Small-scale fisheries are hard to assess because of the limited availability of data. Therefore, a method requiring easy-to-obtain catch-data is important for the assessment and management of small-scale fisheries. The objective of this study was to assess the effect of fishing gear selectivity on a length-based metric method proposed by Froese by estimating three indicators using catch-data from Lane Snapper (Lutjanus synagris) collected in Honduras. These indicators are (1) the percentage of mature individuals in the catch, (2) the percentage of fish within the range of estimated optimal lengths to be captured, and (3) the percentage of fish larger than the optimal length. These indicators determine the level of overfishing. The indicators were estimated separately for catch-data corresponding to gill nets, and each indicator was estimated with and without selectivity correction. Selectivity and mesh sizes of the fishing gear had a major impact on the estimation of indicators 1 and 2. As for indicator 3, it consistently showed a high level of exploitation. The three estimated indicators suggested that the Lane Snapper fishery in Honduras is experiencing overfishing. Overall, the method appears to be promising for the assessment of small-scale fisheries, but it should be used cautiously.
Sustainable natural resource management requires collaboration, adaptability and coordination between science, policy and stakeholders. Communication of scientific information through social networks is integral to effective governance. This study employed social network analysis to investigate information flow between stakeholders associated with the blue swimmer crab (Portunus armatus) fishery in the Peel-Harvey Estuary, south-western Australia. Although the fishery received Marine Stewardship Council certification in 2016, a preliminary study conducted between 2017 and 2018 revealed that fishers were concerned about its status and management. Consequently, 85 face-to-face interviews were conducted with commercial and recreational fishers, academics, government bodies, representatives of fishing organizations, non-governmental organizations, and tourism operators to understand the flow of information and the influence on perceptions of sustainability. The results showed that: (i) few individuals were key for sharing information within and between different organizations forming the fishery network and only two of the six groups (government bodies and the commercial fishing sector) were highly connected and appeared as key for information sharing; (ii) after the public awareness and tourism groups, academic groups were the second-least connected, despite having actively researched the Peel-Harvey Estuary and the P. armatus fishery for over 40 years; (iii) recreational fishers exchanged information mainly with other fishers and the state fisheries department; (iv) modes of communication used with the recreational fishing sector differed greatly between the fisheries department (i.e., mainly via phone/email) and the recreational fishing organization (i.e., strong online presence, social media, and phone/email); (v) issues of inclusiveness and representativeness were highlighted for some of the groups and organizations. This is the first study looking at information-sharing patterns through an Australian fishery network. Through this research we have identified logistical and institutional challenges to communicating information regarding the science, management and environmental issues related to a small-scale crab fishery and made suggestions to enhance information flow in the network.
The use of small cetaceans as bait is a practice that has been reported worldwide, affecting the conservation status of vulnerable species. In Peru specifically, it has been documented since at least the late 1990s. Here we document the various contemporary uses of small cetaceans, including targeted capture for subsequent use as fishing bait. We designed a survey addressing fishery characteristics, bycatch and the use as bait of small cetaceans, and the history of these practice. We surveyed 147 fishers based in the four Peruvian ports of Paita, Salaverry, Pucusana, and Ilo and held in-depth interviews with 12 fishers from Salaverry and Pucusana. Results from our surveys show that the majority of fishers have had small cetacean bycatch while fishing and that bycaught individuals in gillnets are commonly found dead (Salaverry: 100% of fishers, Pucusana: 58%) whereas in longlines small cetaceans are found alive (Paita: 74%, Ilo: 53%). We found that the use of dolphins as bait is still common in both gillnet and longline shark fisheries along the coast of Peru and that it is more frequent in northern ports. Gillnet fishers reported using one to four dolphins as bait per trip (10–15 sets) from bycatch events and discarding the rest if they have excessive bycatch, while longline fishers reported using 10–20 dolphins per fishing trip from either direct take by harpooning or the exchange of carcasses from gillnet vessels. Bycatch and use as bait mainly affects four species, the dusky, bottlenose and common dolphins and the Burmeister’s porpoise. We identified three drivers of the use of dolphins as bait: effectiveness, availability and cost. These factors will have to be addressed in parallel if this practice is to be reduced. We recommend combining legislative and community-led strategies to reduce bait use and thus further the conservation of small cetacean populations in the southeastern Pacific Ocean.
