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Coral reef fish assemblages are threatened globally, underscoring the need for data‐driven management to reduce threats and restore populations. Comparing fishery management approaches is aided by a detailed understanding of the key factors controlling species' abundances.The aims of this study were to assess the importance of biophysical factors compared with fishing impacts on the biomass of reef fishes on Florida's Coral Reef and to evaluate the potential effects of common management interventions on fish biomass.Fishing impact was estimated using a fishery‐independent modelling approach and the biomass of the snapper–grouper complex as a proxy for the effects of fishing. Using a separate subset of data from underwater fish surveys, estimated fishing impact was then combined with 18 biophysical variables to model the current biomass of all reef fish species, the snapper–grouper complex, grazing species and species collected for aquaria.Models explained between 51 and 64% of the variance in fish biomass for the fish groups. The strongest predictor of biomass in the snapper–grouper complex was fishing impact (accounting for 25.2% of the explained variance), whereas reef complexity was the strongest predictor for all other groups.High‐resolution maps were produced from the statistical models, including maps of current fish biomass and maps of potential biomass under several management scenarios: a no‐take marine reserve, moderate and extensive coral restoration and the addition of artificial benthic structure. Adding structure had the largest single impact on predicted fish biomass (23–72% increase from current estimated levels). However, beneficial synergies emerged when combining habitat‐based management and fishing closures, with some combinations resulting in a reef‐wide averaged 89% increase in biomass relative to current estimated levels.The results suggest that conservation strategies aimed at protecting and increasing structural reef complexity should be an important part of fishery management discussions. [ABSTRACT FROM AUTHOR]

Multiuse marine protected areas (MPAs) that utilize a mosaic of no-take and sustainable use zones are an increasingly common tool for promoting fish population recovery while minimizing socioeconomic conflict. However, significant gaps remain in our understanding of the effects of multiuse MPAs on reef-fish populations, and how protection from fishing may interact with biophysical gradients to drive ecological outcomes. Here, we examine changes in fish assemblages inside and outside of two multiuse MPAs in Raja Ampat, Indonesia, over the first four to five years after their implementation. We use linear models to assess the impact of protection status, anthropogenic pressure, and biophysical gradients on changes in four biological metrics: abundance, biomass, mean size, and size-spectra. In addition, we use multivariate analyses to assess whether fish assemblages in protected and unprotected reefs diverged after MPA establishment. We find that both fish abundance and biomass were driven equally or more by benthic characteristics than protection status and that these environmental impacts were decoupled from the effects of MPAs. Contrary to expectations, increases in abundance were more pronounced in unprotected reefs, where fish assemblages diverged from protected reefs through an increase of herbivorous parrotfishes (Subfamily Scarinae) likely driven by increased algal production on hard-bottom reef areas. However, mean size and size-spectra improved in sustainable use zones compared to unprotected reefs, demonstrating that non-exclusionary management can provide ecological benefits, especially when combined with nearby no-take areas. Increased mean size was also associated with lower human population sizes, suggesting a strong influence of fishing pressure, which is mediated by MPAs. Our findings suggest that multiuse MPAs can quickly achieve some fisheries management objectives and that these effects are likely to increase over longer timescales. However, biophysical context can have significant impacts on reef-fish assemblages that are distinct from the effects of overlying fisheries management. [ABSTRACT FROM AUTHOR]

Fisheries management relies on various catch and effort controls to preserve spawning stock biomass and maximize sustainable yields while limiting fishery impacts on marine ecosystems. These include species-specific minimum or maximum size limits to protect either small non-reproductive subadults, a portion of reproductively mature adults, or large highly fecund individuals. Protecting size classes of mature fish is expected to yield a viable source of larvae for replenishing populations and reduce the risk of recruitment overfishing, yet size-specific recruitment contributions have rarely been assessed empirically. Here, we apply genetic parentage analysis to measure the reproductive success of a size-structured population of a commercially important species of coral grouper (Plectropomus maculatus—Serranidae) in no-take marine reserves (NTMRs) in the Great Barrier Reef Marine Park, Australia. Although the per capita reproductive success of individual fish increases rapidly with body length, the numerous young mature female fish, below the minimum size limit (MSL) (38 cm total length), were responsible for generating disproportionately large contributions (36%) towards larval replenishment of both fished and reserve reefs. Our findings indicate that MSLs are an effective harvest control measure to safeguard a portion of the spawning stock biomass for coral grouper and supplement recruitment subsidies assured from NTMRs. [ABSTRACT FROM AUTHOR]

Catastrophic overfishing of small‐scale coastal fisheries through the Pacific poses a major threat to regional food security and biodiversity. Globally, approaches to fisheries assessment and management that were developed for industrial fisheries, are failing small‐scale data‐poor fisheries. The Pacific Community has called for a complete rethink of fisheries methodologies for the region; a "new song" of change for small‐scale coastal fisheries. This article describes the application in Fiji of a new approach to facilitating coastal fisheries management reform. Spawning Potential Surveys (SPS) is a pragmatic multi‐disciplinary blend of sciences, that combines a new form of length‐based assessment and communication strategies informed by theories of behavior change, nudge and diffusion, that is initiated with programs of citizen science to inform policy development and catalyze broader societal change. Our project successfully coordinated Fiji‐based NGOs to work with the Ministry of Fisheries, communities, provincial government and supply chains, to collect the data needed to assess ~90% of the Fijian reef fish catch, conduct the analyses needed to develop new management policies, and build a broad consensus in society to support the ongoing reform process that has now been initiated by the Ministry. This project demonstrates the feasibility and effectiveness of the SPS methodology for informing and motivating coastal fisheries reform in the Pacific, as well as the necessity of a long term and multi‐disciplinary approach to achieve the societal change needed. [ABSTRACT FROM AUTHOR]

