Despite their socioeconomic importance in many coastal communities, European artisanal fisheries have traditionally received less interest than industrial fisheries in marine and fisheries sciences. In fact, they, play a fundamental role in terms of human and territorial development at a local-regional scale [1] - [4] . In Spain, many studies have outlined that artisanal fisheries are suffering from a heavy decline in recent times [5] [6] . Although the high heterogeneity of these activities across different South-European countries and regions has impeded so far a standardized definition of these fisheries¹ [2] [7] - [9] , most of them are characterized by a high diversification in gears and fishing techniques and changing spatio-temporal patterns of their use. These features make difficult artisanal fishing management [2] [10] - [12] .

In such a complex context, the concept of métier has been traditionally used to describe and characterize fisheries, as it is able to capture the major part of their heterogeneity [13] - [15] . Métier has been defined by European Decision 2008/949/CE² as “a group of fishing operations targeting a similar (assemblage of) species, using similar gear, during the same period of the year and/or the same area and which are characterised by a similar exploitation pattern”. Therefore, the concept of “métier” is closely linked to the fishing activities, patterns, traditions and gears employed by artisanal fishermen: each métier gathers a group of fishing operations defined by the combination of fishing gear, target species, area and season [11] [16] , making up homogeneous units that summarize in a single variable the main characteristics of a large number of fishing trips [17] .

As a consequence, a métier-based approach is very useful for understanding the spatio-temporal patterns of fishing effort allocation and resulting catches [10] [11] . Moreover, technical and bioeconomic characterization of fishing métiers is a basic step to accurately assess the real fishing effort and pressure exerted by artisanal and small-scale multi-specific fisheries. This understanding constitutes a key step for the improvement of economic and ecosystem fisheries management, as it helps to select appropriate management strategies and measures [12] [18] [19] , and provides basic information to address marine spatial planning concerning artisanal fleets [20] .

As Forcada et al. [10] have already acknowledged, identification of métiers has been widely based on the analysis of large historical datasets on species composition or catches data [17] [21] - [27] . The problem arises when such information is not available for artisanal fisheries. Recent research projects addressing métiers identification or applying a métier-based approach in the South-European area constitute illustrative examples of these limitations. On the one hand, the IBERMIX Project [28] was aimed at redefining and providing métier-disag- gregated fishing data for the Spanish fleets operating in the Atlantic Iberian Peninsula waters oriented to ICES assessments and STECF mixed-fisheries management; as the segmentation was based on logbooks data, small- scale fleets were excluded from the analysis³. On the other hand, the TECTAC Project [29] has been aimed at addressing and supplying fisheries managers with a modelling tool to evaluate the impact of regulations on the dynamics of fleets and fishing mortality, on the basis of fishing tactics and strategies identification by métier. To do so, 30 demersal fleets from Denmark, the United Kingdom (England), the Netherlands, France and Spain were investigated, but in almost all the cases, vessels chosen for the project registered total length ranges above 10 - 12 metres, as well as a weak representativeness of so-called small-scale fisheries⁴.

In many cases identification and characterization of artisanal métiers have been carried out based on alternative approaches such as onboard samples or surveying methods [10] [11] [30] - [32] , although researchers have also pointed out reliability problems that may arise when data elicited from resource users are employed [33] . Nevertheless, there is no precedent in exploring the potential of other sources of information to identify and characterize poor-data artisanal fisheries, as for example the administrative registers of fishing licences used by artisanal vessels: in many South-European coastal regions, artisanal vessels are required to communicate to fishing Administration each daily change in the fishing gears they used (equivalent to different artisanal fishing licences), so that it supplies an interesting source to be applied in monitoring their activity.

All these things considered, the main objective of this study has been to carry out a detailed and updated characterization of the main technical, biological and economic issues concerning the métiers used nowadays by the artisanal fishing fleet of Asturias, an Atlantic region located in Northwest Spain. To reach this goal, a novel approach using administrative data on fishing licenses combined with daily sales registers and information collected through a surveying process has been applied in order to: i) identify and classify the artisanal fishing métiers performed by the aforementioned fleet, ii) characterize their main technical, bioeconomic and temporal patterns, iii) provide basic information to improve decision-making processes and iv) discuss the relevance of the findings for the design of specific sustainable management measures in the context of South-European artisanal fisheries.

The present study has been part of a wider project about artisanal fishing fleets of the European Atlantic Arc (“PRESPO: Sustainable Development of Atlantic Arc Artisanal Fisheries”), developed between 2009 and 2012 within the Atlantic Area Transnational Cooperation Programme 2007-2013.

The structure of this article is as follows. Section 2 describes the case study and summarizes the data collection process, explaining the main characteristics of data sources used and the methodology applied, in order to identify and characterize the métiers. In Section 3 results are presented addressing the following topics: métier identification and classification, level of activity/use, alternation and seasonality, target species and species composition, weight and incomes per daily sale bill and, finally, technical and workforce demands associated to each métier. Last part of the article includes a chapter of discussion (Section 4) about the main results achieved linked to artisanal fisheries management and remaining constraints that need further research and a section. To conclude, Section 5 shows the main conclusions.

