Small-scale Fleet Research Articles

Implications of the WTO and EU fuel taxation reforms for a European fishing fleet: effects, side-effects and alternative approaches from an input–output analysis of the Galician (northwest Spain) fleet

The World Trade Organization (WTO) and European Union (EU) have both put forward tax reforms that impact fisheries’ fuel costs, which are similar in the object of taxation but quite different in the externalities addressed, goals, scope, exemptions or tax rates, creating an opportunity to compare the effects and discuss the alternatives. These proposals are the result of long and intense debates in political, social and academic spheres. However, certain aspects remain unclear. First of all, the number of empirical studies is still limited, particularly considering that fisheries governance is subject to heterogeneous management systems and institutional contexts creating room for different potential outputs. Second, coastal states have no fiscal competence beyond 12 miles, which limits the scope of the reforms to small scale fleets (SSF). All in all, the economic consequences for the fleets remain unclear. To this end, we will build on the Galician fishing sector (NW Spain) input–output tables to discuss the direct impacts, effects and side effects of these reforms on a representative European fleet. Flaws identified in both initiatives mean that targeted externalities will not be corrected and, moreover, additional ones, such as distributional effects penalising SSF or fuel spillovers, could be boosted. Alternative policy approaches are discussed.

Using social media image to identify threatened elasmobranch species caught by a small-scale fishery in a data-poor area.

Sharing fishing activity via social media attracts millions of views. The data from these shares includes key information for a fisheries database such as the species present in the catches and in many cases the number of specimens caught. Many countries in the Global South do not have official information about basic data on fishing activity, especially small-scale activity. In many of such countries like Brazil, overfishing poses a significant threat to numerous threatened species, including elasmobranchs, due to the frailty of fisheries management and law enforcement. The lack of a national (Brazil) data collection program makes sharing data on social media a potential source of fisheries related information. Hence, this study aimed to verify the potential of social media data to describe artisanal fishing and identify elasmobranch species caught by a small-scale fleet in a data-poor Equatorial Southwest Atlantic region. The identification of elasmobranch species was made based on 250 videos shared by local fishers publicly on social media (Youtube™). Among these, sharks and rays were observed in 19 (8%) and 42 (17%) videos, respectively. A total of 98 specimens were recorded, of which 80% could be identified to a species level. Most of the records comprised the stingrays Hypanus berthalutzae and Hypanus guttatus, while Ginglymostoma cirratum was the most recorded shark. More than half of the elasmobranch species recorded are listed at some level of threat according to the IUCN Red List. According to the Brazilian legislation, at least 20% of the species identified in these videos are considered Endangered (EN) or Critically Endangered (CR). Therefore, fishing activity shared via social media can be considered effective in identifying threatened elasmobranch species, as well as providing data on species occurrence, number of specimens, or rare sightings. It is suggested that fishing activity shared via social media be used in parallel with traditional methods (e.g. on-board data and landing observations) to obtain fisheries information and data about endangered species in data poor areas.

Factors affecting the relative abundance in an overfished stock: red grouper (Epinephelus morio) in the Southeastern Gulf of Mexico.

The most important fisheries are recording catches below their historical averages despite increased effort. This level of overfishing is worrying and requires the establishment of feasible and precise measures to prevent a continuing decrease in biomass. Determining the factors that lead to changes in the abundance and distribution of overfished resources would allow us to identify the strengths and weaknesses of management schemes; this approach would also make it possible to estimate more accurate parameters for their evaluation. We hypothesize that environmental, temporal, spatial, and operational components contribute to the variation in the relative abundance. Thus, we analyzed the red grouper fishery, the most important demersal fishery in the southeastern Gulf of Mexico (SGM); it is locally known as escama. We employed the catch per unit effort (CPUE) as an index of relative abundance recorded by the semi-industrial fleet (kilogram per effective fishing day) and the small-scale fleet (kilogram per effective fishing hour) during the overexploitation phase (from 1996 to 2019). We fitted several variables of the components using generalized additive models (GAM) and used multi-model inference to determine the best GAM for each fleet. For both fleets, the operational and temporal components (fishing gear and year) have had a greater impact on the distribution and abundance of red grouper in the SGM than the spatial and environmental components (the place of origin and sea surface temperature). These findings encourage the exploration of métier schemes for more efficient fishery management. In addition, we have identified several strategies that would support the recovery of the resource, such as restricting fishing in the quadrants located to the northeast or regulating scuba diving. We recommend that in the future, researchers use the indices we have generated in the present study to evaluate the red grouper fishery.

