Article

Disentangling economic, social, and environmental drivers of coral-reef fish trade in Micronesia

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Abstract

Fisheries represent a fundamental resource linking social and ecological systems. Yet, unsustainable fishing regimes prevail across many tropical regions as a result of growing consumer demand and market expansion. Using the extensive reef-fish trade between Chuuk and Guam (Micronesia) as a case study, we examined 12 years of commercial reef-fish export data to capture both inter-annual and intra-annual trends. Reef-fish exports from Chuuk increased steadily between 2003 and 2010 fueled by increasing demand on Guam, but declined sharply from 2010 to 2014 as export costs grew and profit margins were reduced. Intra-annual examinations furthered that low winds and new moon periods were the strongest drivers of daily exports during the initial years of the study, but the governmental disbursement of food-stamp allowances on Guam became the strongest driver in later years when profit margins were lower. Seasonal cycles were also influential, as exports within each year peaked during the Catholic lent season. In sum, the Chuuk-Guam reef-fish trade industry became increasingly dependent on opportunistic demand from Guam, while environmental regimes evolved to become secondary drivers of export volume. The ability to meet foreign demand may suggest a sustainable fishery in Chuuk, however, mounting evidence suggests that consistent supply to international markets masks growing, unsustainable harvesting regimes. Dwindling profits may lead to instability in Guam’s fresh reef-fish trade industry, and also suggested uncertain futures for Chuuk fishers, Guam retailers, and a society dependent on healthy protein. We last compared the sequential expansion of Guam’s reef-fish acquisition footprint across the Indo-Pacific with expansions reported for the Hong Kong live reef food fish trade industry, highlighting the growing impacts of population centers on small-scale coral-reef fisheries as markets globalize.

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... For over a decade,~150 metric tons yr -1 of reef fish from Chuuk, Federated States of Micronesia, have been supplied on average to Guam [23]. Demand on Guam was linked with continued human population growth, limited reef habitat, and the depletion of coastal fisheries [18,24,25]. ...
... Chuuk exports became increasingly driven by demand over this time period, with governmental food allowances in Guam explaining a growing proportion of the variance in daily export records within each month from Chuuk. Cuetos-Bueno and Houk [23] provided further details regarding the study of Chuuk-Guam reef-fish trade, but their findings hinted towards healthy and sustainable stocks in Chuuk given the consistent supply of fresh fish to Guam markets. However, fisheries-independent surveys and anecdotal evidence began reporting ecosystem consequences of Chuuk's expanding fishing footprint [12,[26][27][28]. ...
... Local dynamics of coral-reef fisheries been increasing due to (i) a lack of alternative sources of income for the growing population, (ii) easy access to both local and international markets, (iii) a large governmental distribution of fiberglass motorized boats in the 1980s and 1990s, and iv) limited regulation and enforcement over the last decades. As a result, subsistence fishers in Chuuk lagoon are increasingly turning to commercial fishing to provide a steady income [23,27,32]. Chuuk's reefs are still in good condition when compared across the populated islands of Micronesia [12]. ...
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The consistent supply of fresh fish to commercial markets may mask growing fishing footprints and localized depletions, as fishing expands to deeper/further reefs, smaller fish, and more resilient species. To test this hypothesis, species-based records and fisher interviews were gathered over one year within a large, demand-driven coral-reef fishery in Chuuk, Micronesia. We first assessed catch statistics with respect to high windspeeds and moon phases that are known to constrain both catch and effort. While lower daily catch success was predicted by higher windspeeds and greater lunar illumination, total daily landings fluctuated less than fishing success across environmental gradients. Instead, daily landings were mainly driven by the number of flights from Chuuk to Guam (i.e., international demand). Given that demand masked local drivers of overall catch volume, we further evaluated species-based indicators of fisheries exploitation. Most target species (75%) had either a positively skewed size distribution or proportional contributions that were dependent upon favorable conditions (i.e. season and moon phases). Skewed size distributions indicated truncated growth associated with fishing mortality, and in turn, suggested that size-based management policies may be most effective for these species. In contrast, environmentally-constrained catch success indicated species that may be more susceptible to growing fishing footprints and may respond better to gear/quota/area policies compared to size policies. Species-based responses offered a simplified means to combine species into fisheries management units. Finally, a comparison of commercial and subsistence landings showed higher vulnerability to fishing among species preferentially targeted by commercial fisheries, offering new insights into how commercial harvesting can disproportionately impact resources, despite having lower annual catch volumes.
... Fisheries management and conservation increasingly rely on information linking social and ecological systems (Cuetos-Bueno and Houk, 2018;Kittinger et al., 2015). However, social-ecological systems are complex (Liu et al., 2007) and their management requires cultural context (Berkes et al., 2000). ...
... As a result, fish assemblages in non-MPAs and MPA's lacking positive ecological outcomes were strongly predicted by a fishing access gradient. This finding supports a recent study that concurrent increases in demand for reef fish and commodification of resources can affect even small-island social systems, with eventual repercussions for ecosystems (Cuetos-Bueno and Houk, 2018). ...
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Marine protected areas (MPAs) have emerged as a valuable tool in biodiversity conservation and fisheries management. However, the effective use of MPAs depends upon the successful integration of social and eco- logical information. We investigated relationships between the social system structure of coastal communities alongside biological data describing the status and trends in fish communities around Yap, Micronesia. Traditional marine tenure made Yap an ideal place to investigate the underlying principles of social-ecological systems, as communities own and manage spatially-defined coastal resources. Analysis of social survey data revealed three social regimes, which were linked to corresponding gradients of ecological outcomes. Communities with decentralized decision-making and a preference for communal forms of fishing had the greatest ecological outcomes, while communities lacking any form of leadership were linked to poor ecological outcomes. Interestingly, communities with strong top-down leadership were shown to have variable ecological outcomes, depending on the presence of key groups or individuals. We last investigated whether social per- ception could successfully predict the status of fish assemblages within non-managed reefs. Several biological metrics of fish assemblages within non-managed areas were significantly predicted by a gradient of human access, suggesting social perception could not predict the growing human footprint over the study period. These findings highlight the potentially overlooked role that community-oriented decision-making structures and fishing methods could play in successful conservation efforts, and the limitations of perception data. Policies that promote communal marine resource use offer a novel approach to improve fisheries management and promote social-ecological resilience.