Small-scale fisheries are globally marginalized by management institutions; thus, they have to endure the consequences of ineffective regulations, environmental uncertainty, social traps and market inequity. Small-scale fisheries in Peru, one of the world’s leading fishing countries, are important contributors to national employment, food security and gross domestic product. Yet, relatively little is known about these fisheries and their evolution, except for the fact that the Peruvian small-scale fleet size is rapidly increasing. Here, we reconstructed small-scale fishing effort across time and developed several indicators using it to assess changes in the fleet’s fishing efficiency and economic performance. Segmented regression analysis was used to identify statistically significant breakpoints and changes in their trajectories between 1950 and 2018. Our results suggest that fishing effort has strongly increased, and at much faster rates than the catches, particularly since 2006. The combined effect of these trends results in significant declines in the fleet’s ratio indicators (i.e., catch per unit of effort, revenue per unit of effort, and fisher’s incomes relative to Peru’s minimum wage), suggesting that the growing fishing effort is unsustainable and uneconomic. The behavior of these indicators differs within the fleet, depending on the vessel’s main fishing method. Most small-scale fishers are currently living in relative poverty. Yet, fishers using the least selective fishing gears, or engaged in illegal fishing, had the most stable incomes over the past decade. These findings are discussed in detail by exploring the social, legal and economic drivers fostering fleet growth. Finally, a list of general recommendations aimed at improving fisheries sustainability and fisher’s wellbeing was produced, based on the local context, fisheries literature and common sense.
The smalltail shark, Carcharhinus porosus, was the most abundant elasmobranch species in fisheries off Brazil’s northern coast (BNC) in the 1980s, but its population has been declining since the 1990s. For this reason, a demographic analysis is necessary to determine the extent of this decline and the fishing effect on the BNC’s population. Therefore, we performed a stochastic demographic analysis of the population in the BNC, and considered its global center of abundance. Smalltail shark specimens (n = 937) were collected with gillnets in Maranhão state, eastern BNC, in the 1980s with sizes ranging between 29.6 and 120.0 cm total length. Most of the individuals (90.6%) caught were juveniles (< 6 years-old), and the mortality and exploitation rates showed that the species was overexploited (92.3% above the fishing mortality corresponding to the population equilibrium threshold). The smalltail shark’s biological characteristics, such as slow growth and low fecundity, demonstrate that it is one of the least resilient species among similar sized coastal sharks in the region. All these factors yielded an annual decrease of 28% in the intrinsic population growth rate, resulting in a population decline of more than 90% in only 10 years, and much higher for the current period. This set of features comprising fishing recruitment occurring upon juveniles, overfishing, and intrinsically low resilience make the population unable to sustain fishing pressure and severely hamper biological recruitment, thus causing this drastic population decline. Furthermore, several local extinctions for this species in the northeastern and southeastern regions of Brazil highlight its concerning conservation scenario. Therefore, since similar fisheries characteristics occur throughout its distribution range, C. porosus fits the criteria E of the IUCN Red List for a critically endangered species and urgent conservation measures are needed to prevent its extinction in the near future.