An overview of the impacts of fishing on seabirds, including identifying future research directions

Abstract Knowledge of fisheries impacts, past and present, is essential for understanding the ecology and conservation of seabirds, but in a rapidly changing world, knowledge and research directions require updating. In this Introduction and in the articles in this Themed Set “Impacts of fishing on seabirds”, we update our understanding of how fishing impacts seabird communities and identify areas for future research. Despite awareness of the problems and mitigation efforts for >20 years, fisheries still negatively impact seabirds via the effects of bycatch, competition, and discards. Bycatch continues to kill hundreds of thousands of seabirds annually, with negative population-level consequences. Fisheries for forage fish (e.g. anchovy, sandeel, and krill) negatively impact seabirds by competing for the same stocks. Historically, discards supplemented seabird diets, benefitting some species but also increasing bycatch rates and altering seabird community composition. However, declining discard production has led to potentially deleterious diet switches, but reduced bycatch rates. To improve research into these problems, we make the following recommendations: (1) improve data collection on seabird–vessel interaction and bycatch rates, on fishing effort and vessel movements (especially small-scale fleets), and on mitigation compliance, (2) counter the current bias towards temperate and high-latitude ecosystems, larger-bodied species and particular life stages or times of year (e.g. adults during breeding), and (3) advance our currently poor understanding of combined effects of fisheries and other threats (e.g. climate change, offshore renewables). In addition, research is required on under-studied aspects of fishing impacts: consequences for depleted sub-surface predators, impacts of illegal, unreported and unregulated fishing, artisanal and emerging fisheries, such as those targeting mesopelagic fish, have received insufficient research attention. Some of these shortfalls can be overcome with new tools (e.g. electronic monitoring, remote sensing, artificial intelligence, and big data) but quantifying and addressing fishing impacts on seabirds requires greater research investment at appropriate spatio-temporal scales, and more inclusive dialogue from grassroots to national and international levels to improve governance as fishing industries continue to evolve.

The economic performance of the EU fishing fleet during the COVID-19 pandemic

The COVID-19 outbreak and subsequent public health interventions have depressed demand and disrupted supply chains for many fishing businesses. This paper provides an analysis of the COVID-19 impacts on the profitability of the EU fishing fleets. Nowcasting techniques were used to estimate the impact of the COVID-19 pandemic on the economic performance for the EU fishing fleet in 2020 and 2021. Our results show that the economic impact of COVID-19 on this sector was smaller than initially expected and overall profits remained positive. This was in part due to low fuel prices that reduced operating costs of fishing, and the early response from governments to support the sector. The results vary by fishing fleet, revealing that small-scale fleets and the fleets in the Mediterranean and Black seas have been more impacted than large-scale fleets and the fleets in the Northeast Atlantic.

Ecosystem modeling to evaluate the ecological sustainability of small-scale fisheries: A case study from El Hierro, Canary Islands

This paper examines various fishery management scenarios based on the recovery of small-scale fisheries (SSF) following a submarine volcanic eruption in 2011 in El Hierro Island (Canary Islands, Spain). After this catastrophic event, the SSF composition of La Restinga fishing community was affected by socio-economic and demographic changes. The uncertainty derived from this situation provides an opportunity to evaluate the fisheries’ sustainability and advice on different management options under an ecosystem-based approach. The Ecopath with Ecosim modeling framework was used to build a model of El Hierro Island, where the versatile and traditional multispecies small-scale fleet of La Restinga operates. Our main goal is to improve traditional fisheries, based on the relevance of key local fisheries and multi-specific fishery strategies in the light of scientific knowledge. Temporal simulations for the next decade were analyzed by creating scenarios of alternative fishing effort distributions based on the fishing trends observed in El Hierro small-scale community of La Restinga after a natural hazard. The outcomes of this modeling prototype show the vulnerability of some littoral and demersal species, the resilience of migratory species, and the sustainability of SSF diversification practices. These results could develop an adaptive and co-management strategy with the local fishing community to preserve the small-scale fishing system and marine resources.