... Fisheries management and conservation increasingly rely on information linking social and ecological systems (Cuetos-Bueno and Houk, 2018;Kittinger et al., 2015). However, social-ecological systems are complex (Liu et al., 2007) and their management requires cultural context (Berkes et al., 2000). ...
... As a result, fish assemblages in non-MPAs and MPA's lacking positive ecological outcomes were strongly predicted by a fishing access gradient. This finding supports a recent study that concurrent increases in demand for reef fish and commodification of resources can affect even small-island social systems, with eventual repercussions for ecosystems (Cuetos-Bueno and Houk, 2018). ...
Article
Marine protected areas (MPAs) have emerged as a valuable tool in biodiversity conservation and fisheries management. However, the effective use of MPAs depends upon the successful integration of social and ecological information. We investigated relationships between the social system structure of coastal communities alongside biological data describing the status and trends in fish communities around Yap, Micronesia. Traditional marine tenure made Yap an ideal place to investigate the underlying principles of social-ecological systems, as communities own and manage spatially-defined coastal resources. Analysis of social survey data revealed three social regimes, which were linked to corresponding gradients of ecological outcomes. Communities with decentralized decision-making and a preference for communal forms of fishing had the greatest ecological outcomes, while communities lacking any form of leadership were linked to poor ecological outcomes. Interestingly, communities with strong top-down leadership were shown to have variable ecological outcomes, depending on the presence of key groups or individuals. We last investigated whether social perception could successfully predict the status of fish assemblages within non-managed reefs. Several biological metrics of fish assemblages within non-managed areas were significantly predicted by a gradient of human access, suggesting social perception could not predict the growing human footprint over the study period. These findings highlight the potentially overlooked role that community-oriented decision-making structures and fishing methods could play in successful conservation efforts, and the limitations of perception data. Policies that promote communal marine resource use offer a novel approach to improve fisheries management and promote social-ecological resilience.
... The Guam snorkel spearfishery now appears largely devoid of higher trophic level species and there are clear signs that a similar trend is occurring in Pohnpei. Guam is now almost wholly reliant on imported reef fish from Chuuk to maintain demand, with herbivores now the main fishing target among Guam spearfishers (Cuetos-Bueno and Houk, 2018). In the Commonwealth of the Northern Mariana Islands, nighttime spearfishing has been reported to be impacting some easily accessible areas, with abundance declines among major spearfishery targets ranging from 40 to 80%, along with CPUE (Bearden et al., 2005). ...
Article
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 fisher¹. 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.
... In the Central and Western Pacific, three grouper species [brown-marbled grouper, Epinephelus fuscoguttatus (Forsskål, 1775); camouflage grouper, E. polyphekadion (Bleeker, 1849); squaretail coralgrouper, Plectropomus areolatus (Rüppell, 1830)] commonly form multi-species FSAs that overlap temporally during at least a portion of their respective spawning seasons and in areas proximate to each other [13,[18][19][24][25]. The timing and location of most FSAs is common knowledge among fishers who have traditionally depended on them for subsistence and, more recently, small-scale commercial interests, including for domestic export [23,[26][27]. In many countries, continuing population growth and an expanding cash economy has intensified FSA fishing [18,[27][28][29], placing aggregations of these and other species under increasing threat [18,21,25]. ...
Article
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Globally, groupers (Epinephelidae) that form fish spawning aggregations (FSAs) are highly vulnerable to overfishing and often require site-specific approaches to management. Over 5-years (2009–2013), we conducted underwater visual censuses (UVC) at a well-known spawning site at Njari Island, Gizo, Western Province, Solomon Islands, that supports aggregations of squaretail coralgrouper (Plectropomus areolatus), camouflage grouper (Epinephelus polyphekadion) and brown-marbled grouper (E. fuscoguttatus). Findings show that while there were species-specific variations in the duration and timing of the spawning season, aggregation densities peaked from March to June, representing the main spawning season for all three species. For P. areolatus, gonad analysis from samples taken from 2008 to 2011 confirmed reproductive activity in support of density trends observed through UVC. Over the 5-year UVC monitoring period, FSA densities declined for P. areolatus and E. polyphekadion. Conversely, following the first year of monitoring, E. fuscoguttatus densities increased. These inter-specific differences may reflect variable responses to fishing as shown elsewhere, or for example, differences in recruitment success. In response to known declines in FSAs of these species, in 2018 the Solomon Islands government placed a nationwide ban on these species’ harvest and sale between October and January. As this study shows, this ban does not encompass the peak aggregation period at Njari and will offer limited protection to other FSAs of these species that are known to vary in reproductive seasonality across the Solomon Islands. A more biologically meaningful and practical management strategy would be to implement a nationwide ban on the harvest and sale of these groupers each month between full and new moons when these FSAs form consistently throughout the country. Since effective management of FSAs typically requires a combined approach, spatial management that protects both spawning sites and reproductive migratory corridors is warranted.
... Similarly, fishery activities can also be affected by external factors, such as natural or environmental disasters (Gephart, Deutsch, Pace, Troell, & Seekelld, 2017), human disasters (e.g. Fernandes et al., 2016), climate change (Allison & Bassett, 2015;Gasalla & Diegues, 2011), labour and production relation changes (Diegues, 1983) and variations in demand and in fishing profits (Cuetos-Bueno & Houk, 2018). In addition, fishery communities and the whole fishery value chain may be affected at different levels in response to human stresses on the fishery systems. ...
