64 research outputs found
Positive Catch and Economic Benefits of Periodic Octopus Fishery Closures: Do Effective, Narrowly Targeted Actions 'Catalyze' Broader Management?
Eight years of octopus fishery records from southwest Madagascar reveal significant positive impacts from 36 periodic closures on: (a) fishery catches and (b) village fishery income, such that (c) economic benefits from increased landings outweigh costs of foregone catch. Closures covered 20% of a village's fished area and lasted 2-7 months.We discuss the implications of our findings for broader co-management arrangements, particularly for catalyzing more comprehensive management
Transparent and feasible uncertainty assessment adds value to applied ecosystem services modeling
We introduce a special issue that aims to simultaneously motivate interest in uncertainty assessment (UA) and reduce the barriers practitioners face in conducting it. The issue, âDemonstrating transparent, feasible, and useful uncertainty assessment in ecosystem services modeling,â responds to findings from a 2016 workshop of academics and practitioners that identified challenges and potential solutions to enhance the practice of uncertainty assessment in the ES community. Participants identified that one important gap was the lack of a compelling set of cases showing that UA can be feasibly conducted at varying levels of sophistication, and that such assessment can usefully inform decision-relevant modeling conclusions. This article orients the reader to the 11 other articles that comprise the special issue, and which span multiple methods and application domains, all with an explicit consideration of uncertainty. We highlight the value of UA demonstrated in the articles, including changing decisions, facilitating transparency, and clarifying the nature of evidence. We conclude by suggesting ways to promote further adoption of uncertainty analysis in ecosystem service assessments. These include: Easing the analytic workflows involved in UA while guarding against rote analyses, applying multiple models to the same problem, and learning about the conduct and value of UA from other disciplines
Managing Local Stressors for Coral Reef Condition and Ecosystem Services Delivery Under Climate Scenarios
Coral reefs provide numerous ecosystem goods and services, but are threatened by multiple environmental and anthropogenic stressors. To identify management scenarios that will reverse or mitigate ecosystem degradation, managers can benefit from tools that can quantify projected changes in ecosystem services due to alternative management options. We used a spatially-explicit biophysical ecosystem model to evaluate socio-ecological trade-offs of land-based vs. marine-based management scenarios, and local-scale vs. global-scale stressors and their cumulative impacts. To increase the relevance of understanding ecological change for the public and decision-makers, we used four ecological production functions to translate the model outputs into the ecosystem services: âState of the Reef,â âTrophic Integrity,â âFisheries Production,â and âFisheries Landings.â For a case study of Maui Nui, Hawaiâi, land-based management attenuated coral cover decline whereas fisheries management promoted higher total fish biomass. Placement of no-take marine protected areas (MPAs) across 30% of coral reef areas led to a reversal of the historical decline in predatory fish biomass, although this outcome depended on the spatial arrangement of MPAs. Coral cover declined less severely under strict sediment mitigation scenarios. However, the benefits of these local management scenarios were largely lost when accounting for climate-related impacts. Climate-related stressors indirectly increased herbivore biomass due to the shift from corals to algae and, hence, greater food availability. The two ecosystem services related to fish biomass increased under climate-related stressors but âTrophic Integrityâ of the reef declined, indicating a less resilient reef. âState of the Reefâ improved most and âTrophic Integrityâ declined least under an optimistic global warming scenario and strict local management. This work provides insight into the relative influence of land-based vs. marine-based management and local vs. global stressors as drivers of changes in ecosystem dynamics while quantifying the tradeoffs between conservation- and extraction-oriented ecosystem services
Cultural bequest values for ecosystem service flows among indigenous fishers: A discrete choice experiment validated with mixed methods
a b s t r a c t a r t i c l e i n f o Perhaps the most understudied ecosystem services are related to socio-cultural values tied to non-material benefits arising from human-ecosystem relationships. Bequest values linked to natural ecosystems can be particularly significant for indigenous communities whose livelihoods and cultures are tied to ecosystems. Here we apply a discrete choice experiment (DCE) to determine indigenous fishers' preferences and willingness-to-pay for bequest gains from management actions in a locally managed marine area in Madagascar, and use our results to estimate an implicit discount rate. We validate our results using a unique rating and ranking game and other mixed methods. We find that bequest is highly valued and important; respondents were willing to pay a substantial portion of their income to protect ecosystems for future generations. Through all of our inquiries, bequest emerged as the highest priority, even when respondents were forced to make trade-offs among other livelihood-supporting ecosystem services. This study is among a relative few to quantify bequest values and apply a DCE to model trade-offs, value ecosystem service flows, and estimate discount rates in a developing country. Our results directly inform coastal management in Madagascar and elsewhere by providing information on the socio-cultural value of bequest in comparison to other ecosystem service benefits
Conservation policies informed by food system feedbacks can avoid unintended consequences
Understanding the feedbacks between food systems and conservation policies can help avoid unintended environmental consequences. Using a survey-based choice experiment and economic modelling, we quantify the potential impact of touristsâ responses to a shift in offshore fish supply after the designation of a large-scale marine protected area in Palau. We find that this conservation policy may increase offshore fish prices and touristsâ consumption of reef fish, thereby further endangering local reef ecosystems. However, if tourists are offered a sustainable offshore choice, their demand for fish could be kept at current levels, and environmental impacts from increased reef fish consumption would be avoided
Combining fish and benthic communities into multiple regimes reveals complex reef dynamics