Bioeconomics of technological interdependencies in a sequential shrimp fishery: optimal size of the industrial fleet in southern Gulf of California

The bioeconomic sequential externalities in the white shrimp (Litopenaeus vannamei) fishery during 2014-2015 season in southern Sinaloa, Mexico, were analyzed by calculating the optimal size of the industrial fleet (trawlers) given the current oversized small-scale fleet (SSF: cayucos). For this purpose, we constructed a dynamic multi-fleet age-structured bioeconomic model with natural mortality-at-age and catchability-at-age. The distributed delay model was applied to simulate recruitment seasonality. The reproductive effect of seasonal sea surface temperature (SST) was also considered. The constant size of SSF was represented in status quo while reducing industrial fleet by -25%, -50% and -70%Maximizing net present value “NPV” of industrial fleet. The model showed the technological interdependencies of two fleets competing for one species and their respective externalities. The status quo fishery showed a deteriorated biomass (0.27, below MSY); overcapitalized fleet (especially for the SSF); fleets low NPV of resource rent, especially for the cayucos ($761 USD per season). The access limitation of trawlers presented a progressive improvement in all bioeconomic variables, mainly on biomass (+27%) and NPV resource rent for trawlers (+700%). The SSF presented positive marginal externalities (4%). However, biomass was still below MSY (0.34) and the fishery trade-off showed a 70% industrial fleet loss to overcome the negative externalities of the actual SSF status. Given the current conditions of the sequential shrimp fishery (i.e., overcapitalized, overexploited, difficulty to control SSF) the limitation of industrial effort to the area could be a viable strategy to improve the fishery bioeconomic performance. However, it is necessary to explore more management strategies that include the small-scale fishery to attained sustainable levels and higher profitability for users.

Environmental assessment of common octopus (Octopus vulgaris) from a small-scale fishery in Algarve (Portugal)

PurposeCommon octopus is the fishing species with highest economic revenue in Portugal, and its consumption per capita is very high. The majority of catches come from the small-scale fleet with pots and traps. The aims were to assess main environmental impacts of common octopus’ fishery with traps and pots in the Algarve region, where the most important fleet size and landings volume occurs, and to find if there are significant differences between both fishing gears.MethodsThe assessment includes standard LCA impact categories, fishery-specific impact categories, and quantification of macroplastics and microplastics emitted to the environment. The functional unit selected was 1 kg of octopus and the study was a ‘cradle to gate’ system. The scope included fishing operations until the product is landed at the harbour. Primary data was obtained by face-to-face questionnaires from 22 vessels, with an average of 1005 pots and 1211 traps per vessel, and 372 pots and 234 traps lost annually to the environment. Plastic pots have a concrete block and traps are a metal framed covered by plastic netting. Each trap or pot is connected to the main line at regular intervals. Unlike traps, pots do not need bait.Results and discussionFuel contribution to global warming is very high and where the highest potential exists to lower down the carbon footprint. The fuel use intensity resulted in 0.9 L/kg of octopus. The bait used in traps is significant and raises further environmental costs related with fuel consumption. The use of traps represents more than two times the impacts found for pots in all the categories studied except ecotoxicity categories. Zinc use was the main contributor to ecotoxicity categories, but it has not been included in other fishery LCA studies. It was estimated that 12.2 g of plastics is lost to the environment per kg of octopus. The loss of macroplastics from fishing gears was the highest contributor.ConclusionsThe carbon footprint obtained was 3.1 kg CO2 eq per kg of octopus, being lower compared to other seafood products, and less than half compared to octopus caught with trawling. Pots and traps are highly selective fishing gears, causing negligible disturbance to the seafloor. The stock is not assessed, but management measures exist and can be improved. A drawback exists related with gears lost to the environment.

Addressing Gaps in Small-Scale Fisheries: A Low-Cost Tracking System.

During the last decade vessel-position-recording devices, such as the Vessel Monitoring System and the Automatic Identification System, have increasingly given accurate spatial and quantitative information of industrial fisheries. On the other hand, small-scale fisheries (vessels below 12 m) remain untracked and largely unregulated even though they play an important socio-economic and cultural role in European waters and coastal communities and account for most of the total EU fishing fleet. The typically low-technological capacity of these small-scale fishing boats—for which space and power onboard are often limited—as well their reduced operative range encourage the development of efficient, low-cost, and low-burden tracking solutions. In this context, we designed a cost-effective and scalable prototypic architecture to gather and process positional data from small-scale vessels, making use of a LoRaWAN/cellular network. Data collected by our first installation are presented, as well as its preliminary processing. The emergence of a such low-cost and open-source technology coupled to artificial intelligence could open new opportunities for equipping small-scale vessels, collecting their trajectory data, and estimating their fishing effort (information which has historically not been present). It enables a new monitoring strategy that could effectively include small-scale fleets and support the design of new policies oriented to inform coastal resource and fisheries management.