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In the Abrolhos Bank (Southwest Atlantic), multidimensional indicators were used in sustainability assessments and eco‐labelling of data‐poor reef fisheries. Potential impacts, risks and stocks vulnerabilities were evaluated based on biological, environmental, social and economic aspects by combining both adapted productivity and susceptibility analysis (PSA) and scale intensity consequence analysis (SICA). Data were obtained from local surveys with stakeholders and experts and from literature. A value chain map revealed final consumers at many locations and middleman presence. Vulnerability to overexploitation ranged from low (Cephalopholis fulva (L.), Lutjanus synagris (L.) and Ocyurus chrysurus (Bloch)) to moderate (Lutjanus jocu (Bloch & Schneider), Epinephelus morio (Val.) and Mycteroperca bonaci Poey). While moderate consequences of the catches were observed to C. fulva, major consequences were identified to the other five stocks. The main threat to coral reef habitats was found to be mining wastes. Poor governance may constrain fisheries sustainability in the region, while the empowerment of fishers in both governance and post‐harvest processes should enhance it.
... Throughout many parts of the world, declining catch and fish biomass has been correlated with distance to population centers (e.g. Albert et al., 2015;Cuetos-Bueno and Houk, 2018;Cinner et al., 2013;Maire et al., 2016). While fish biomass estimates have not been assessed for Gizo, size reductions have been reported (Aswani and Sabetian, 2010) and reductions in local spawning aggregations for groupers (Epinephelidae) are also known (Hughes, 2017). ...
... Localized fisheries depletions are followed by spatial expansions because infrastructure and equipment are committed to keep up with market demand (Birkeland 2004;Swartz et al. 2010;Cinner et al. 2016;Cuetos-Bueno and Houk 2017). For coral reefs, localized depletions are followed by expansions to less accessible (windward, further, and deeper) reefs that historically had less fishing pressure (Teh et al. 2007;Lindfield et al. 2015;Albert et al. 2015). ...
... Localized fisheries depletions are followed by spatial expansions because infrastructure and equipment are committed to keep up with market demand (Birkeland 2004;Swartz et al. 2010;Cinner et al. 2016;Cuetos-Bueno and Houk 2017). For coral reefs, localized depletions are followed by expansions to less accessible (windward, further, and deeper) reefs that historically had less fishing pressure (Teh et al. 2007;Lindfield et al. 2015;Albert et al. 2015). ...
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1. Camouflage grouper, Epinephelus polyphekadion (Bleeker, 1849), and squaretail coralgrouper, Plectropomus areolatus (Rüppell, 1830), are commercially important medium-bodied groupers that aggregate at specific sites and times to spawn and are highly vulnerable to fishing during these events. Populations of both species are in decline globally, such that management specifically targeting these species is warranted. 2. A 12-month fish market survey in Chuuk, Federated States of Micronesia, provided an opportunity to examine age-based reproductive life history of these two groupers and assess whether current management acts to conserve them. Life history characteristics of both E. polyphekadion and P. areolatus include a functionally gonochoristic sexual pattern and rapid growth particularly during early life history. 3. P. areolatus demonstrated early maturity (2.8 years) and a relatively brief lifespan (10 years), while delayed maturity (4.5 years) and higher longevity (25 years) was shown for E. polyphekadion. The spawning seasons for E. polyphekadion and P. areolatus were 2 and 3 months, respectively, which fall entirely within the January–April grouper sales, catch, and export ban period for Chuuk. Marketed catch included 22% E. polyphekadion and 15% P. areolatus juveniles, suggesting that size limits may aid in the conservation of these species. 4. Findings from this and recent grouper life history studies suggest that the current 4-month ban in Chuuk be applied only to grouper species known to reproduce during these months to minimize economic impacts to fishers and market owners, and prevent shifts in fishing pressure to more vulnerable species, such as those with low population turnover times, slow growth, or late maturity. Size limits for catch, sale and export are also warranted as an additional management option.
Thesis
The fishery is a complex and dynamic socio-ecological system involving several actors and knowledge areas. Along the Brazilian coast the small-scale fisheries are very common and provide important ecosystem services. This fishery modality are usually data-poor in terms of catch and abundance data, landing records, quantification of vessels and fishing gear used. This data-limited condition frequently hampers fishery assessments and effective managements. That is the case in the Abrolhos Bank, East Brazil, a wide portion of the shallow continental shelf that encompass a complex benthic habitat with coral reefs, rhodoliths, buracas, mangroves, seaweed banks and with a great biodiversity. Over this area the small-scale fisheries are a traditional activity, extremely diverse in terms of exploitation capacity, fishing gears, target stocks and operating areas. On the Abrolhos Bank, snappers and groupers are very common resources, besides being predators important for the ecosystem equilibrium. However, these stocks are not evaluated or continuously monitored in the fishing landings and any regional fishery management is currently in place. The overall goal of this thesis was to elucidate questions on three snappers (Lutjanus jocu, Lutjanus synagris and Ocyurus chrysurus) and three groupers (Cephalopholis fulva, Epinephelus morio and Mycteroperca bonaci) fishery characteristics, impacts and sustainability in the Abrolhos Bank. The specific objectives were (1) to assess, organize, and analyze these fisheries to find out patterns on stocks occurrence, on fishing fleets and fishing areas, and to propose management units; (2) to examine the abundance trends and the exploitation status of the six stocks through indicators of size, biomass landed, mortality, spawning and yield, and (3) to evaluate the stocks risk to overexploitation and their fishery sustainability considering biological, environmental social and economic aspects. The study was conducted in four coastal communities of the Abrolhos Bank. The data were obtained by interviews with fishers, experts and stakeholders, from fishery landings monitoring databases, by specimens' measures in landings and from literature. Groups of stocks co-occurring in landings and groups of stocks co-occurring in fishing grounds were discovered. Seven similar fishing areas were determined and suggested as spatial management units. Overfishing and decline in the relative abundance were detected to five stocks. The major causes of overfishing were high fishing mortality, low spawning potential ratio, low mega-spawners and high juveniles in landings. The fishery has led some stocks on alert to overexploitation and the results revealed that coral reefs habitat and ecosystem are also threaten by mining waste and dredging. Furthermore, there is a weak environmental governance in the region and insufficient community participation in the construction of management proposals. The results reveal a concerning situation regarding the stocks exploitation status but provide the key points to be worked on together the fishing communities. This thesis emphasizes the need for urgent elaboration of fishery regulation measures in the region and may contribute in the delineating of management proposals in this complex and threatened fishery system.
