Estimating global discards and their potential reduction for the Galician fishing fleet (NW Spain)

This study presents the first comprehensive estimation of discard amounts in the Galician fishing fleet, in order to provide an integral view of this increasing environmental problem at a regional scale. Subsequently, a series of improvement actions relating to discard minimization are suggested with the goal of enhancing the performance of the Galician fishing fleet through discard minimization. Discard estimates were constructed individually for the different Galician fisheries by aggregating primary data obtained from a total of 89 fishing vessels and secondary data for those fleets that were not directly sampled. Results showed that roughly 60,250 t of marine organisms were discarded by the Galician fleet in 2008, representing 16.9% of the total capture. Moreover, an important percentage of these discards were linked mainly to trawling vessels and to a lesser extent, to certain long lining fisheries. Therefore, improved management measures in target stocks should take into account the fact that alternative fishing gears other than trawl nets may reduce the amount of discards for certain species. This estimation may improve the assessment of stocks and help to quantify the damage that discards may have on wild ecosystems.     

Changes in fishing behaviour of two fleets under fully documented catch quota management: Same rules,different outcomes

A Dutch pilot study of fully documented fisheries provided the opportunity to observe actual changes in fishing behaviour under catch quota management (CQM). Interviews with fishers in the pilot study aided in interpreting the results and giving insight in the decision making process and reasoning of fishers. The CQM pilot study entailed a fleet of small and large demersal vessels. For these vessels, all cod catches were counted against quota, including catches of individuals below minimum landings size. To obtain reliable catch data all vessels were equipped with electronic monitoring (EM) systems. These systems recorded videos of all fishing and processing activities on board. In return, fishers received a 30% quota bonus for cod and were compensated with more flexibility on effort regulations. It was hypothesized that vessels in the CQM will (i) increase their landings by 30% according to their quota bonus, (ii) increase the use of gear with large mesh size, and (iii) change effort towards fishing locations with high catch rates of large cod and avoid areas with high catch rates of undersized cod. The results showed that CQM had no effect on fishing behaviour of the small vessels. In contrast, large vessels significantly increased their cod landings (216%) and avoided undersized cod. This difference in response of different fleets suggested that implementation of CQM, for instance in the context of the European Common Fisheries Policy, should consider fleet characteristics. It seemed that larger vessels in this study more easily adapted their behaviour to new management regimes and that the quota bonus opened up new fishing strategies, that were not envisaged during the implementation.     

History,effort distribution and landings in an artisanal bottom longline fishery: An empirical study from the North Atlantic Ocean

Commercial fishing data were used to reconstruct historical spatio-temporal patterns of fishing effort and landings in the bottom longline fishery of the Azores. Key events during an important 15-year period were charted, through fisher interviews together with GIS analysis. While effort distribution varied over time, the prevailing pattern was a shift in focus from eastern to western areas and from shelf/slope to offshore banks and seamounts in response to policy measures (e.g. banning bottom longline inside 3 NM, public aids for modernization of the fleet) and reduced fishing yields. Areas 12–50 NM from shore represented the most vital fishing grounds in terms of fishing effort and production. Declining landings of the major demersal species, in recent years, indicate that present catch levels are not sustainable and further measures need to be taken in order to sustain fisheries resources. Knowledge of fleet behavior and the distribution of fishing effort, particularly in patchy environments, provide valuable insights into the impacts of past management decisions and help predict the outcome of new policies both in this region and elsewhere.     

Application of a vessel monitoring system to advance sustainable fisheries management—Benefits received in Taiwan

Vessel monitoring systems (VMS) are considered important instruments for fisheries monitoring, control and surveillance (MCS) to reverse the current depressed state of the world’s fisheries, and have been mandated worldwide by fishery management agencies. The essential function of the system is to provide near-real time vessel position; the potential applications could, however, be more than that. This study explores the additional benefits, with practical examples, that Taiwan has received from implementing the system: in improving the quantity and quality of logbooks recovered, obtaining access to fishery-independent fishing effort estimates and prompt catch/effort reporting, enabling the possibility of regional management and understanding of both fleet dynamics and vessel behavior, and increasing efficiency of vessel safety protection. For other distant-water fishing nations, Taiwan’s experiences serve to demonstrate how the application of VMS technology can advance sustainable fisheries management.     