Potential distribution of critically endangered hammerhead sharks and overlap with the small-scale fishing fleet in the southern Gulf of Mexico

Understanding the degree to which fishing operations overlap with the distribution of exploited populations is essential for population assessments and in the formulation of management measures. Here we used ecological niche models to estimate hammerhead sharks’ potential distribution that allowed the first assessment of their overlap with small-scale fishing operations in the southern Gulf of Mexico (GOM). The models were better than random models, with bathymetry as the most important predictor variable for bonnethead shark and average Chl-a for scalloped and great hammerheads. Shallow and intermediate waters of the GOM are of high environmental suitability for bonnethead shark and great hammerhead, and intermediate and deep waters within the continental shelf are more suitable for scalloped hammerhead. The spatial distribution of the small-scale fleet that operates on the western Yucatán Peninsula, southern GOM, had a high overlap with the estimated high environmental suitability of both bonnethead and great hammerhead sharks. We highlight the bonnethead shark, since its coastal habitat preference spans all ontogenetic stages, thus making it highly vulnerable to coastal anthropogenic impacts, including several small-scale fisheries.

Spatial Dynamics Modeling of Small-Scale Fishing Fleets With a Random Walk Approach

The understanding of fishing effort allocation has been recognized as a key feature within the spatial management planning of fisheries. In small-scale fisheries this assessment is challenging because of their multi-specific context. This has resulted in management regulations that do not fulfill their objectives. Therefore, the analysis of vessels movement is needed for the better assessment and management of small-scale fisheries. Thus, we used a Random Walk (RW) modeling approach to characterize the fishing trips of small-scale multi-gear vessels targeting multiple species. We analyzed activities of three different gears (hand net, handline, longline) and two fishing methods (diving, “gareteo”) recorded with a GPS from 156 fishing trips along three fishing seasons (2018–2020) by the small-scale fleet of Yucatan, Mexico. We fitted seven RW models for the movement data and compared their relative and absolute fit through a delta Akaike test and G-Tests respectively. A total of 143 trajectories showed conclusive evidence to establish a CCRW-type movement; the remaining 13 trajectories fit three models (CCRW, TRW and CRW). The Random Walk models were useful for modeling a multi-gear, small-scale fleet operating in southeast Mexico. According to our results, the Composite Correlated Model was the most suitable RW for this fleet. For future studies, we suggest increasing the number of fishing trips and conducting specific studies by gear and fishing method. Also, the application of relative and absolute fit tests to compare the performance of RW models is highly recommended.

Spatio-Temporal Determination of Small-Scale Vessels’ Fishing Grounds Using a Vessel Monitoring System in the Southeastern Gulf of Mexico

In most small-scale fisheries (SSF), there is limited or null information about the distribution and spatial extent of the fishing grounds where the fleets operate, due to the lack of explicit spatial and temporal data. This information is key when addressing marine spatial planning and fisheries management programs for SSF. In addition to technical or biogeographic restrictions, environmental conditions in the area influence the way fishers operate. Making use of data from a pilot Vessel Monitoring System (VMS) project tested in a small-scale fleet in the Southeastern Gulf of Mexico (SGoM), for the first time in the region, we were able to learn what role environmental factors play in the distribution of potential fishing grounds for this fleet. We got tracking information of 1,608 daily fishing trips from vessels operating in four states using the VMS for 7 months. We used a correlative modeling approach to identify potential fishing grounds where this fleet operates along the SGoM, accounting for environmental variables. We assumed that environmental conditions can shape the spatial distribution of species targeted by this fleet and hence influence fishers’ operations. The results indicated that net primary production and sea surface temperature were the main drivers that shape the spatio-temporal potential distribution of fishing grounds in the study site. The approach employed here seems appropriated and opens an opportunity to learn more about the factors that define the spatial distribution of small-scale fleets and their potential fishing grounds.