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One contribution of 16 to a Theme Issue 'Marine regime shifts around the globe: theory, drivers and impacts'. Regime shifts have been observed in marine ecosystems around the world, with climate and fishing suggested as major drivers of such shifts. The global and regional dynamics of the climate system have been studied in this context, and efforts to develop an analogous understanding of fishing activities are developing. Here, we investigate the timing of pelagic marine regime shifts in relation to the emergence of regional and global fishing activities of the Soviet Union. Our investigation of official catch statistics reflects that the Soviet Union was a major fishing actor in all large marine ecosystems where regime shifts have been documented, including in ecosystems where overfishing has been established as a key driver of these changes (in the Baltic and Black Seas and the Scotian Shelf). Globalization of Soviet Union fishing activities pushed exploitation to radically new levels and triggered regional and global governance responses for improved management. Since then, exploitation levels have remained and increased with new actors involved. Based on our exploratory work, we propose that a deeper understanding of the role of global fishing actors is central for improved management of marine ecosystems.
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The individual contribution of natural disturbances, localized stressors, and environmental regimes upon longer-term reef dynamics remains poorly resolved for many locales despite its significance for management. This study examined coral reefs in the Commonwealth of the Northern Mariana Islands across a 12-year period that included elevated Crown-of-Thorns Starfish densities (COTS) and tropical storms that were drivers of spatially-inconsistent disturbance and recovery patterns. At the island scale, disturbance impacts were highest on Saipan with reduced fish sizes, grazing urchins, and water quality, despite having a more favorable geological foundation for coral growth compared with Rota. However, individual drivers of reef dynamics were better quantified through site-level investigations that built upon island generalizations. While COTS densities were the strongest predictors of coral decline as expected, interactive terms that included wave exposure and size of the overall fish assemblages improved models (R2 and AIC values). Both wave exposure and fish size diminished disturbance impacts and had negative associations with COTS. However, contrasting findings emerged when examining net ecological change across the 12-year period. Wave exposure had a ubiquitous, positive influence upon the net change in favorable benthic substrates (i.e. corals and other heavily calcifying substrates, R2 = 0.17 for all reeftypes grouped), yet including interactive terms for herbivore size and grazing urchin densities, as well as stratifying by major reeftypes, substantially improved models (R2 = 0.21 to 0.89, lower AIC scores). Net changes in coral assemblages (i.e., coral ordination scores) were more sensitive to herbivore size or the water quality proxy acting independently (R2 = 0.28 to 0.44). We conclude that COTS densities were the strongest drivers of coral decline, however, net ecological change was most influenced by localized stressors, especially herbivore sizes and grazing urchin densities. Interestingly, fish size, rather than biomass, was consistently a better predictor, supporting allometric, size-and-function relationships of fish assemblages. Management implications are discussed.
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residents can utilize. Fish resources, from traditional subsistence fishing in times past to today's more modern boat-based fisheries, have always been an important component of island economies (Doulman and Kearney, 1991). It is therefore of interest to ex­ amine the current use and potential de­ velopment of such fisheries. An overview of recent trends in the small, but locally important, domestic fisher­ ies in American Samoa is presented in this paper. This includes four fisher­ ies: I) a shoreline subsistence fishery, 2) an artisanal fishery for offshore pe­ lagic fishes, 3) an artisanal fishery for offshore bottomfish, and 4) a recre­ ational tournament fishery. For com­ pleteness and contrast, the much larger distant-water fleet of commercial ves­ sels that deliver tuna to canneries in American Samoa is also briefly described.
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Market demand is often ignored or assumed to lead uniformly to the decline of resources. Yet little is known about how market demand influences natural resources in particular contexts, or the mediating effects of biological or institutional factors. Here, we investigate this problem by examining the Pacific red snapper (Lutjanus peru) fishery around La Paz, Mexico, where medium or "plate-sized" fish are sold to restaurants at a premium price. If higher demand for plate-sized fish increases the relative abundance of the smallest (recruit size class) and largest (most fecund) fish, this may be a market mechanism to increase stocks and fishermen's revenues. We tested this hypothesis by estimating the effect of prices on the distribution of catch across size classes using daily records of prices and catch. We linked predictions from this economic choice model to a staged-based model of the fishery to estimate the effects on the stock and revenues from harvest. We found that the supply of plate-sized fish increased by 6%, while the supply of large fish decreased by 4% as a result of a 13% price premium for plate-sized fish. This market-driven size selection increased revenues (14%) but decreased total fish biomass (-3%). However, when market-driven size selection was combined with limited institutional constraints, both fish biomass (28%) and fishermen's revenue (22%) increased. These results show that the direction and magnitude of the effects of market demand on biological populations and human behavior can depend on both biological attributes and institutional constraints. Fisheries management may capitalize on these conditional effects by implementing size-based regulations when economic and institutional incentives will enhance compliance, as in the case we describe here, or by creating compliance enhancing conditions for existing regulations.