Fishing strange data in national fisheries statistics of Greece

Fisheries statistics provided by the Hellenic Statistical Authority (HELSTAT) have been often criticized for unusual estimates in landings and fishing effort data and for limitations in the sampling methodology, although there is no study on the identification of these biased and misreporting estimates. In the present study the landings per species and fishing subarea, as well as the fishing effort data per fishing gear reported by HELSTAT were analysed over the period 1982–2010. The results showed abrupt changes of both the recorded species and species landings per subarea, spurious correlations of landings among different species groups and misreporting estimates in the number of fishing vessels per fishing gear. These might be likely attributed to: (a) differences of the HELSTAT administrative infrastructures at local scale, (b) changes in the sampling protocol followed by HELSTAT, (c) reporting faults made by HELSTAT, (d) fisheries restrictive measures at local basis, (e) other factors that increased the bias and the uncertainties of HELSTAT fisheries data and related to socio-economic (i.e. fuel price) and operational (i.e. spatial structure of the fisheries fleet) aspects and/or (f) to environmental changes that might possibly affected fisheries dynamics. The present study aims to the improvement of the effectiveness of the national fisheries statistics as pinpointed by Common Fisheries Policy in order to avoid imprecise and/or biased estimations about the state of the fisheries.     

A transition beyond traditional fisheries: Taiwan's experience with developing fishing tourism

Transforming fisheries into tourism has become a global trend. It arises mostly due to a decline in income generated by traditional fisheries, and fishers thus turn to seek alternatives by engaging in marine tourism activities. Taiwan has practiced this transformation policy for more than two decades, and fishing tourism has developed as a major outcome. This paper aims to investigate Taiwan's experience with developing this activity, with an emphasis on the emerging concerns it faces and anglers’ perception of trip quality and potential management measures. The results show that anglers had a general satisfaction with the service delivered by operators. However, concerns regarding sustainable development of this activity were identified, mostly involving ineffective enforcement of regulations against illegal fishing, conflicts of interest between commercial fishing and recreational fishing, lack of statistics on harvest, improper angler behavior, and competition from yachts. Lastly, management implications for sustainable fishing tourism were discussed, highlighting suggestions to alleviate the concerns, including strengthening management of the harvest, encouraging dialogue between commercial and recreational sectors, enhancing marine environmental stewardship among anglers, and improving coordination of management to create a fair and balanced environment for recreational fishing vessels and yachts.     

Adaptation in a time of stress: A social-ecological perspective on changing fishing strategies in the Canadian snow crab fishery

Recent scholarship has focused attention on the dynamics and management of marine social ecological systems and on the need for developing a deeper understanding of the fishing strategies of fish harvesters. This includes an understanding of how a broad range of factors influence the strategies of those at the ‘center’ of marine social-ecological interactions. This paper reports on the findings of a survey of snow crab (Chionoecetes opilio) fishers in Southeastern Labrador conducted at a time (2005) of significant stress in the fishery. Results highlight that snow crab fishers are embedded in a social-ecological system and that shifts in fishing strategies in times of stress are a product of adapting to a dynamic, interactive set of factors that have social, economic, ecological and management aspects. Important differences between fleet sectors (larger and smaller vessels) as well as processes of learning are also described. The article concludes with a discussion of the implications for management and the utility of a holistic social-ecological perspective.     