The concept of artisanal métiers actually embraces a highly diverse group of fishing modalities practiced by multi-gear vessels with a high variety of fishing operations, landings, incomes and spatio-temporal patterns. Many South-European artisanal fleets are mainly integrated by vessels under 12 and 10 metres of total length¹⁸; according to Regulation (CE) 1224/2009, these vessels are no subjects to comply with VMS and logbooks fill-in requirements respectively, which derives in a lack of monitoring systems that provide accurate, reliable and quantitative information on spatial and temporal fishing patterns for most of artisanal vessels¹⁹. This situation

^an = 14,254 (13,766 for crew members’ analysis); d.f., degrees of freedom; F, F-Ratio, P, level of significance (^***p < 0.001). A dash (-) indicates no transformation.

has traditionally complicated a sustainable management of these boats, as basic and detailed data on their activity is not available. Usually in this context, first-sales notes become the only systematic source of information, although it allows analyzing neither spatial issues nor duration of fishing operations, so fishing effort and its location are mainly unknown for these fleets. On the other hand, information from specific monitoring surveys on vessels less than 12 metres of total length and voluntary collaboration of fishermen in data collection processes also represent an interesting complementary data source for artisanal vessels, but with important limitations (lack of accuracy and reliability of quantitative information, spatial information mainly qualitative and poorly detailed, etc.). Although some research projects, as IBERMIX [28] or TECTAC [29] have addressed the problem of identifying métiers in the South-European area, the aforementioned limitations on fishing data concerning vessels less than 12 metres have excluded most of artisanal boats from these relevant analyses so far.

This situation has traditionally hampered the design and implementation of specific management measures based on a good knowledge on the characteristics and problems of each métier. At the same time, South-Euro- pean Atlantic regions as Asturias are registering a progressive disappearance of artisanal métiers with low economic profitability (although with high level of environmental and social sustainability), in parallel to a concentration process of artisanal fishing activities on a few main métiers.

Although previous studies also used the information from daily sales and direct interviews to fishermen in order to identify métiers [3] [10] [18] [24] [26] [32] [38] - [40] , this research proposes a methodological novelty based on the detailed monitoring of the regional administrative register of artisanal fishing licences used per day and vessel in the region of study. A value added of this approach, in poor-data contexts, is that it allows reaching a highly-disaggregated and detailed artisanal metier identification and classification, that comprehends all the richness and diversity of métiers practiced by these type of boats, and provides higher resolution than other classification frameworks as the European Data Collection Framework (DCF-2008/949/EC).

Data mining of daily changes in fishing licences used by the artisanal regional fleet presents analytic advantages linked to the richness and high level of detailed data (per day and vessel) recorded, that avoids the lack of precision frequently derived from fishermen interviews and provides a large panel of accurate information that allows a quick preliminary identification of the most important métiers, as well as their main characteristics in terms of target species, fishing gears, monthly temporal pattern and level of rotation. After that, complementary information from daily sale bills, official fleet census and interviews was used to check, adjust and extent results in terms of catches retained for commercial purposes (species composition and weight), incomes, technical demands and fishing strategies per métier.

Although a precedent study carried out by Punzón et al. [41] provided a basic description of the artisanal fisheries in this area, it was focused on fishing gears, catches and their seasonality using information dated in 1996. From an empirical point of view, the present study provides an in-depth and updated characterization of the metiers practiced by the artisanal fleet in the region studied (Asturias, Northwest Spain), with high level of resolution and showing how artisanal activity is changing in recent times (trend of concentration in some métiers and cease of another).

The Asturian fleet is mainly artisanal, involving over 230 vessels (205 vessels with sales in 2009) that represent around 70% of the whole fleet. This sector has a great socioeconomic, cultural and historical importance given the strong bonds between the coastal communities, the artisanal fisheries and the marine environment [1] - [4] [12] . The large number of métiers identified in this study (21 métiers, 16 of which were active in 2009) is a direct consequence of the coastal, close-to-port character of the Asturian artisanal fisheries. As several studies have highlighted, the use of fixed fishing gears in coastal areas, where seasonal environmental variability and spatial heterogeneity are high, promotes the diversification of fishing tactics [10] [11] . Results from this case study confirm the real heterogeneity of vessels that usually are grouped together within the same category (named “Artes menores” in Spain, “Only passive gears” at a European scale, etc.), which is treated as a “uniform” census modality by management and planning public policies. As a consequence, in those regions where artisanal vessels belong to these census categories and represent a relevant part of the total fleet, management measures should be designed and implemented taking into account métiers heterogeneity and the high level of internal complexity of artisanal fleets.