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Overfishing threatens coral reefs worldwide, yet there is no reliable estimate on the number of reef fishers globally. We address this data gap by quantifying the number of reef fishers on a global scale, using two approaches - the first estimates reef fishers as a proportion of the total number of marine fishers in a country, based on the ratio of reef-related to total marine fish landed values. The second estimates reef fishers as a function of coral reef area, rural coastal population, and fishing pressure. In total, we find that there are 6 million reef fishers in 99 reef countries and territories worldwide, of which at least 25% are reef gleaners. Our estimates are an improvement over most existing fisher population statistics, which tend to omit accounting for gleaners and reef fishers. Our results suggest that slightly over a quarter of the world's small-scale fishers fish on coral reefs, and half of all coral reef fishers are in Southeast Asia. Coral reefs evidently support the socio-economic well-being of numerous coastal communities. By quantifying the number of people who are employed as reef fishers, we provide decision-makers with an important input into planning for sustainable coral reef fisheries at the appropriate scale.
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The present study was conducted to identify the existing marketing system and availability of fish species in different markets of Noakhali district of Bangladesh. It was found that the fish distribution chain from producers to consumers was passed through a number of intermediaries: local fish retailers, agents, wholesalers and retailers. Five types of marketing channels were found in this study. The average income of retailer in seven markets was estimated as BDT 591.89/day/retailer whereas the average profit of retailer in seven markets was BDT 450.69/day/retailer. It was found that 19.29% of fish supplied in the markets were carps, 13.29% catfish, 10.43% small fish, 26% marine fish, 22% hilsa, 3.14% prawn and 5.86% others. The number of species landed in the seven different markets was ranged from 43 to 71. The price of fish depends on market structure, species quality, size, weight and season. The price of Catla were found to be varied from 186.67±5.16 to 196.67±5.16 BDT/kg; Rohu160±8.94 to 170±8.94 BDT/kg; Silver carp 113.33±5.16 to 120±8.94 BDT/kg; Hilsa 360±17.89 to 396.67±13.66 BDT/kg; Thai pangus 83.33±5.16 to 90±8.94 BDT/kg and Tilapia 133.33±5.16 to 140±8.94 BDT/kg. It was found that 80% of the fish retailers have improved their livelihood status through fish trading. It is therefore necessary to provide institutional and organizational support, government support and extension services on fish preservation, handling, icing and curing for the development of fish marketing and fish quality.
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Coral reefs are continuing to deteriorate around the world, despite millions of dollars' worth of government effort per year, the commitment of more than 450 nongovernmental organizations, and a long list of successful accomplishments. Researchers and managers must become more aware of positive feedback, including the self-reinforcing ecological, technological, economic, cultural and conceptual processes that accelerate the degradation of coral reefs. Much of the research on coral reef damage has focused on its proximal causes (e.g., global warming, increased atmospheric carbon dioxide, overfishing, pollution, sedimentation, and disease) rather than its ultimate causes, the increasing human population and associated economic demands. To stop the deterioration of coral reef ecosystems, management must be proactive, terminating the self-reinforcing processes of coral reef degradation rather than perpetually restoring reefs or resource stocks. This can be accomplished only by clarifying the entire economic picture to instill more responsible behavior in the public.
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The customary tenure of reef areas in many parts of the South Pacific offers an obvious context within which fishery resources might be managed cooperatively between customary-rights owners and fisheries personnel in government, yet the local foundations for such co-management have received little critical attention. Seven customary fishing rights areas (CFRAs) in Fiji were the focus of the present study, the objective being to compare management of CFRAs subject to differing levels of fishing access and ascertain those factors most influential to local management practices. The intensity of access (‘access pressure’) was measured as the number of licences issued per CFRA and per unit area, while management was assessed as an index, based on evidence of five aspects of management (management structure, marshalling of information for management, approach to goodwill payments, management measures and patrolling and enforcement) derived from questionnaires. Management varied amongst the CFRAs, one of the seven being essentially unmanaged because of a breakdown in succession between chiefs. There was little evidence for management responding uniformly to access pressure; rather, two CFRAs evinced a certain management aptitude regardless of this pressure, and two other CFRAs evinced relatively little management although pressure was high. A simple survey technique can indicate useful contrasts amongst CFRAs in functional local management, and thus be useful for guiding decisions about where to make investments in local management or co-management.
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The simplistic portrayal of road development as a classic environment versus development debate may be because the indirect pathways connecting road building with environmental change are poorly understood. Recent road development in previously remote regions of Nicaragua provides an opportunity to investigate these pathways. This paper examines the effects of increased market access on household resource use on the Atlantic coast of Nicaragua. Specifically, it looks at shifting market flow and price changes for natural resources and corresponding fishing and farming decisions in communities with varying degrees of market access before and after road completion. Fisheries markets were more responsive to market access increases than agricultural markets. With increased access, fishers increasingly sold to non-local buyers, overall export of fisheries' products increased and markets for new products emerged. Prices of fisheries goods were higher with proximity to markets and availability of non-local export outlets, and prices for some were more stable after the road was completed. There were no observed changes in household fishing and farming investments during the year-long study, and therefore the environmental implications of increased market access remain uncertain. Longer-term studies and additional biological monitoring are needed to determine the full environmental consequences of market access.
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Comparable information on the status of natural resources across large geographic and human impact scales provides invaluable context to ecosystem-based management and insights into processes driving differences among areas. Data on fish assemblages at 39 US flag coral reef-areas distributed across the Pacific are presented. Total reef fish biomass varied by more than an order of magnitude: lowest at densely-populated islands and highest on reefs distant from human populations. Remote reefs (<50 people within 100 km) averaged ∼4 times the biomass of "all fishes" and 15 times the biomass of piscivores compared to reefs near populated areas. Greatest within-archipelagic differences were found in Hawaiian and Mariana Archipelagos, where differences were consistent with, but likely not exclusively driven by, higher fishing pressure around populated areas. Results highlight the importance of the extremely remote reefs now contained within the system of Pacific Marine National Monuments as ecological reference areas.