Investigation of strategies to improve the recycling effectiveness of waste oil from fishing vessels

The marine ecological environment and fishery resources can be severely polluted or destroyed by waste oil from fishing vessels if they are emitted directly into the ocean without any proper pre-treatment process. International conventions such as MARPOL 73/78 regulate waste-oil emissions and require the installation of a waste oil–water separator only for ocean-going ships of over 400 gross tons. Hence, these international conventions are not applicable to most fishing ships due to their low gross tonnages. In addition, space on most fishing vessels is too limited to allow waste-oil storage tanks or a waste oil-water separator to comply with international maritime regulations. Because a significant amount of waste oil is produced by fishing vessels around the world every day, effective strategies or measures are needed to prevent this waste oil from polluting the marine environment. This study thus investigates strategies and measures for improving the effectiveness of waste-oil collection from fishing vessels. This study found that existing procedures for the collection and treatment of waste lubricating oil on land could be applied to the management of waste oil and bilge water from fishing vessels. Sufficient oil–water separators and storage facilities for the collection of waste oil should be placed at each fishing port and shipyard. Fishermen should then be required to deliver their waste oil to these storage facilities, from where it can be transported to legal recycling companies for further treatment. In addition, fishing harbor authorities should bear definitive responsibility for monitoring the illegal dumping of waste oil and for checking the waste-oil record books of fishing vessels. Each maritime country should enforce relevant laws and regulations to reduce the emission of waste oil from fishing vessels into the ocean.     

Capacity and economic efficiency in small-scale fisheries: Evidence from the Mediterranean Sea

To design an effective capacity management plan for small-scale fisheries one must understand what one is measuring and define its capacity. As recognized by some authors, overcapacity is a problem that generally affects small-scale fisheries just as much as it does other types of fishing. This study aims to estimate fishing capacity, technical efficiency, scale efficiency and capacity utilization in a particular small-scale fishery in the Mediterranean, i.e., the Northwest Sardinian fleet in Italy. A non-parametric approach using a data envelopment analysis (DEA) model was applied to a sample of trawls in order to estimate their economic capacity, and related measurements were taken. The capacity and efficiency with reference to two different alternative scenarios were also calculated.     

The artisanal fishery of Cynoscion guatucupa in Argentina: Exploring the possible causes of the collapse in Bahía Blanca estuary

Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources.     

Nuts and bolts in fisheries management—a technological approach to sustainable fisheries?

According to the Food and Agriculture Organization of the United Nations, overcapacity in the fishing fleet poses a fundamental challenge in fisheries. Overcapacity leads to an increased pressure on fish stocks and a decrease in economic profit. The fishing fleet is marginalised economically, and overcapacity creates allocation conflicts between different gear and vessel groups. In addition, the expenses to control and management increase. Although Norwegian authorities have introduced several restrictions, for example total allowable catch, licenses, vessel quotas, and other regulatory measures, this article shows that the problems connected to overcapacity persist. Analyses of the technical capacity development show that there is an overall capacity expansion although the number of vessels is reduced. This development is an indicator of the dynamics of technological development over time, and the article discusses whether the concept of technology is sufficiently integrated into fisheries management. The important question now is whether analyses of the technical capacity development can serve as a positive supplement to the traditional fisheries management, which largely is based on input from the scientific disciplines biology and economics.     

Mapping fisheries in the German exclusive economic zone with special reference to offshore Natura 2000 sites

Large intensity and diversity of human activities result in an increase in complexity in the utilization of space. This paper describes the fisheries and a method to map fishing efforts and catches of different fleets by combining vessel monitoring system (VMS) data and logbook data. The method makes it possible to explore the spatial and temporal variability of fishing and the potential impacts of proposed management measures on the fisheries. The method is proposed to be used in the development of management plans for marine protected areas such as Natura 2000 sites, designated to protect vulnerable habitats and species.     

Responses of the fishing sector to transitional constraints: From reactive to proactive change,Yucatan fisheries in Mexico

Most fisheries management studies have concentrated on understanding resource dynamics and have paid less attention to understanding the dynamics of those who use the resources. This situation limits the knowledge about the fisheries system as a whole and specifically about the viability of management schemes. It is vital to understand how the actors within the fishing sector (fishing firm owners/managers, fishers, fisheries managers, and traders) may respond to changes in fishing resources trends, market dynamics, and fisheries policies before they are implemented. These issues are explored in this paper by applying a longitudinal analysis of the Yucatan Mexico's fishing industry. The analysis is presented within the framework of the theory of change and coping strategies. The study primarily involved interviews during 2008 with the main owners of companies in the fishing industry and with fisheries managers and other stakeholders. Time-series catch data on the main fishing resources are also reviewed to evaluate changes across three historical periods and describe how the actors have perceived and responded to those changes. Given conditions of uncertainty in resource availability, changes in market demand and changes in institutional arrangements, the viability of traditional business and resource management practices are discussed. The analysis presents different kind of triggers that have modified the conditions of the fishing sector and had had impacts on the socio-economic–ecological system in which fisheries are embedded. The need for adaptive strategies in the whole chain of the fisheries business and resource management is stressed, given the current changes and conditions of fisheries. The discussion states a series of actions that could improve the relationships between business practices and fisheries management.     