Social networks have been and remain important in Oceania for building and maintaining social-ecological resilience. However, there is little quantitative information on the role of fish and fishing in resource sharing networks and how networks may be impacted by socioeconomic and environmental changes, which is critical information for developing culturally appropriate fisheries management strategies. To better understand this gap, we conducted social network analysis of sharing networks in 18 villages in Fiji across a socioeconomic gradient. Villages formed two clusters based on network characteristics: villages on the main island had less cohesive networks with more cash and purchased good sharing, while villages located on other islands had more cohesive networks with a greater proportion of natural resource sharing. Metrics of network cohesion were positively correlated with mean household fishing frequency and negatively correlated with measures of material wealth. Fishers reported sharing the largest estimated catch from gillnets and night spearfishing. Given concerns about the sustainability of these fishing practices, we suggest methods for regulating these gears while maintaining fish sharing customs. This study shows how social network analysis can be conducted to better understand sharing networks to support natural resource management. [ABSTRACT FROM AUTHOR]

Parrotfish (family Scaridae) consume macroalgae, an essential process for sustaining the ecological health of coral reefs. They have become fisheries targets in several Caribbean locations, a practice that provisions food and income but also puts reefs at risk. Some countries have banned parrotfish harvest, but this would inflict substantial hardship for resource-poor fishers in some places, given the high proportion of parrotfish species in their catches. This research informs development and assessment of options for achieving the greatest level of population rebuilding with the least hardship imposed on fishers. Fishery models can help compare management options in the absence of real-world examples of how to manage parrotfish populations. We built an agent-based population model for the stoplight parrotfish (Sparisoma viride), a key herbivore and protogynous hermaphrodite, to predict ecological and social outcomes of various fishery management options. We parameterized the model to represent a heavily fished fishery, the context for which assessing different management options is most pertinent. We compared several management options selected through discussions with stakeholders and the scientific literature on fisheries management. We found that all options immediately began to increase population biomass. The more restrictive options led to greater increases in steady-state biomass and revenue from catch, representing a long-term win-win. However, all management options also caused an initial decrease in monetary value of the catch before the eventual rebound, hence a temporal trade-off between short- and long-term economic outcomes. Although there is no perfect strategy, managers and stakeholders can use this information to weigh the costs and benefits of different possible management options in different socialecological contexts. [ABSTRACT FROM AUTHOR]

Spatial expansions can provide a false sense of sustainability to fish markets and their consumers who perceive stable landings through time despite localized depletions. This study examined attributes of monthly landings and changes in size structures within a commercial coral-reef fishery that had stable landings for 11 years. Regression models revealed a significant rise in the ratio of landings between calm and windy months, depicting that stable landings were driven by increased fishing effort or success during the calmer months when less exploited reefs became accessible. Within the calmer months, "race-to-fish" dynamics also evolved for some target species, such as parrotfishes, whose landings became increasingly concentrated towards the onset of calm favorable conditions. During this same time, the size structure for 15 out of 19 target species that comprised 60% of annual landings decreased. The cumulative results suggested that (1) spatial management units can be improved by taking environmental gradients that define fishing access into consideration, and (2) thresholds for size-and-age-based policies should be established with respect to life-history parameters that maximize cohort production and protect against declining size structures. Both recommendations resonate with traditional forms of management across the Pacific that were based on reef tenure and knowledge of how species respond to fishing pressure. [ABSTRACT FROM AUTHOR]

Highlights • Alternative methods to estimate fishing mortality rates from length-frequencies are consistent. • Methods to estimate overfished status are less consistent due to different selectivity assumptions. • The fishery at Glover's Reef Marine Reserve, Belize, is experiencing overfishing. • Both spear and hook and line gear contribute to overfishing, but for different species. Abstract Using information on the species composition and length-frequencies of fish caught in the spear and hook and line fisheries of Glover's Reef Marine Reserve, Belize, we evaluated changes between 2004–2010 and 2011–2017 in single-species and ecosystem sustainability indicators. The two gears differed in species caught, and both changed species composition between time periods, with the line fishers targeting smaller species, and the spear fishers responding to a parrotfish ban by catching more snappers and small groupers, as well as grey angels. Both gears caught smaller fish in 2011–2017 compared to 2004–2010, indicating overfishing. Species often caught immature were black grouper, Nassau grouper and mutton snapper with spears, and black snapper with lines. Most fish of other species were mature, but many were smaller than the optimal size for harvest. Fishing mortality rates were higher than natural mortality rates for most species in both gears in both time periods, whether calculated from average length or by length-based spawning potential ratio (LBSPR), implying that most populations were experiencing overfishing. Many species also had a low spawning potential ratio, implying a high probability that they were overfished. In general, many species were subject to unsustainable levels of fishing, and, according to the Froese indicators, some would benefit from size limits to protect immature individuals. These results are supported despite uncertainty in life history parameters for fishes in Belize, and differences between data poor assessment methods. [ABSTRACT FROM AUTHOR]

Abstract: A holistic basis for achieving ecosystem‐based management is needed to counter the continuing degradation of coral reefs. The high variation in recovery rates of fish, corresponding to fisheries yields, and the ecological complexity of coral reefs have challenged efforts to estimate fisheries sustainability. Yet, estimating stable yields can be determined when biomass, recovery, changes in per area yields and ecological change are evaluated together. Long‐term rates of change in yields and fishable biomass‐yield ratios have been the key missing variables for most coral reef assessments. Calibrating a fishery yield model using independently collected fishable biomass and recovery data produced large confidence intervals driven by high variability in biomass recovery rates that precluded accurate or universal yields for coral reefs. To test the model's predictions, I present changes in Kenyan reef fisheries for >20 years. Here, exceeding yields above 6 tonnes km−2 year−1 when fishable biomass was ~20 tonnes/km2 (~20% of unfished biomass) resulted in a >2.4% annual decline. Therefore, rates of decline fit the mean settings well and model predictions may therefore be used as a benchmark in reefs with mean recovery rates (i.e. r = 0.20–0.25). The mean model settings indicate a maximum sustained yield (MSY) of ~6 tonnes km−2 year−1 when fishable biomass was ~50 tonnes/km2. Variable reported recovery rates indicate that high sustainable yields will depend greatly on maintaining these rates, which can be reduced if productivity declines and management of stocks and functional diversity are ineffective. A number of ecological state‐yield trade‐off occurs as abrupt ecological changes prior to biomass levels that produce MSY. [ABSTRACT FROM AUTHOR]

