research.
Scattered records of parasitic species infecting commercially important marine fishes in sub-Saharan Africa are known from just a few countries where concerted efforts have been made by local parasitologists (e.g. Senegal, Nigeria, South Africa). Most of these consist of taxonomic records or general surveys of parasite faunas associated with marine hosts, which may or may not have been of commercial value. Little to no multi-disciplinary research is conducted in most parts of sub-Saharan Africa and hence parasitological data are not commonly used to advise fisheries management procedures. This review summarizes current knowledge on all parasitological research associated with commercially important marine fish species in sub-Saharan Africa.
Many marine fisheries in South American Atlantic coasts (SAAC) are threatened by overfishing and under serious risk of collapsing. The SAAC comprises a diversity of environments, possesses a complex oceanography and harbours a vast biodiversity that provide an enormous potential for using parasites as biological tags for fish stock delineation, a prerequisite for the implementation of control and management plans. Here, their use in the SAAC is reviewed. Main evidence is derived from northern Argentine waters, where fish parasite assemblages are dominated by larval helminth species that share a low specificity, long persistence and trophic transmission, parasitizing almost indiscriminately all available fish species. The advantages and constraints of such a combination of characteristics are analysed and recommendations are given for future research. Shifting the focus from fish/parasite populations to communities allows expanding the concept of biological tags from local to regional scales, providing essential information to delineate ecosystem boundaries for host communities. This new concept arose as a powerful tool to help the implementation of ecosystem-based approaches to fisheries management, the new paradigm for fisheries science. Holistic approaches, including parasites as biological tags for stock delineation will render valuable information to help insure fisheries and marine ecosystems against further depletion and collapse.