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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(2)) and a moderate human population (34,000 people). However, the estimated harvest volume of 476 mt year(-1) was 8-9 times higher than other jurisdictions. Even on Yap where the reef-fish demand index was lowest (67.7 people km(-2) 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.
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In an effort to deliver better outcomes for people and the ecosystems they depend on, many governments and civil society groups are engaging natural resource users in collaborative management arrangements (frequently called comanagement). However, there are few empirical studies demonstrating the social and institutional conditions conducive to successful comanagement outcomes, especially in small-scale fisheries. Here, we evaluate 42 comanagement arrangements across five countries and show that: (i) comanagement is largely successful at meeting social and ecological goals; (ii) comanagement tends to benefit wealthier resource users; (iii) resource overexploitation is most strongly influenced by market access and users' dependence on resources; and (iv) institutional characteristics strongly influence livelihood and compliance outcomes, yet have little effect on ecological conditions.
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Sustainably managing ecosystems is challenging, especially for complex systems such as coral reefs. This study develops critical reference points for sustainable management by using a large empirical dataset on the coral reefs of the western Indian Ocean to investigate associations between levels of target fish biomass (as an indicator of fishing intensity) and eight metrics of ecosystem state. These eight ecological metrics each exhibited specific thresholds along a continuum of fishable biomass ranging from heavily fished sites to old fisheries closures. Three thresholds lay above and five below a hypothesized window of fishable biomass expected to produce a maximum multispecies sustainable yield (B(MMSY)). Evaluating three management systems in nine countries, we found that unregulated fisheries often operate below the B(MMSY), whereas fisheries closures and, less frequently, gear-restricted fisheries were within or above this window. These findings provide tangible management targets for multispecies coral reef fisheries and highlight key tradeoffs required to achieve different fisheries and conservation goals.
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Using estimates of the primary production required (PPR) to support fisheries catches (a measure of the footprint of fishing), we analyzed the geographical expansion of the global marine fisheries from 1950 to 2005. We used multiple threshold levels of PPR as percentage of local primary production to define 'fisheries exploitation' and applied them to the global dataset of spatially-explicit marine fisheries catches. This approach enabled us to assign exploitation status across a 0.5° latitude/longitude ocean grid system and trace the change in their status over the 56-year time period. This result highlights the global scale expansion in marine fisheries, from the coastal waters off North Atlantic and West Pacific to the waters in the Southern Hemisphere and into the high seas. The southward expansion of fisheries occurred at a rate of almost one degree latitude per year, with the greatest period of expansion occurring in the 1980s and early 1990s. By the mid 1990s, a third of the world's ocean, and two-thirds of continental shelves, were exploited at a level where PPR of fisheries exceed 10% of PP, leaving only unproductive waters of high seas, and relatively inaccessible waters in the Arctic and Antarctic as the last remaining 'frontiers.' The growth in marine fisheries catches for more than half a century was only made possible through exploitation of new fishing grounds. Their rapidly diminishing number indicates a global limit to growth and highlights the urgent need for a transition to sustainable fishing through reduction of PPR.
Chapter
The local diversity and global richness of coral reef fishes, along with the diversity manifested in their morphology, behaviour and ecology, provides fascinating and diverse opportunities for study. Reflecting the very latest research in a broad and ever-growing field, this comprehensive guide is a must-read for anyone interested in the ecology of fishes on coral reefs. Featuring contributions from leaders in the field, the 36 chapters cover the full spectrum of current research. They are presented in five parts, considering coral reef fishes in the context of ecology; patterns and processes; human intervention and impacts; conservation; and past and current debates. Beautifully illustrated in full-colour, this book is designed to summarise and help build upon current knowledge and to facilitate further research. It is an ideal resource for those new to the field as well as for experienced researchers.
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The depletion of natural resources has become a major issue in many parts of the world, with the most accessible resources being most at risk. In the terrestrial realm, resource depletion has classically been related to accessibility through road networks. By contrast, in the marine realm, the impact on living resources is often framed into the Malthusian theory of human density around ecosystems. Here, we develop a new framework to estimate the accessibility of global coral reefs using potential travel time from the nearest human settlement or market. We show that 58% of coral reefs are located less than 30min from the nearest human settlement. We use a case study from New Caledonia to demonstrate that travel time from the market is a strong predictor of fish biomass on coral reefs. We also highlight a relative deficit of protection on coral reef areas near people, with disproportional protection on reefs far from people. This suggests that conservation efforts are targeting low-conflict reefs or places that may already be receiving de facto protection due to their isolation. Our global assessment of accessibility in the marine realm is a critical step to better understand the interplay between humans and resources.
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Fourteen surveys were conducted at Farallon De Medinilla (a U.S. Department of Defense bombing range in the Mariana Archipelago) between 1997 and 2012; annual surveys were conducted from 1999 through 2012. There was no evidence that the condition of the biological resources assessed had changed, or been adversely impacted to a significant degree by the training activities being conducted there. Restricted access has resulted in a de-facto preserve effect and outweighs minor negative impacts from training. The health, abundance and biomass of fishes, corals and other marine resources are comparable to or superior to those in similar habitats at other locations within the Mariana Archipelago. Our research suggests that the greatest threat to FDM's marine resources is from fishermen, not military training activities.
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Nearshore fisheries in the tropical Pacific play an important role, both culturally and as a reliable source of food security, but often remain under-reported in statistics, leading to undervaluation of their importance to communities. We re-estimated nonpelagic catches for Guam and the Commonwealth of the Northern Mariana Islands (CNMI), and summarize previous work for American Samoa for 1950-2002. For all islands combined, catches declined by 77%, contrasting with increasing trends indicated by reported data. For individual island entities, re-estimation suggested declines of 86%, 54%, and 79% for Guam, CNMI, and American Samoa, respectively. Except for Guam, reported data primarily represented commercial catches, and hence under-represented contributions by subsistence and recreational fisheries. Guam's consistent use of creel surveys for data collection resulted in the most reliable reported catches for any of the islands considered. Our re-estimation makes the scale of under-reporting of total catches evident, and provides valuable baselines of likely historic patterns in fisheries catches.