In Pohnpei, Micronesia, a 10-year (2006–2015) follow-up market survey was conducted to provide the basis for a comparative assessment of the status of the commercial inshore fishery, to inform management and to identify the most relevant management options. Within this timeframe, marketed coral reef fish volumes declined by 50 mt ( ca. 20%), the use of unsustainable fishing methods (nighttime spearfishing and small-mesh gillnets) increased from 75.5% to 81.9%, and catch-per-unit-effort decreased from 3.4 ± 0.1 to 3.2 ± 0.4 kg h −1  fisher 1 . Simultaneously, the economic return as price per unit effort was nearly halved for all gear types. Trip volumes increased, however, this was paralleled by a rise in the average number of fishers per trip, particularly for nighttime spearfishing. Effort shifted from inner to outer reef areas and further away from high fisher density communities. At the family level, increases in the percentage of lower tropic level catch were observed, with herbivores and planktivores increasing in frequency in catch more than other trophic level fishes. The only weight increase among top carnivores was for epinephelids, however this was accompanied by a greater contribution by juveniles for the most commonly targeted grouper, Camouflage grouper, Epinephelus polyphekadion . Among fish families, eight epinephelids were absent in catch in 2015 compared to 2006, with additional species observed in speared catch in 2015 that were absent in 2006. To reverse continuing declines and prevent the potential for fisheries collapse, government needs to institute rights-based management, ban the use of nighttime spearfishing and small-mesh gillnets, and improve existing enforcement within marine protected areas and markets. [ABSTRACT FROM AUTHOR]

Abstract: To design effective marine reserves and support fisheries, more information on fishing patterns and impacts for targeted species is needed, as well as better understanding of their key habitats. However, fishing impacts vary geographically and are difficult to disentangle from other factors that influence targeted fish distributions. We developed a set of fishing effort and habitat layers at high resolution and employed machine learning techniques to create regional‐scale seascape models and predictive maps of biomass and body length of targeted reef fishes for the main Hawaiian Islands. Spatial patterns of fishing effort were shown to be highly variable and seascape models indicated a low threshold beyond which targeted fish assemblages were severely impacted. Topographic complexity, exposure, depth, and wave power were identified as key habitat variables that influenced targeted fish distributions and defined productive habitats for reef fisheries. High targeted reef fish biomass and body length were found in areas not easily accessed by humans, while model predictions when fishing effort was set to zero showed these high values to be more widely dispersed among suitable habitats. By comparing current targeted fish distributions with those predicted when fishing effort was removed, areas with high recovery potential on each island were revealed, with average biomass recovery of 517% and mean body length increases of 59% on Oahu, the most heavily fished island. Spatial protection of these areas would aid recovery of nearshore coral reef fisheries. [ABSTRACT FROM AUTHOR]

Sustainable fisheries management is key to restoring and maintaining ecological function and benefits to people, but it requires accurate information about patterns of resource use, particularly fishing pressure. In most coral reef fisheries and other data-poor contexts, obtaining such information is challenging and remains an impediment to effective management. We developed the most comprehensive regional view of shore-based fishing effort and catch published to date, to show detailed fishing patterns from across the main Hawaiian Islands (MHI). We reveal these regional patterns through fisher “creel” surveys conducted by local communities, state agencies, academics, and/or environmental organizations, at 18 sites, comprising >10,000 h of monitoring across a range of habitats and human influences throughout the MHI. All creel surveys included in this study except for one were previously published in some form (peer-reviewed articles or gray literature reports). Here, we synthesize these studies to document spatial patterns in nearshore fisheries catch, effort, catch rates (i.e., catch-per-unit-effort (CPUE)), and catch disposition (i.e., use of fish after catch is landed). This effort provides for a description of general regional patterns based on these location-specific studies. Line fishing was by far the dominant gear type employed. The most efficient gear (i.e., highest CPUE) was spear (0.64 kg h−1), followed closely by net (0.61 kg h−1), with CPUE for line (0.16 kg h−1) substantially lower than the other two methods. Creel surveys also documented illegal fishing activity across the studied locations, although these activities were not consistent across sites. Overall, most of the catch was not sold, but rather retained for home consumption or given away to extended family, which suggests that cultural practices and food security may be stronger drivers of fishing effort than commercial exploitation for coral reef fisheries in Hawai‘i. Increased monitoring of spatial patterns in nearshore fisheries can inform targeted management, and can help communities develop a more informed understanding of the drivers of marine resource harvest and the state of the resources, in order to maintain these fisheries for food security, cultural practices, and ecological value. [ABSTRACT FROM AUTHOR]