Length-weight relationships of four finfish commercial species from the southern Gulf of Mexico

The relationship between total length and total weight (LWR) of four commercial species of finfish captured in the southern Gulf of Mexico (Lachnolaimus maximus, Ocyurus chrysurus, Mycteroperca bonaci, and Mycteroperca microlepis) was estimated. Two of these species are captured in the region by the small-scale fleet, while the other two are targeted by small-scale and semi-industrial fleets using harpoons, handlines, and long-lines. For the assessment, the organisms were sampled at the landing decks in the study area in two periods: 1996-1999 (semi-industrial fleet) and from April 2017 to May 2018 (small-scale fleet). A total of 2780 individuals were sampled which 2775 individuals were used to obtain LWR functions. The four species showed negative allometric growth with b < 3 for the 2017-2018 period, two species showed positive allometric growth with b > 3 for the 1996-1999 period. This type of information is an important input for the stock assessment of these species that support important fisheries in the zone and are under high fishing pressure levels.

Fishers as foragers: Individual variation among small-scale fishing vessels as revealed by novel tracking technology

Effective fisheries management requires an understanding of fisher behavior. Though vessel tracking systems are increasingly used to describe the movements and activities of industrial fishing fleets, their use has been limited within the small-scale fisheries employing the vast majority of the world’s capture fishers. Here we combine novel vessel tracking technology with logbook data to conduct a high-resolution analysis of behavior and decision-making within a small-scale fishery. Our results indicate significant heterogeneity in fisher behavior, catch composition, and profits within a small-scale fleet operating in the central Gulf of California, even amongst fishing vessels using similar gear types. The weekly home ranges (75 % Kernel Utilization Distribution) occupied by fishers spanned 1.5–1121.8 km2 across 13 vessels, while weekly profits ranged from -1810 to 26,160 pesos. Differences in the spatial interactions and catch profiles of observed vessels revealed the existence of behavioral associations linked with distinct fishing strategies. After identifying and describing the contextual factors driving such heterogeneity among vessels using hook and line fishing gear, we interpret emergent patterns and processes using insights from foraging theory and marine social science. In illustrating the applications and opportunities presented by recent advances in vessel tracking technology, we argue for the use of spatially explicit analytical approaches in assessing behavioral diversity within small-scale fisheries and in designing robust and equitable management strategies.

A Bio-Economic Analysis of the Liberian Coastal Fisheries

Many coastal fisheries are subject to harvesting externalities due to inadequate regulations compounded by limited enforcement. Coastal fisheries in Liberia consist of a fleet of dugout canoes (Kru) primarily targeting demersal finfish, larger open wooden boats propelled with outboard engines targeting small inshore pelagics (Fanti), and a small number of industrial trawlers employing midwater and bottom trawls targeting finfish and shrimp. This paper develops a bio-economic model for the coastal fisheries in Liberia and employs the model to identify economic optimal fishing effort and harvesting trajectories for the different coastal fleets. The results show under harvesting and disinvestments in the coastal fisheries in Liberia. In 2010 the Government of Liberia declared a six nautical mile inshore exclusion zone accessible only to small-scale fisheries (SSF), which was accompanied by increased enforcement. The coastal fleets in 2016 were profitable but the distribution of profits was tilted to the small-scale fleets. The government needs to evaluate what policy options are available to fully utilize the fisheries potential for different species complexes while at the same time reduce the risk of conflict and overharvesting. There appears to be a need for investment in new technologies, which can only take place if fishing in Liberia will remain profitable.

Participatory research to understand spatio-temporal dynamics of small-scale fleets: The C. bellicosus fishery in Magdalena Bay, Baja California Sur, Mexico

Small scale fishing is one of the main sources of income, food, and livelihoods for coastal communities. Despite this, it is an activity that faces challenges, among others the lack of scientific information about the state of the resources and the operation of fleets both necessary for management/conservation decisions. Magdalena Bay, a region recognized for supporting important fisheries, contributes more than 75% of the production of warrior swimming crab in Baja California Sur (BCS). Therefore, the present study intends to understand the spatio-temporal dynamics of the warrior swimming crab fleets from collaborative efforts with fishers in the generation and interpretation of information. Official catch landing reports database for the period 2001–2018 was used, spatio-temporal data of the fleets operations was generated through GPS data loggers (2015–2018), and the results were validated and complemented through surveys that incorporate local knowledge. The results include the analysis of catch per trip and fishing intensity, which identify more than 6800 fishing grounds and five main fishing areas Los Arenales, Estero Las Tijeras, Isla de Patos, and La Boya. The average indicators per daily operations determined that the best season for the fishing of warrior swimming crab is summer to autumn when 42.3 kg was captured, covering 43.9 km, and 33.6 L of fuel plus 8.9 h were invested. It was found that 51% of the fisher's fish exclusively warrior swimming crab, while the rest alternate their activities with others fisheries such as finfish, geoduck clam, and shrimp. Maps and economic indicators obtained are valuable inputs to reflect on best fishing practices and improvements in management measures in use, with the advantage that these results were obtained with the participation of users, in a transparent way, and consequently improves their use and acceptance.