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Marine resource exploitation can deplete stocks faster than regulatory agencies can respond. Institutions with broad authority and a global perspective are needed to create a system with incentives for conservation.
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Fishers often behave in ways that were neither intended, nor anticipated, by managers or policy makers. This is in part because the factors that motivate and constrain behavior – people's preferences and their social characteristics – are overlooked. We used a case study of coral reef artisanal fishers in Seychelles to assess likely responses to different management approaches by identifying the benefits fishers associate with their coral reef environment, the extent to which they prioritize these benefits, and examining how these priorities relate to their social characteristics. We found that fishers identified a diversity of benefits associated with the fishery but overall fishery, option, bequest, and existence benefits were assigned the highest priorities. Fishers who prioritized fishery benefits, identified as “income”, were different to the fishers who prioritized option and bequest benefits, identified as “a right of access for all” and “for our children” – differences that were also reflected in their social characteristics. Fishers who prioritized option and bequest benefits identified avenues to resolve conflicts and were more likely to take action when a norm was broken – characteristics thought to enable cooperation. There was a clear relationship between fishers’ earnings and the extent to which they prioritized both fishery benefits and option benefits. Specifically, fishers with higher earnings tended to prioritize option whereas fishers with lower earnings tended to prioritize fishery benefits. These findings have important implications for fisheries management decision-making. For example, decentralized approaches, such as fisheries co-management, are only likely to succeed for the group of fishers who demonstrated a high likelihood of cooperation. Due to the relationship between earnings and fishers’ priorities, management that influences fishers’ earnings (e.g. through a tax), must consider the likely influence on fishers’ priorities if it is to avoid unexpected or perverse outcomes.
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While there might be differences in details, any definition of ‘sustainability’ must include an element that remains similar over time. For example, this applies to the catches of coral reef fisheries, which cannot be sustainable if exhibiting a strong ascending or descending trend. Thus, despite claims of the efficacy of ‘data-less’ management, at least time series of the catch of coral reef fisheries must be known for valid inferences on their status to be drawn. By contrasting the official and the ‘reconstructed’ coral reef catches of four small island states (Fiji and Tonga in the Pacific, and Jamaica and St Kitts & Nevis in the Caribbean), we show, however, that official catch data, as made available to and by the Food and Agriculture Organization of the United Nations (FAO) not only strongly underestimate catches (from 4 to 17 times for 1950–2010), but also suggest increasing catch trends in 3 of 4 cases, that is, the very opposite of the trend resulting from the bottom-up catch reconstructions. Some implications of these findings, which we think have general currency, are presented.
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Coral reefs support the livelihoods of millions of people, overwhelmingly in developing countries. As reefs become increasingly overfished, scientists and managers frequently suggest that dependence on reef fisheries needs to be reduced. Yet, attempts to do so often fail spectacularly and even result in perverse outcomes because the nature of coral reef livelihoods is often poorly understood. Here, I discuss two emerging threads of social science research that are helping to better shape our understanding about coral reef livelihoods. First is a growing appreciation of the non-material benefits that coral reef fisheries provide to people. Coral reefs contribute to people's identity, lifestyle, and social norms, which create a strong attachment to fishing that can keep people in a fishery. Second, a growing body of research is exploring the role of livelihood diversity in collectively organizing to solve overfishing, complying with fisheries and protected area management, fishing intensity, and willingness to exit the fishery. Importantly, current theory and empirical research does not always support the notion that diversification of livelihoods will lead to reduced fishing effort or lower environmental impacts on coral reefs.
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Global fisheries declines have alerted ecologists that long-term ecosystem assessments require diverse information sources. Non-traditional sources of information on past marine ecosystems have included photographs, newspapers, artwork, and living memory. To date, this information has been taken primarily from historical harvest records, but a secondary and largely untapped wealth of data exists on consumption. Archaeologists have long analyzed preserved midden deposits to understand resource use and its ecological impacts. Restaurant menus may provide a recent analog to middens, given that they document seafood consumption over time and potentially the availability and value of different species in the past. Menus have been used to evaluate historical changes in seafood popularity, but published studies using menus to track wild population abundance are limited. Hawaii is perhaps an ideal location to use menus to analyze historical changes in the marine environment because its remote location meant most locally consumed seafood was locally sourced.
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Parrotfish play two important roles in coral reef social–ecological systems; first as important sources of food for reef dependent people, and second by underpinning the ecological function of herbivory (i.e., grazing of algae) on coral reefs. Overfishing of herbivores can be detrimental to coral reef ecosystems because their removal may allow algae to outcompete corals. However, little is known about the drivers behind the exploitation of parrotfish. We describe the trade of parrotfish in Zanzibar with the aim to visualize the linkages between ecological function, market price, and socioeconomic drivers behind their exploitation. Three interesting findings emerge. First, parrotfish are an important part of the fish trade in Zanzibar and are traded at all market scales (from local consumers to international tourists). Second, size is an important determinant of price, with larger fish generating much higher values. Third, size determines which market parrotfish are sold to. Overall the study shows that all sizes of parrotfish are exposed to exploitation, leaving no size-refuge for escaping harvest. In light of an increasing global demand and high market prices, we thus propose that traditional fisheries management be complemented with assessments of both ecological understanding and socioeconomic dynamics to take into account of global market drivers behind parrotfish exploitation at local scales.
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During 139 visits between March 2009 and May 2011, it was found that the availability of reef fishes at a local fish market in the Philippines was highly affected by the lunar cycle. The number of vendors selling reef fishes was significantly lower (13·4%) during third lunar quarters (full moon periods) than during the first, second and fourth lunar quarters (40·2, 25·0 and 30·0%, respectively). It is recommended that the influence of the lunar cycle on fish availability is considered when designing sampling strategies for catch surveys.