Social and ecological systems come together during the act of fishing. However, we often lack a deep understanding of the fishing process, despite its importance for understanding and managing fisheries. A quantitative, mechanistic understanding of the opportunities fishers encounter, the constraints they face, and how they make decisions within the context of opportunities and constraints will enhance the design of fisheries management strategies to meet linked ecological and social objectives and will improve scientific capacity to predict impacts of different strategies. We examined the case of spearfishing in a Caribbean coral reef fishery. We mounted cameras on fishers’ spearguns to observe the fish they encountered, what limited their ability to catch fish, and how they made decisions about which fish to target. We observed spearfishers who dove with and without the assistance of compressed air, and compared the fishing process of each method using content analysis of videos and decision models of fishers’ targeting selections. Compressor divers encountered more fish, took less time to catch each fish, and had a higher rate of successful pursuits. We also analyzed differences among taxa in this multispecies fishery, because some taxa are known to be ecologically or economically more valuable than others. Parrotfish are ecologically indispensable for healthy coral reefs, and they were encountered and captured more frequently than any other taxon. Fishers made decisions about which fish to target based on a fish’s market value, proximity to the fisher, and taxon. The information uncovered on fishers’ opportunities, constraints, and decision making has implications for managing this fishery and others. Moreover, it demonstrates the value of pursuing an improved understanding of the fishing process from the perspective of the fishers. [ABSTRACT FROM AUTHOR]

Introduction: The state of natural resources is greatly influenced by market access. Consequently, resource trader's incentives, decisions, and willingness to comply with management can influence efforts to achieve sustainability. Trader's impacts will depend on their economic niches, which are influenced by cultural norms, skill, social relationships, profitability, and the spatial scale of markets. Consequently, we examined the potential of traders to influence fisheries' sustainability by evaluating their jobs, gender roles, religion, socioeconomic status, association and perceptions of management systems, and future plans. We studied 142 traders in 19 Kenyan coral reef fisheries landing sites distributed among four gear management systems. Outcomes: We found a strong role of gender, geography, and religion in the participation of these fisheries that was primarily driven by fisheries' profitability. The associations suggest that overfished fisheries should retain traders with low education, capital, and savings – often women; whereas sustainable stocks favor the opposite characteristics, and often men. Conclusions: Therefore, managing for increasing yields, profits, and sustainability could exclude women traders unless they successfully access or adopt the more traditional male economic niche. Gender coexistence is most likely to be achieved by managing for intermediate resource levels where net production, catch, and fish body size diversity are high. Further, reducing risk and increasing the capital and mobility of women traders should reduce their chances of exclusion when fisheries are sustainable. [ABSTRACT FROM AUTHOR]

Kenya’s small scale coral reef fisheries are extensively studied yet a practical understanding of the resilience and status of the main target species remains largely elusive to the manager. We combined a range of fishery and fish population descriptors to analyse Kenya’s coral reef fish and fisheries over a 20 year period from the 1980s, to determine the sustainability of current fishing levels and provide recommendations for management. Fishers reported over 13 different artisanal fishing gears of which there are data for only the five widely used gears. Average catch rates declined 4-fold from the mid 1980s (13.7 ± 1.6 kg/fisher/trip) to the 1990s (3.2 ± 0.1 kg/fisher/trip) and then stabilized. Species richness in catches of these historically multi-species fisheries declined dramatically and by 2007 only 2–3 species appeared in the top bracket (65–75% by number) with Siganus sutor (African whitespotted rabbitfish) and Leptoscarus vaigiensis (marbled parrotfish) consistently being in this bracket in beach seine, gill net and basket trap catches, contributing up to a maximum of 45% and 47% of the catch, respectively. Lethrinus borbonicus dominated handline catches (50%). Relatively stable catch rates are reported from the 1990s to the mid 2000s, likely maintained by shifting proportions of species in the catches. Patterns in fish population densities over time show National Parks have helped increase densities of Lethrinidae and Haemulidae and reduced the decline in densities of Scaridae and Acanthuridae, but that National Reserves have had no positive effect. We suggest that the National Parks, which are No Take Zones (NTZs), and the fisheries regulations inside and outside of Reserves are inadequate for maintaining or restoring reef fishery target families under current levels of fishery exploitation. We propose that recruitment overfishing of several species and insufficient areas under full protection, all exacerbated by climate change, are contributing to driving Kenya’s artisanal coral reef fisheries to a tipping point. We recommend species–specific management options, changes in and enforcement of gear regulations and many more effective NTZs are needed urgently if these fisheries are to continue to provide livelihoods and food security on the Kenyan coast. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Coral grouper (genus Plectropomus), or coral trout, are members of the grouper family (Epinephelidae) and are one of the largest and most conspicuous predatory fishes on Indo-Pacific coral reefs. They are highly-prized food fishes that are targeted by subsistence, artisanal, commercial and recreational fisheries throughout their geographic range. Plectropomus have broadly similar diets and habitat requirements to other tropical groupers, but typically have faster growth and higher natural mortality rates. Although these characteristics are expected to increase population turnover and reduce innate vulnerability to environmental and anthropogenic impacts relative to other groupers, many Plectropomus populations are in decline due to the combined effects of overfishing and habitat degradation. In many locations, stock depletion from uncontrolled fishing, particularly at spawning aggregation sites, has resulted in local fishery collapse. Therefore, improved management of wild populations is urgently required to ensure conservation and sustainable fisheries of Plectropomus. Where possible, a combination of no-take marine reserves, market-based management approaches, and allocation or resurrection of property rights systems are recommended to complement conventional fishery management actions that limit catch and effort. Additional investment in aquaculture propagation is also needed to reduce fishing pressure on wild stocks and support management initiatives. This global synthesis of information pertaining to the biology, fisheries and management of Plectropomus will assist in guiding future management actions that are attempting to address a range of stressors including fishing, reef habitat degradation, and the escalating effects of climate change. [ABSTRACT FROM AUTHOR]