Small-scale fisheries are an important source of food, income and cultural identity to millions of people worldwide. Despite many fisher people observing declining catches, a lack of data remains a barrier to understanding the status of small-scale fisheries and their effective management in many places. Where data exist, complex analyses and stock assessments are often beyond the capacity and budgets of local managers. Working with small-scale fisheries in western Madagascar, we analyze landings data to provide a description of the fishery and evaluate the top twenty most commonly caught species for evidence of overfishing. Using length composition data, we use Froese’s three simple rules: Let them spawn, let them grow and let the mega-spawners live, as well as Cope and Punt’s decision tree to infer if spawning biomass is less than target reference points. We then use length-based parameters to calculate fishing mortality and compare with published estimates of natural mortality to assess overfishing (F > M). Over 17,000 fishing trips were registered over a 2-year period (2010–2012), landing just short of 2 million individual fish. Length data were recorded for a sample of over 120,000 individuals. Fish comprised 95% of landings, with the remainder comprised of other groups including crustaceans (mostly shrimp, crab, and lobster), cephalopods, and holothurians. We provide some of the first evidence that fish species caught in the small-scale fisheries of the Menabe region of Madagascar are experiencing overfishing. The most notable result is that for 13 of the 20 most common species, fishing mortality exceeds natural mortality. Many species had a large proportion of individuals (in some cases 100%) being caught before they reached maturity. Very few species were fished at their optimal size, and there were low numbers of large individuals (mega-spawners) in catches. Overfishing in western Madagascar presents a serious threat to the income, food security and well-being of some of the most vulnerable people in the world. The results of this paper support the call for improved management. However, management approaches should take account of overlapping fisheries and be inclusive to ensure the impacts of management do not undermine the rights of small-scale fishers. Further data are needed to better understand the trends and to improve management but should not hinder pragmatic action.
Fishing strategies, effort and harvests of small-scale fishers are important to understand for effective planning of regulatory measures and development programs. Gender differences in fishing can highlight inequities deserving transformative solutions, but might mask other important factors. We examined fishing modes, fishing frequency, catch-per-unit-effort (CPUE), resource preferences and perceptions of fishery stock among artisanal gastropod (trochus) fishers in Samoa using structured questionnaires and mixed effects models. The fishery has an extremely modest carbon footprint of 18–23 tons of CO2 p.a., as few fishers used motorized boats. Trochus (Rochia nilotica), an introduced gastropod, was the second-most harvested resource, after fish, despite populations only being established in the past decade. Daily catch volume varied according to gender and villages (n = 34), and was also affected by fishing effort, experience, assets (boat), and fishing costs of fishers. Boat users had much higher CPUE than fishers without a boat. Fishers who practised both gleaning and diving caught a greater diversity of marine resources; effects that explained otherwise seeming gender disparities. Trochus tended to be ranked more important (by catch volume) by women than men, and rank importance varied greatly among villages. Local ecological knowledge of fishers informed the historical colonization of trochus around Samoa and current trends in population abundance. Fishing efficiency, catch diversity and perspectives about stocks were similar between fishermen and fisherwomen, when accounting for other explanatory variables. Greater importance of these shellfish to women, and gender similarities in many of the fishing responses, underscore the need to ensure equal representation of women in the decision making in small-scale fisheries.
Spatial conservation prioritization is used worldwide for designing marine protected areas (MPA) that achieve set conservation objectives with minimal impacts to marine users. People involved in small-scale fisheries (SSF) may incur negative and disproportionate impacts from implementing MPAs, yet limited available data often restricts their representation in MPA planning. Using a Philippines case study, we focus here on the systematic design of a MPA network that aims to minimize and distribute costs equitably for SSF whilst achieving representation targets for biodiversity conservation. The objectives of the study are to: (1) document a participatory mapping approach for collecting SSF data for prioritization using the local knowledge of fishers; and (2) examine how the completeness and resolution of SSF data may affect prioritization outputs in terms of biodiversity representation, spatial efficiency, and distribution equity. In the data-poor region, we conducted participatory mapping workshops with fishers in 79 communities to collect data on the spatial distribution patterns of different SSF fisheries and communities, and employed remote sensing techniques to define coastal habitats, which were targeted for inclusion in MPAs. The datasets were integrated within the decision-support tool Marxan with Zones to develop three scenarios. The SSF data incorporated in each scenario varied based on their completeness (considered all fishing methods or only dominant methods) and resolution (fishing methods itemized by community or municipality). All scenarios derived MPA plans that met representation targets with similar area coverage. The outputs, however, varied in terms of distribution equity, measured by the distribution of opportunity costs (loss of fishing grounds) across different fisheries and communities. Scenarios that did not include minority fisheries or variations between communities, led to inequitable costs. These results highlight the need to incorporate detailed data on SSF at appropriate resolutions, and how this can be achieved through participatory approaches.