Spatial management of small-scale fisheries on the west coast of Baja California Sur, Mexico

To understand small-scale fisheries in Mexico, the spatial and temporal distribution of the landed catch of several species was analyzed, including abalone, clams, snails, octopus, squids, lobsters, shrimps, blue crabs, sharks, rays and finfish along the 349 km of the Gulf of Ulloa coast. Data reported by fishers from 1998 to 2009 on catch volume and value per group of species and per fishing locality, together with the number of landing events, were used to define fishing zones and the relative importance of each fishery. Finfish turned out the primary fishery in the region, but the other fisheries showed relevant spatial changes that should be considered when establishing management goals and fishing regulations according to resource availability, fleet efficiency, processing capacity, commercialization of fishing products and profit distribution.     

Measures of fishing fleet diversity in the New England groundfish fishery

After 16 years under a limited access program with effort controls, the New England groundfish fishery transitioned to a catch share management system in 2010. For much of its earlier management history, issues related to fishing capacity were paramount as effort controls were increasingly restrictive to meet biological objectives. As the size of the active fleet declined from over 1000 vessels from 1994 to 2001 to less than 400 vessels in 2012, the management concern shifted to fleet diversity. Fleet diversity has been cast in terms of vessels based on characteristics such as size, gear, and region rather than their share in landings or economic value. Measuring fleet diversity with indices commonly used in the biodiversity literature such as richness, effective diversity based on the Shannon index, and evenness appears appropriate for this context. In this paper these indices were applied to measure changes in diversity of the active New England groundfish fleet from 1996 to 2012. Fleet diversity as measured by the Shannon Index has declined by approximately 35% from 1996 to 2012, but has remained relatively stable since 2007. Forty vessel types were present in all 17 years, which accounted for about 85% of active groundfish vessels and over 90% of total groundfish landings in all years. Even though the fleet size and overall diversity have declined the “core” groundfish fleet remains stable.     

Discrete choice modelling of fisheries with nuanced spatial information

Temporary marine area closures or more permanent Marine Protected Areas are being proposed as potential options in ecosystem-based marine spatial management. These policy options are known to displace fishing effort. In this paper, EU Vessel Monitoring System (VMS) data is combined with other site and vessel information and used to model the fishing site choice decision of Irish demersal otter trawlers. Uniquely, the fishing ground options used in the analysis reflect the actual seabed contours trawled by the fleet. The fishing site choice model, based on this natural site definition is compared to an alternative destination choice model where the fleet decision is specified using a grid based site definition as employed in previous work. It is argued that the natural site specification is a more realistic specification of the fisher site choice decision. Using the preferred natural fishing site choice model, a policy scenario involving the hypothetical closure of one of the fishing ground options is then simulated to examine the possible redistribution of fishing effort.     

Forecasting bivalve landings with multiple regression and data mining techniques: The case of the Portuguese Artisanal Dredge Fleet

This paper develops a decision support tool that can help fishery authorities to forecast bivalve landings for the dredge fleet accounting for several contextual conditions. These include weather conditions, phytotoxins episodes, stock-biomass indicators per species and tourism levels. Vessel characteristics and fishing effort are also taken into account for the estimation of landings. The relationship between these factors and monthly quantities landed per vessel is explored using multiple linear regression models and data mining techniques (random forests, support vector machines and neural networks). The models are specified for different regions in the Portugal mainland (Northwest, Southwest and South) using six years of data 2010–2015). Results showed that the impact of the contextual factors varies between regions and also depends on the vessels target species. The data mining techniques, namely the random forests, proved to be a robust decision support tool in this context, outperforming the predictive performance of the most popular technique used in this context, i.e. linear regression.     