Summary Marine no-take reserves, where fishing and other extractive activities are prohibited, have well-established conservation benefits [ 1 ], yet their impacts on fisheries remains contentious [ 2–4 ]. For fishery species, reserves are often implemented alongside more conventional harvest strategies, including catch and size limits [ 2, 5 ]. However, catch and fish abundances observed post-intervention are often attributed to reserves, without explicitly estimating the potential contribution of concurrent management interventions [ 2, 3, 6–9 ]. Here we test a metapopulation model against observed fishery [ 10 ] and population [ 11 ] data for an important coral reef fishery (coral trout; Plectropomus spp.) in Australia’s Great Barrier Reef Marine Park (GBRMP) to evaluate how the combined increase in reserve area [ 12 ] and reduction in fishing effort [ 13, 14 ] in 2004 influenced changes in fish stocks and the commercial fishery. We found that declines in catch, increases in catch rates, and increases in biomass since 2004 were substantially attributable to the integration of direct effort controls with the rezoning, rather than the rezoning alone. The combined management approach was estimated to have been more productive for fish and fisheries than if the rezoning had occurred alone and comparable to what would have been obtained with effort controls alone. Sensitivity analyses indicate that the direct effort controls prevented initial decreases in catch per unit effort that would have otherwise occurred with the rezoning. Our findings demonstrate that by concurrently restructuring the fishery, the conservation benefits of reserves were enhanced and the fishery cost of rezoning the reserve network was socialized, mitigating negative impacts on individual fishers. [ABSTRACT FROM AUTHOR]

Marine reserves are often established in areas that support fisheries. Larval export from reserves is argued to help compensate for the loss of fishable habitat; however, previous modeling studies have focused on long-term equilibrium outcomes. We examined the transient consequences of reserve establishment for fished metapopulations, considering both a well-mixed larval pool and a spatially explicit model based on a coral trout ( Plectropomus spp.) metapopulation. When fishing pressure was reallocated relative to the area protected, yields decreased initially, then recovered, and ultimately exceeded pre-reserve levels. However, recovery time was on the order of several years to decades. If fishing pressure intensified to maintain pre-reserve yields, reserves were sometimes unable to support the increased mortality and the metapopulation collapsed. This was more likely when reserves were small, or located peripherally within the metapopulation. Overall, reserves can achieve positive conservation and fishery benefits, but fisheries management complementary to reserve implementation is essential. [ABSTRACT FROM AUTHOR]

This paper outlines the benefits of using the framework for an ecosystem approach to fisheries management (EAFM) for dealing with the inevitable yet unclear impacts of climate change and ocean acidification on coastal fisheries. With a focus on the Asia-Pacific region, it summarizes the projected biological and socio-economic effects of increased emissions of carbon dioxide (CO 2 ) for coastal fisheries and illustrates how all the important dimensions of climate change and ocean acidification can be integrated into the steps involved in the EAFM planning process. The activities required to harness the full potential of an EAFM as an adaptation to climate change and ocean acidification are also described, including: provision of the necessary expertise to inform all stakeholders about the risks to fish habitats, fish stocks and catches due to climate change; promotion of trans-disciplinary collaboration; facilitating the participation of all key stakeholders; monitoring the wider fisheries system for climate impacts; and enhancing resources and capacity to implement an EAFM. By channeling some of the resources available to the Asia-Pacific region to adapt to climate change into an EAFM, developing countries will not only build resilience to the ecological and fisheries effects of climate change, they will also help address the habitat degradation and overfishing presently reducing the productivity of coastal fisheries. [ABSTRACT FROM AUTHOR]

The failure of fisheries management among multispecies coral reef fisheries is well documented and has dire implications for the 100 million people engaged in these small-scale operations. Weak or missing management institutions, a lack of research capacity, and the complex nature of these ecosystems have heralded a call for ecosystem-based management approaches. However, ecosystem-based management of coral reef fisheries has proved challenging due to the multispecies nature of catches and the diversity of fish functional roles. We used data on fish communities collected from 233 individual sites in 9 western Indian Ocean countries to evaluate changes in the site's functional composition and associated life-history characteristics along a large range of fish biomass. As biomass increased along this range, fish were larger and grew and matured more slowly while the abundance of scraping and predatory species increased. The greatest changes in functional composition occurred below relatively low standing stock biomass (<600 kg/ha); abundances of piscivores, apex predators, and scraping herbivores were low at very light levels of fishing. This suggests potential trade-offs in ecosystem function and estimated yields for different management systems. Current fishing gear and area restrictions are not achieving conservation targets (proposed here as standing stock biomass of 1150 kg/ha) and result in losses of life history and ecological functions. Fish in reefs where destructive gears were restricted typically had very similar biomass and functions to young and low compliance closures. This indicates the potentially important role of fisheries restrictions in providing some gains in biomass and associated ecological functions when fully protected area enforcement potential is limited and likely to fail. Our results indicate that biomass alone can provide broad ecosystem-based fisheries management targets that can be easily applied even where research capacity and information is limited. Of particular value, is our finding that current management tools may be used to reach key ecosystem-based management targets, enabling ecosystem-based management in many socioeconomic contexts. [ABSTRACT FROM AUTHOR]

The responses of small-scale coastal fisheries to pauses in effort and trade are an important test of natural resource management theories with implications for the many challenges of managing common-pool resources. Three Covid-19 curfews provided a natural experiment to evaluate fisheries responses adjacent a marine reserve and in a management system that restricted small-mesh drag nets. Daily catch weights in ten fish landings were compared before and after the curfew period to test the catch-only hypothesis that the curfew would reduce effort and increase catch per unit effort, per area yields, and incomes. Interviews with key informants indicated that fisheries effort and trade were disrupted but less so in the gear-restricted rural district than the more urbanized reserve landing sites. The expected increase in catches and incomes was evident in some sites adjacent the reserve but not the rural gear restricted fisheries. Differences in compliance and effort initiated by the curfew, changes in gear, and various negative environmental conditions are among the explanations for the variable catch responses. Rates of change over longer periods in CPUE were stable among marine reserve adjacent landing sites but declined faster after the curfew in the gear-restricted fisheries. Two landing sites nearest the southern end of the reserve displayed a daily 45 % increase in CPUE, 25–30 % increase in CPUA, and a 45–56 % increase in incomes. Results suggest that recovering stocks will succeed where authorities can achieve compliance, near marine reserves, and fisheries lacking additional environmental stresses. • Fish catch before and after covid curfews was evaluated in gear and reserve management. • Curfew regulation compliance was higher near the reserve than gear managed sites. • Catch rates and incomes were variable but displayed greatest increases adjacent the reserve. • Rates of changes after the curfew mostly followed the longer-term trends in catches. • Curfew accelerated long-term declines in CPUE in gear-restricted but not reserves fisheries. [ABSTRACT FROM AUTHOR]