Abstract Coral reefs worldwide face an uncertain future with many reefs reported to transition from being dominated by corals to macroalgae. However, given the complexity and diversity of the ecosystem, research on how regimes vary spatially and temporally is needed. Reef regimes are most often characterised by their benthic components; however, complex dynamics are associated with losses and gains in both fish and benthic assemblages. To capture this complexity, we synthesised 3,345 surveys from Hawaiâi to define reef regimes in terms of both fish and benthic assemblages. Model-based clustering revealed five distinct regimes that varied ecologically, and were spatially heterogeneous by island, depth and exposure. We identified a regime characteristic of a degraded state with low coral cover and fish biomass, one that had low coral but high fish biomass, as well as three other regimes that varied significantly in their ecology but were previously considered a single coral dominated regime. Analyses of time series data reflected complex system dynamics, with multiple transitions among regimes that were a function of both local and global stressors. Coupling fish and benthic communities into reef regimes to capture complex dynamics holds promise for monitoring reef change and guiding ecosystem-based management of coral reefs
Towards an ecosystem-based approach of Guam\u27s coral reefs: The human dimension
Management of tropical reef ecosystems under pressure from terrestrial and extractive marine activities is not straightforward, especially when the interests of extractive and non-extractive marine resource sectors compete. Before implementing management actions, potential outcomes of alternative management strategies can be evaluated in order to avoid adverse or unintended consequences. In tropical reef ecosystems the continued existence of the cultural and recreational fishing activities and the economically important dive-based tourism and recreation industry rest on sustainably managed marine resources. Through a case study of Guam, an ecosystem model was linked with human behavior models for participation in fishing and diving to evaluate future socio-ecological impacts of different management options. Ecosystem indices for reef status and resilience, and extraction potential were identified to evaluate the performance of alternative management scenarios. These marine ecosystem indices link the natural system to human uses (fishing and dive-based tourism and recreation). Evaluating management scenarios indicate that applying a single management tool, such as input controls or marine preserves, without also managing the watershed, is suboptimal. Combining different management tools has negative near-term costs, particularly for the fishing sector, but these are likely to be outweighed by the long-term benefits obtained from greater species abundance. Adopting watershed management measures in addition to fishery regulations distributes the burden for improving the reef status across multiple sectors that contribute to reef pressures
Fishing site mapping using local knowledge provides accurate and satisfactory results: Case study of Octopus fisheries in Madagascar
Accurate fishing ground maps are necessary for fisheries monitoring. In Velondriake locally managed marine area (LMMA) we observed that the nomenclature of shared fishing sites (FS) is villages dependent. Additionally, the level of illiteracy makes data collection more complicated, leading to data collectors improvising when recording FS. In this case study for Velondriake we opted for a participatory approach giving special consideration to local knowledge in mapping octopus fishing grounds. Other techniques (single or multiple GPS points) have been tried but gave overlapping maps for neighboring FS, and do not reflect reality. Local fishers know the exact extent of their fishing grounds and are able to draw them accurately. We utilized a printed habitat map or Google Earth satellite imagery, and asked fishers to draw in each FS. Using this technique, 325 sites were identified from 13 villages, without any overlaps or duplications, making a valuable contribution to fisheries management efforts. This supports the contention that local knowledge, and the participation of local fishers, is crucial in conservation. This approach strengthens the relationship between scientists, managers and local communities. This technique is cost effective and adaptable to each situation, and is now widely used by Malagasy fishing communities.
Follow that fish: Uncovering the hidden blue economy in coral reef fisheries
<div><p>Despite their importance for human well-being, nearshore fisheries are often data poor, undervalued, and underappreciated in policy and development programs. We assess the value chain for nearshore Hawaiian coral reef fisheries, mapping post-catch distribution and disposition, and quantifying associated monetary, food security, and cultural values. We estimate that the total annual value of the nearshore fishery in HawaiÊ»i is 16.4 million, composed of non-commercial (12.9 million) and commercial (148,500-$445,500 unlicensed) catch. Hawaiiâs nearshore fisheries provide >7 million meals annually, with most (>5 million) from the non-commercial sector. Over a third (36%) of meals were planktivores, 26% piscivores, 21% primary consumers, and 18% secondary consumers. Only 62% of licensed commercial catch is accounted for in purchase reports, leaving 38% of landings unreported in sales. Value chains are complex, with major buyers for the commercial fishery including grocery stores (66%), retailers (19%), wholesalers (14%), and restaurants (<1%), who also trade and sell amongst themselves. The bulk of total nearshore catch (72â74%) follows a short value chain, with non-commercial fishers keeping catch for household consumption or community sharing. A small amount (~37,000kg) of reef fishâthe equivalent of 1.8% of local catchâis imported annually into HawaiÊ»i, 23,000kg of which arrives as passenger luggage on commercial flights from Micronesia. Evidence of exports to the US mainland exists, but is unquantifiable given existing data. Hawaiian nearshore fisheries support fundamental cultural values including subsistence, activity, traditional knowledge, and social cohesion. These small-scale coral reef fisheries provide large-scale benefits to the economy, food security, and cultural practices of HawaiÊ»i, underscoring the need for sustainable management. This research highlights the value of information on the value chain for small-scale production systems, making the hidden economy of these fisheries visible and illuminating a range of conservation interventions applicable to HawaiÊ»i and beyond.</p></div
Description of fish dealer categories according to Hawaiâi DAR.
<p>Description of fish dealer categories according to Hawaiâi DAR.</p
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