Growing Into Poverty: Reconstructing Peruvian Small-Scale Fishing Effort Between 1950 and 2018

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 developed several indicators to assess changes in the fishing efficiency and economic performance of this fleet. Segmented regression analysis was used to identify statistically significant breakpoints and changes in their trajectories between 1950–2018. 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.

Longline métiers and associated economic profiles in eastern Mediterranean fisheries: The case study of Kalymnos Island (South Aegean Sea)

The small-scale fishery has a high socio-economic importance in the Mediterranean Sea. This is especially relevant for specific areas that harbor, proportionally, very large part of the fleet, and thus, represent hot spots. Among such areas, Kalymnos Island merits special attention as it harbors the largest and most active small-scale fleet in the eastern Mediterranean. Therefore, the present study analyzes the small-scale longline fishery in Kalymnos, using the métiers approach, to assess its dynamics and evaluate associated economic profiles. A multivariate analysis was used to identify the relevant métiers, by inputting the main resources and fishing gear data that were recorded during landings. Six main practices were observed using set longlines, drifting longlines, handlines and squid jig-lines as fishing gears, and targeting the species Pagrus pagrus, Diplodus vulgaris, Pagellus erythrinus, Sparus aurata, Xiphias gladius, Octopus vulgaris and Loligo vulgaris; the above métiers earned a profit margin. The study revealed the multi-species nature of longline fishery in Kalymnos, and provided baseline information for their associated economic profiles, towards the development and implementation of sustainable management plans.

Interactions of small-scale fisheries in Mexico’s northwest Pacific

In Mexico, as in other parts of the world, there is limited knowledge regarding the operation of small-scale fisheries. Also, there is an urgent need for the diversity of fisheries and their interactions, and the diversity of species to be analyzed on a regional level. In this study, the dynamics of the small-scale fleet operating in San Ignacio in the northwestern Pacific of the state of Baja California Sur were analyzed, recognizing the fishery’s multi-species and multi-gear character and its effect on the spatial and temporal distribution of the fishing effort. The operative units (OU) approach was applied; OUs are defined as the set of associated vessels that exploit one or more target species using similar fishing gears. The information about species, gears, sites and fishing seasons was obtained from interviews with 74 fishers. The OUs identified included: diving-pen shell scallop; diving-squalid callista; diving-Pismo clam; collection-black ark; trap-barred sand bass; trap-crab; trap-lobster; cast net-shrimp; bottom net-fish; surface net-fish; bottom net-shark. The variation in the activity of each OU is related to the availability of the resources, prices of the products and official restrictions. From a management perspective, this method helps to clarify which OUs adhere to specific rules associated with their métier and others, which are less well defined since their OU characteristics are associated with their fishery level. The definition and characterization of the OU, based on the local knowledge of the fishermen, assist the design of management schemes that consider the spatial and temporal complexity of the small-scale fisheries.

Influence of aquaculture on fishing strategies: Insights from Galician small-scale fisheries

Marine ecosystems have been traditionally exploited by coastal communities in several ways, especially by fishing. More recently, aquaculture has emerged as an activity through which coastal communities have diversified their economies. Thus, many regions of the world face the challenge of allowing both activities to maximise their yields while complying with conservation objectives. Our study area represents a paradigm of this reality as intensive mussel aquaculture has expanded in the region since the 1950's, forcing small-scale fisheries to adapt to the new scenario. Using a cross-disciplinary approach, we identified two métiers in the studied fleet: a) one composed mostly of queen scallop catches (Queen Scallop Métier - QSM), and b) a more heterogeneous one with a varied composition of Crustacea, Cephalopoda and Fishes (Mixed Composition Métier - MCM). The MCM is strongly spatio-temporally correlated with mussel raft locations, which indicates how the bottom trawl small-scale fleet has adapted its strategies to the presence of aquaculture. Moreover, the rich community associated with mussel rafts is reflected in the heterogeneous catch composition (of valuable species) of the fishing operations carried out near mussel rafts. However, accumulated biodeposits have attracted detritus feeding non-commercial species, creating a new ecological paradigm and posing operational difficulties for the fleet and higher discards.