Collecting spatial information on fisheries catch and effort is essential to understanding the spatial processes of exploited population dynamics and to manage heterogeneously distributed resources and uses. The use of fishers' knowledge through geographical information systems (GISs) is increasingly considered as a promising source of local information on small-scale coastal fisheries. In this paper we describe the first framework for mapping entire small-scale coastal fisheries using fishers' knowledge on catch size and fishing effort. Four mangrove and coral reef fisheries targeting invertebrates or finfish in New Caledonia (southwest Pacific) were mapped following a five-step framework: (i) stratified random sampling of regular fishers; (ii) collection of fishers' knowledge of fishing areas, fishing effort, and catch size through map-based interviews; (iii) data integration into a spatial geodatabase; (iv) statistical extrapolation of fisher data to the fishery scale; and (v) mapping of catch, effort, and catch per unit effort (CPUE) for each fishery using a GIS overlay procedure. We found evidence that fishers' knowledge supplied precise and accurate quantitative and spatial information on catch size, fishing effort and CPUE for entire fisheries. Fisheries maps captured the fine-scale spatial distribution of fishing activities in a variety of ways according to target taxa, gear type, and home ports. Applications include area-based marine conservation planning and fishery monitoring, management, and governance. This integrated framework can be generalized to a large range of data-poor coastal and inland small-scale fisheries. [ABSTRACT FROM PUBLISHER]

Abstract: Individuals with high discount rates are likely not partial to conservation because they are unwilling to sacrifice short term benefits for potentially higher gains in the future. Many reef fisheries worldwide are open access, and fishers under open access systems are theorized to discount the future at an infinite rate. In contrast, fishers in a customary managed fishery can be expected to be more long term oriented, and thus possibly have lower discount rates. The present study tests this hypothesis by eliciting the discount rates of fishers in an open access small-scale reef fishery, and compares these rates to those of fishers in a customary managed reef fishery. Results indicate that fishers in both open access and traditionally managed reef fisheries have high annual discount rates that are on average over 200%. Contrary to expectations, fishers under an open access system are not associated with higher discount rates compared to customary management. It also appears that a larger proportion of open access fishers are more long-term oriented than those in the customary managed fishery, which is encouraging for the future conservation and sustainability of open access fisheries resources. [Copyright &y& Elsevier]

Abstract: An economic survey of the commercial operators currently active in the Queensland Coral Reef Fin-Fish Fishery has been carried out, as part of a research project aimed at evaluating alternative management options for this fishery. This paper presents the background analysis used as a basis to develop the sampling design for this survey. The background analysis focuses on activity patterns of the fleet based on effort and catch information, as well as patterns of quota ownership. Based on this information, a fishing business profile describing the micro-economic structure of fishing operations is developed. This profile, in conjunction with the qualitative information gained in undertaking the economic surveys, allows preliminary understanding of the key drivers of profitability in the CRFFF, and possible impacts of external factors on fishing operations. [Copyright &y& Elsevier]

Abstract: There is a paucity of information on subsistence reef fisheries of indigenous communities in Torres Strait, Australia, and its role within their hybrid economy. Bus route surveys and semi-structured interviews were conducted in 2005 and 2006 on three islands in Torres Strait to understand whether subsistence fishing remains important for the livelihoods of Torres Strait communities and whether patterns of fishing effort are driven by changes in their socio-economic structure. Strong interactions among private (commercial fishing and other wage-employment), public (social security payments from the State) and subsistence sectors were observed. When social security payments were spent, Islanders were more reliant on subsistence fishing. Also, higher levels of involvement in the private sector corresponded with a shift from shore to boat-based subsistence activities. Socio-economic factors, such as involvement in commercial fishing and social security payments, were identified as the main driving factors of subsistence fishing activities. Findings of the present study stress the importance of considering socio-economic factors explicitly in future fisheries assessments and management decisions concerning the sustainability of resources in Torres Strait. [Copyright &y& Elsevier]

Quantifying progress in management of marine protected areas (MPAs) is crucial to marine conservation and fisheries management in the Philippines. This study compiles data on the status, occurrence, and management gaps of MPAs through coordination with multiple organizations supporting and guiding MPAs in the Philippines. MPA management effectiveness was measured using a MPA Rating System. Since 2002 the modal MPA rating levels increased from level 1 (initiated) to level 4 (sustained) in 2008/9. This upward trend is attributed to factors that promoted both the establishment and improved management of MPAs. Analysis indicated that: (1) most MPAs struggle with budgetary constraints or lack of sustainable financing and (2) overall the MPAs are being maintained and progressing with notable improvement in management despite a range of difficulties encountered during the implementation process. For MPAs in the Visayan Region for which biophysical data were available, the MPA Rating System was used to assess the effectiveness of local government capacity building on MPA coral reef health. Our results suggest that MPAs with higher ratings are likely to have better reef health conditions. [ABSTRACT FROM PUBLISHER]