Apparent changes in the trophic composition of world marine harvests: the perspective from the FAO capture database

Almost 50 yr of global multispecies harvests are represented in the FAO capture production database, and offer a broad perspective on events that underlie the major observed changes in global marine harvests. The likely relevance of top–down and bottom–up trophic interactions, versus the impacts of changes in fishing technology and markets on the trophic level of landings, are discussed on a regional basis. Despite the low resolution of this global data set, several common features emerge. Rapid increases in fleet size and technological advance, and imperfect fisheries management measures, are probably responsible for declines in peak multispecies production in many areas since the 1970s, and internal evidence suggests that peak production is not far away in the remainder. Staggered dates of peak landings in different world areas seem to reflect the spread of industrial fishing fleets from `core areas’ to the rest of the world's oceans, which largely took place from the 1960s to 1990s. A general move to higher exploitation of piscivores in global landings is implied in some areas. The hypothesis that top–down removal of predators is affecting lower trophic production is however only one explanation for declining mean trophic levels, and is more likely to emerge from local food web studies. In some regions an increased proportion of short-lived invertebrates in harvests later in the time series supports a move downwards in trophic level targeting. In the North Atlantic and some other areas, fishing down marine food webs may be a likely cause of the increase in landings of shelf planktivores. A shift from depleted apical resources to species lower in the food web may have been made on economic grounds however, independent of possible effects of a release of predatory pressure. Sharp increases in planktivores later in the time series show up in the Eastern Central Atlantic and in the Southeast Pacific and do not appear to be primarily related to depletion of predators. They seem to reflect intermittent strength of upwelling systems, and hence bottom–up effects on food web production, together with changes in harvest technology. For some areas, piscivore landings increased later in the time series than those of planktivores. In the Mediterranean, this seems mainly a bottom–up response to increased marine productivity associated with land run-off and consequent improvements in predatory foraging. In some tropical areas, later increases in piscivorous landings mainly result from expansion of distant water tuna fleets, and are probably unrelated to exploitation of forage fishes. The technological revolution of the 1950s and 1960s involved rapid application of synthetic fibres to improved gear. This led to large-scale mid-water trawling and purse seining by industrial fleets and has especially increased vulnerability of small pelagic stocks over the last few decades. This appears mainly responsible for the apparent decline in mean trophic level of harvests in areas with large stocks of these resources. From an analysis of variances of the sample data set, `Punctuated equilibrium', involving actual changes in ecosystems, rather than just continuous change in the relative harvest rates of species in a given ecosystem, is suggested as an important phenomenon, reflecting both ecological change and changing exploitation strategies.     

Transferable Fishing Concessions (TFC): A pilot study on the applicability in the Mediterranean Sea

Fisheries management systems based on Transferable Fishing Concessions (TFC) and similar rights-based systems have been developed during the last decades in some European countries. However, at present there is not a clear view on the possible effects caused by the application of this management systems in the Mediterranean Sea. The current study, involving nine Geographical Sub-Areas (GSAs) of the Mediterranean Sea, focuses on the appropriateness, transferability and modes of applicability of a TFC system in the Mediterranean area. Three different scenarios of quota allocation have been analyzed by taking into account biological, ecological, environmental, economic and social aspects: quota in terms of resource quantity, quota as a portion of the total fishing time, quota as a portion of the total fishing capacity. Results show that the transferability of a TFC-based system to the Mediterranean context appears to be low due to the characteristics of the Mediterranean fisheries (multispecificity of resources, fishing grounds shared among different countries, multigear, importance of small-scale fisheries) and to the general lack of sound and reliable individual historical data. The study also highlights rights-based systems such as Territorial Use Rights in Fisheries (TURF) might only be applied for the exploitation of sedentary resources, such as clams. A management system based on TFC could be theoretically reasonable for anchovy fishing, where a few species are caught, even if all countries and stakeholders should be involved in the decision making process.