Article
Reef fish are critical in maintaining the ecological function of coral reefs and providing food security for coastal communities in developing countries. Reef fishery stocks are under increasing threat from factors such as climate-related habitat degradation, land use practices, and resource extraction related to human population growth, direct consumption and increasing connectivity between the in situ fishery and fish markets. This study investigates how reef fish stocks are related to environmental, localised resource use and market proximity indicators across 51 sites in the Solomon Islands. Hard coral cover is the best indicator of total target fishery biomass, with cover of less than around 31% associated with significantly less biomass than sites with higher coral cover. Direct resource use indicators such as fish consumption and fish sale pressure were poor predictors of target fish biomass. Distance of the fishery resource from community, provincial sub-station, provincial capital and national capital are all significantly and positively correlated with biomass for four key fishery families: Acanthuridae (surgeonfish), Scaridae (parrotfish), Lethrinidae (emperor), Lutjanidae (snapper). Multiple spatial scale relationships are evident between market proximity indicators and Lutjanidae and Scaridae families. Thus, while pooled target fishery biomass is constrained by environment, analysis at fishery family resolution reveals the effects of anthropogenic impact through market proximity on constraining fishery biomass distribution in the Solomon Islands. This study highlights the need for reef fishery managers and conservation practitioners to focus attention on proximity of resources to markets to sustain the ecological health of reef dominated ecosystems. (C) 2009 Elsevier Ltd. All rights reserved.
Article
Increasing migration into urbanized centers in the Solomon Islands poses a great threat to adjacent coral reef fisheries because of negative effects on the fisheries and because it further erodes customary management systems. Parrotfish fisheries are of particular importance because the feeding habits of parrotfish (scrape and excavate coral) are thought to be critical to the resilience of coral reefs and to maintaining coral reef health within marine protected areas. We investigated the ecological impact of localized subsistence and artisanal fishing pressure on parrotfish fisheries in Gizo Town, Western Solomon Islands, by analyzing the density and size distribution of parrotfish with an underwater visual census (UVC), recall diary (i.e., interviews with fishers), and creel surveys to independently assess changes in abundance and catch-per-unit-effort (CPUE) over 2 years. We then compared parrotfish data from Gizo Town with equivalent data from sites open to and closed to fishing in Kida and Nusa Hope villages, which have different customary management regimes. Results indicated a gradient of customary management effectiveness. Parrotfish abundance was greater in customary management areas closed to fishing, especially with regard to larger fish sizes, than in areas open to fishing. The decline in parrotfish abundance from 2004 to 2005 in Gizo was roughly the same magnitude as the difference in abundance decline between inside and outside customary management marine reserves. Our results highlight how weak forms of customary management can result in the rapid decline of vulnerable fisheries around urbanized regions, and we present examples in which working customary management systems (Kinda and Nusa Hope) can positively affect the conservation of parrotfish--and reef fisheries in general--in the highly biodiverse Coral Triangle region.
Article
There is considerable speculation about the correlation between investments in telecommunications and economic development. Yet, there has been very little research on whether there is a connection between information and communication technologies (ICTs) and economic growth, and if indeed a connection can be established, how it works. Vast populations in developing countries live in rural areas and are subject to the vagaries of their highly inefficient markets. Mobile phones, by virtue of their role as carriers and conduits of information, ought to lessen the information asymmetries in markets, thereby making rural and undeveloped markets more efficient. This article tests this assumption using a case-study from India, where the fishing community in the southwestern state of Kerala has adopted mobile phones in large numbers.Using mobile phones at sea, fishermen are able to respond quickly to market demand and prevent unnecessary wastage of catch-fish being a highly perishable commodity-a common occurrence before the adoption of phones. At the marketing end, mobile phones help coordinate supply and demand, and merchants and transporters are able to take advantage of the free flow of price information by catering to demand in undersupplied markets. There is also far less wastage of time and resources in all segments of the fishing community. Fishermen spend less time idling on shore and at sea, whereas owners and agents go to the landing centers only when they receive information (via mobile phones) that their boats are about to dock. We find that with the widespread use of mobile phones, markets become more efficient as risk and uncertainty are reduced. There is greater market integration; there are gains in productivity and in the Marshallian surplus (sum of consumer and producer surplus); and price dispersion and price fluctuations are reduced. The potential efficiencies are, however, subject to easy access to capital, especially at the production end of the supply chain, without which the market remains less efficient than it could be. Finally, the quality of life of the fishermen improves as they feel less isolated and less at risk in emergencies. (c) 2007 by The Massachusetts Institute of Technology.
Article
The emerging world crisis created by declining fish stocks poses a challenge to resource users and managers. The problem is particularly acute in poor nations, such as those in East Africa, where fishing is an important subsistence activity but high fishing intensity and use of destructive gear have resulted in declining catches. In this context developing effective management strategies requires an understanding of how fishers may respond to declines in catch. We examined the readiness of 141 Kenyan fishers to stop fishing under hypothetical scenarios of declines in catch and how socioeconomic conditions influenced their decisions. As expected, the proportion of fishers that would exit the fishery increased with magnitude of decline in catch. Fishers were more likely to say they would stop fishing if they were from households that had a higher material style of life and a greater number of occupations. Variables such as capital investment in the fishery and the proportion of catch sold had weak, nonsignificant relationships. Our finding that fishers from poorer households would be less likely to exit a severely declining fishery is consistent with the literature on poverty traps, which suggests the poor are unable to mobilize the necessary resources to overcome either shocks or chronic low-income situations and consequently may remain in poverty. This finding supports the proposition that wealth generation and employment opportunities directed at the poorest fishers may help reduce fishing effort on overexploited fisheries, but successful interventions such as these will require an understanding of the socioeconomic context in which fishers operate.