Abstract: In many parts of the world, inshore marine resources are being increasingly managed through collaborative arrangements between communities, governments, civil society and other groups. However, co-management of fisheries has had a mixture of successes and failures. Theorists and applied researchers have suggested a series of preconditions or factors thought to improve the chances of successful common-pool resource management. These include common property institutional design principles and their contextual conditions. Using a variety of web-based English keyword searches, published literature on community-based management and co-management of coral reefs was systematically reviewed with the view of determining if and how studies were evaluating these management systems as well as the extent to which critical aspects of common property theory were investigated and tested. Based on a screening of 600 and full evaluation of 157 journal articles, four measures of ecological conditions and five measures of contextual condition improvement were examined or could be evaluated with the data presented in 38 papers, which examined 49 co-management projects. Fewer than half of the 49 studies met the inclusion criteria of the analyses for documenting key design principles or contextual conditions. Additionally, most projects did not systematically report on contextual conditions, common property design principles and measures of success. The analysis demonstrates the large theoretical and empirical gaps in the evaluation of these management systems and begs for a more scientific, critical and multivariate approach. [Copyright &y& Elsevier]

A dearth of scientific data surrounding Micronesia's coral-reef fisheries has limited their formal assessment and continues to hinder local and regional management efforts. We approach this problem by comparing catch-based datasets from market landings across Micronesia to evaluate fishery status in the Commonwealth of the Northern Mariana Islands (CNMI), Guam, Yap, and Pohnpei. Initial examinations found that calm weather and low lunar illumination predicted between 6% (Yap) and 30% (CNMI) of the variances in daily commercial landings. Both environmentally driven catch success and daily catch variability increased in accordance with reef-fish demand indices. Subsequent insight from species composition and size-at-capture data supported these findings, highlighting reduced trophic levels and capture sizes where higher human-population-per-reef-area existed. Among the 12-15 target species and/or species complexes that accounted for 70% of the harvest biomass, capture sizes were consistently smallest for CNMI and Guam, often below the reported mean reproductive sizes. Comparatively, Pohnpei has the greatest potential for reef fisheries, with a large reef area (303 km) and a moderate human population (34,000 people). However, the estimated harvest volume of 476 mt year was 8-9 times higher than other jurisdictions. Even on Yap where the reef-fish demand index was lowest (67.7 people km reef habitat), many target fish were harvested below their mean reproductive sizes, including the iconic green bumphead parrotfish and humphead wrasse, as well as several other herbivores. We discuss our results with respect to the contemporary doctrine surrounding size-spectra, catch composition, and catch frequencies that afford insight into fishery pressure and status. We posit that regional catch-based policies (initially) instituted at the market level, combined with area and gear-based restrictions, represent plausible vectors for improving Micronesian fisheries. [ABSTRACT FROM AUTHOR]

The article discusses findings of a study which evaluated temporal patterns in the abundance and distribution of reef fishes at Glover's Atoll in Belize. In 1998, a no-take marine reserve was enforced at the site. Preserve spatial distribution of fishes with respect to reserve boundaries is a significant predictor of species responses to reserve protection. The examined mechanisms for the observed temporal changes to responses of species towards protection in a managed area with a no-take reserve include explicit habitat changes that may affect different species, life-history characteristics, differing susceptibility of fish species to the fishery and differences between species in the effect of the reserve on fishing mortality.

Length, life history and ecological characteristics of landed fish communities were studied over a 10-year period to test theories of fishing disturbance during a time of increased gear and closure management in heavily utilised fisheries. It was predicted that with greater management restrictions: (1) the earliest and fastest responses in the fishery will be seen in those species with faster turnovers, or relatively lower vulnerabilities to fishing; (2) the fishery would transition to a landed catch with higher mean trophic levels, and greater mean body lengths. In addition, the removal of a non-selective, small-mesh seine nets should benefit the catch of gears that previously had the greatest species selectivity overlap with the seine net. Many predictions were supported, although maximum lengths and lengths at maturity responded more rapidly than anticipated. The response to eliminating the non-selective seine net was a more rapid increase in sizes caught by gears with a larger overlap in size (hook and lines) than species selectivity (gill nets). The simultaneous comparison of management systems over time indicates that open-access fishing grounds can benefit from restrictions imposed in adjacent fishing grounds. The study indicated that multi-species coral reef fisheries management objectives of maximising yields, as well as maintaining the fish community's life-history diversity, require management trade-offs that balance local socio-economic and biodiversity needs. [ABSTRACT FROM AUTHOR]

Abstract: On 1st April 2010, the British Government announced designation of the British Indian Ocean Territory – or Chagos Archipelago – as the world’s largest marine protected area (MPA). This near pristine ocean ecosystem now represents 16% of the worlds fully protected coral reef, 60% of the world’s no-take protected areas and an uncontaminated reference site for ecological studies. In addition these gains for biodiversity conservation, the Chagos/BIOT MPA also offers subsidiary opportunities to act as a fisheries management tool for the western Indian Ocean, considering its size and location. While the benefits of MPAs for coral-reef dwelling species are established, there is uncertainty about their effects on pelagic migratory species. This paper reviews the increasing body of evidence to demonstrate that positive, measurable reserve effects exist for pelagic populations and that migratory species can benefit from no-take marine reserves. [ABSTRACT FROM AUTHOR]

Individual transferable quotas (ITQs) are increasingly seen as a way to make fisheries more profitable and halt over-capitalisation. ITQs allocate to users of a resource a share of a total allowable catch (TAC) which they are free to use, lease, or sell. We outline an approach to modelling the effect of an ITQ system in a multi-species, multi-sector fishery and apply it to the Coral Reef Fin Fish Fishery (CRFFF) in Queensland, Australia. An ITQ model, based on the assumption that operators seek to maximize profits, simulates the use of tradeable quota units by operators in the fishery, taking account of the initial quota allocation to operators, seasonal fish prices and individual operator variable costs, their fishing efficiency and experience, and constraints on vessel movements. Rationalization of the fishery is predicted to occur under an ITQ system for the CRFFF, which will lead to reductions in effort, increases in profits, and changes over time in quota prices. The ecological consequences of transferable quota in the multi-species fishery are seen in the catch and discard levels of the less profitable species, even though a TAC was set. This had flow-on effects on biomass. For example, simulations showed that the TAC for the primary target species, coral trout, was used more fully than that for a less valuable target species, red throat emperor, and that this was achieved through increased discarding of red throat emperor. Catches of both coral trout and red throat emperor that were derived from the model were higher than those recently observed in the fishery. The effort predicted by the model, however, closely approximated the actual effort observed in the fishery following implementation of ITQ management. [Copyright &y& Elsevier]