China is one of the most important marine fishery countries, yet little is known about its small-scale fisheries (SSFs). This paper uses Hainan Province of China as a case study to examine the present situation, predicaments, and future changes of the country's SSFs during a process of transition from extensive to green development. In doing so, we follow the social-ecological system (SES) framework to present Hainan's SSF-related settings, and study its resource systems, governance systems and actors through reviewing national and local policies, surveying and interviewing SSF stakeholders. Marine fisheries in Hainan is SSF-dominated, experienced dramatic increase in terms of yield and jobs since 1978, and became the main source of most fishermen's livelihood. Fish community structure and fishing targets have shifted from a mix of large-bodied demersals and pelagics to smaller-bodied pelagics with high growth rates and fecundity levels. This degradation puts stress on China's central and local governments to enhance the preservation of marine ecosystems. Effort controls failed to reduce fishing power due to subsidies, a series of measures were introduced in 2015 to correct these problems, including obligatory targets with accountability, subsidy reductions, buyback program, and further reductions of fishing vessels and allowable catch implemented in 2017. Hainan has explored different development directions for SSFs. First, providing policies and funds to reduce small fishing boats and construct larger vessels to support offshore and distant-water fisheries. Second, enhancing fishery value by integrating the development of fishery-related primary, secondary, and tertiary industries. Third, developing existing SSFs in a sustainable manner through standardizing SSF vessel types, delineating operating areas, developing fishing port economy, and building beautiful fishing villages. These practices illustrate that China's centralized government can likely command transformational changes in ecological and socio-economic outcomes according to policy objectives. Also, a broadened perspective that considers the ecological, social, and economic dimensions of SSFs as whole is also crucial. Moreover, the integration of fishery policies with other related socioeconomic policies, and the interdepartmental cooperation is needed to achieve policy consistency across local governments.
The artisanal shrimp fishery in Guyana is important for livelihood and food security, involving around 300 vessels owned and crewed exclusively by Guyanese nationals. This fishery uses Chinese seines and operates in major river estuaries. It targets penaeid shrimp, but also retains some finfish and is known to discard a significant but undocumented quantity of smaller finfish bycatch. The lack of knowledge regarding the bycatch is a concern for fishery management and biodiversity conservation. In this study, we quantify for the first time the finfish bycatch discards through onboard observations (July—August 2016) of a single typical vessel operating in the Demerara estuary. Wet weights of the total catch, retained catch, and finfish discards were recorded separately for each of 76 seine hauls, and subsequently presented as catch rates per trip, catch rates per seine haul (kg/haul), and catch rates standardized per hour of seine net soak—time (kg/hr). A sub—sample of finfish discards was taken from every haul to determine taxonomic composition and species—specific length frequencies. Examination of 2,012 discarded finfish distributed among 32 species revealed high taxonomic diversity, none of which were considered vulnerable by the IUCN Red List. Most finfish discards were small (modal size class 5—7 cm fork length) and included juveniles of 15 species of importance to other fisheries in Guyana. On average, a standardized total catch rate of 14.8 kg was taken per hour of seine net soak—time, yielding 3.9 kg retained catch (shrimp and a few selected finfish), 10.3 kg of finfish bycatch discards, and 0.6 kg of miscellaneous invertebrate discards. This demonstrates significant wastage (finfish discards represent about 69% of the total catch weight) and potential for negative impact on biodiversity and other commercial fisheries. The information provided here addresses an important knowledge gap in the artisanal fisheries of Guyana.