Abstract: This study investigates whether there has been a decline in fish stocks of a coral reef in Thailand, and if so, whether that decline is due to small-scale fishing. The research methods used included fish sampling by UVC, interviews and questionnaires with key informants and artisanal fishers. The results confirmed that there has been a decline in piscivores and carnivores (though not herbivores), and the main perceived threat came not from artisanal but from commercial fishing. Recommendations are to replace the largely unrestricted fishery with a more regulated regime backed by effective enforcement. [Copyright &y& Elsevier]

Abstract: Six species of line-caught coral reef fish (Plectropomus spp., Lethrinus miniatus, Lethrinus laticaudis, Lutjanus sebae, Lutjanus malabaricus and Lutjanus erythropterus) were tagged by members of the Australian National Sportsfishing Association (ANSA) in Queensland between 1986 and 2003. Of the 14,757 fish tagged, 1607 were recaptured and we analysed these data to describe movement and determine factors likely to impact release survival. All species were classified as residents since over 80% of recaptures for each species occurred within 1km of the release site. Few individuals (range 0.8–5%) were recaptured more than 20km from their release point. L. sebae had a higher recapture rate (19.9%) than the other species studied (range 2.1–11.7%). Venting swimbladder gases, regardless of whether or not fish appeared to be suffering from barotrauma, significantly enhanced (P <0.05) the survival of L. sebae and L. malabaricus but had no significant effect (P >0.05) on L. erythropterus. The condition of fish on release, subjectively assessed by anglers, was only a significant effect on recapture rate for L. sebae where fish in “fair” condition had less than half the recapture rate of those assessed as in “excellent” or “good” condition. The recapture rate of L. sebae and L. laticaudis was significantly (P <0.05) affected by depth with recapture rate declining in depths exceeding 30m. Overall, the results showed that depth of capture, release condition and treatment for barotrauma influenced recapture rate for some species but these effects were not consistent across all species studied. Recommendations were made to the ANSA tagging clubs to record additional information such as injury, hooking location and hook type to enable a more comprehensive future assessment of the factors influencing release survival. [Copyright &y& Elsevier]

Commercial coral reef fisheries in Pohnpei (Micronesia) extract approximately 1,521 kg of reef fish daily (500 MT year-1) from 152 km2 of surrounding reef. More than 153 species were represented during surveys, with 25 species very common or common within combined-gear catch. Acanthurids contributed the greatest to catch volume, with bluespine unicornfish, Naso unicornis, and orangespine unicornfish, Naso lituratus, among the most frequently observed herbivores. Nighttime spearfishing was the dominant fishing method and inner lagoon areas were primarily targeted. A seasonal sales ban (March-April), intended to reduce pressure on reproductively active serranids, significantly increased the capture volume of other families. Catch was significantly greater during periods of low lunar illumination, suggesting higher fishing success or greater effort, or both. The marketed catch was dominated by juveniles and small adults, based on fishes of known size at sexual maturity. Artificially depressed market prices appear to be catalyzing (potential or realized) overfishing by increasing the volume of fish needed to offset rising fuel prices. These results support the need for comprehensive fisheries management that produces sustainable fishing and marketing practices and promotes shared management and enforced responsibilities between communities and the state. To be effective, management should prohibit nighttime spearfishing. [ABSTRACT FROM AUTHOR]

• Reef fish biomass was low (<25 g m−2) at 83 % of sites across Palau. • Highest biomass was found in the fore-reef west habitat and Northern Reefs region. • SPR was 20–40 % for the majority of assessed species. Palau has a rich tradition of fisheries management and stewardship of its waters, and as in many island nations, small-scale coral reef fisheries are a vital part of the local culture, economy, and food security. However, reef fisheries in Palau are data-poor and there is increasing concern that reef fish stocks are declining. To evaluate the current and future status of these resources, information is needed on the abundance, biomass, and size structure of reef fish resource species. To this aim, the Palau International Coral Reef Center (PICRC) conducted a nation-wide study to investigate the status of commercially important reef fish stocks in 2017. Fishery-independent surveys were conducted by diver operated stereo-video (stereo-DOV) at 94 sites across the archipelago. Results showed that fish biomass varied from 0.13 to 293 g m−2. Habitat was the most significant predictor of fish biomass, with the highest biomass found at western fore-reef sites and the lowest at inner reef sites. Region also affected fish biomass, with significantly higher biomass found in the Northern Reefs compared to those around Babeldaob (the largest island in Palau). In channel habitats, marine protected area (MPA) proximity, fishing pressure from Koror (Palau's main population center), and local fishing pressure significantly influenced fish biomass. In western fore-reef habitats, fish biomass was significantly affected by region, with differences observed between the Northern Reefs and Babeldaob, and between the Southern Reefs and Babeldaob. Fishing pressure from Koror had a significant effect on fish biomass in inner reef habitats, with a weak negative relationship observed. Using length frequencies from the stereo-DOV surveys we also estimated spawning potential ratio (SPR) for seven species and found the majority had SPR values between 20 % and 40 %. Overall, the low fish biomass and SPRs suggests that many of Palau's principal fisheries species have been overexploited. This is the first study to evaluate the status of resource reef fish stocks across the main islands of Palau and provides a baseline to assess changes in fish populations over time. [ABSTRACT FROM AUTHOR]