As it occurs in another artisanal and small-scale fisheries in South Europe [10] [11] [31] [32] [38] [39] [42] , findings concerning the high annual rotation of fishing métiers and gears types confirm that polyvalence and versatility²⁰ are important features of artisanal fleets, representing the fishermen’s ability to adapt, up to some extent, to dynamic environmental conditions and to different presence of resources in order to ensure stability in landings and sustain returns throughout the whole year.

Two interesting conclusions arise from these findings. Firstly, when métiers rotation exists, a certain degree of “substitution effect” among métiers exists, which must be interpreted as a strength and taken into account for artisanal fleets subsidies design; in these cases, a percentage of negative effects from changes in fish stocks, limitations of captures or increases in costs can be softened. In opposition to this, the practice of métiers with low possibilities of replacement among each other introduces rigidity in fishing strategies and reduces adaptation possibilities for the fleet, which should be considered by managers. This research has confirmed that some smaller vessels have constraints to redistribute their fishing effort, especially in those periods of worst weather conditions: some artisanal métiers identified, as the glass eel fishing, and other fishing activities as the goose barnacle (Pollicipes pollicipes) recollection, play a fundamental role as alternative fishing activities during certain periods when it is difficult and unprofitable to carry out another métiers (i.e. first months of the year when longlines use to be inactive because of bad weather conditions). In terms of sustainable management of artisanal fisheries, this kind of métiers should be prioritized by sectoral support measures, as they have strong socioeconomic effects at a local scale, play an important subsidiary role in such periods (when other métiers cannot be practiced) and contribute, as a result, to the stability of artisanal fishermen revenues along the year.

Nonetheless, despite their polyvalent character, certain métiers are used extensively by the artisanal fleet producing the major part of landings and revenues of these vessels: Lophius trammel net and Merluccius longline generates the 28.6% of landings and 43.1% of the total income generated by artisanal fisheries in 2009. It is worth highlighting that trammel net is one of the most representative artisanal gears across European small-scale fisheries [2] [10] [11] [32] [39] [40] [43] - [45] . However, while most Mediterranean trammel nets artisanal métiers target species such as scorpion fishes (Scorpaena spp.), red mullets (M. surmuletus), European hake (M. merluccius) or cuttlefish (S. officinalis), the trammel net mostly used by Asturian artisanal vessels target mainly Lophius spp. and Raja spp., although landings of M. surmuletus and M. merluccius are also recorded. Identified Mullus trammel net and Merluccius gillnet are also widely used by the aforementioned Mediterranean artisanal fisheries.

On the other hand, although the use of longlines have been reported for several Mediterranean fisheries [10] [11] [38] [46] targeting mainly sea breams (Sparidae), their degree of use is clearly lower than shown for the Asturian artisanal fleet (used in 28.63% of the total fishing days). This specific gear targeting European hake (M. merluccius) and conger (C. conger) seems to be more common among Atlantic artisanal fisheries [47] .

In terms of spatial distribution, the identified métiers are located in several fishing ports covering broad geographical areas. In fact, 12 of the active métiers (75%) are present in 7 or more different fishing ports. These results contrast with those concerning artisanal fisheries of SW Spain [26] , where the identified métiers are located in a few fishing ports. In Asturias, only those traditional métiers carried out in shallow waters close to the shore and targeting mainly crustaceans and anguilliformes (Anguilla pot and glass eel fishing) are restricted to some specific locations: these métiers (mostly traps) also present the highest seasonal pattern (whereas most of the net and longline gears are used during larger periods of the year), so specific appraisals must be carried out in case of Marine Protected Areas declaration or catches limits setting (TAC’s, resource exploitation plans, etc.) affecting them, as negative impacts and economic losses at a local scale may be important.

Analyses of vessels’ typologies have confirmed the existence of significant differences in terms of technical characteristics among vessels depending on the performed métiers. Although other South-European regional studies have found out that métiers are independent from vessel’s size [32] , some other have highlighted the existing relationships between vessels’ size, other technical characteristics and the type of métiers used by small- scale boats [10] [11] [48] [49] . Findings in this research are in line with these studies and stress out that smaller vessels may be limited to exploit relatively seasonal fisheries surrounding the home ports, especially between January and March when adverse weather may put boats at risk. In addition to this, specific results on technical demands in this study provide researchers and managers useful information to carry out more accurate inferences about costs structures and output models for artisanal fleets, taking into account the technical demands of each métier. In terms of public policies design and budget provision, they help to assess up to what extent each métier is sensitive and need support from subsidies, training activities or security and qualification requirements.

Artisanal vessels have to decide on the métiers’ choice in two time scales: daily (short-term) and annually (long-term), when they have to make investments in fishing gears. As it has been underlined by Tzanatos et al. [11] , in the short-term, the choice of fishing tactics or métiers depends on multitude of factors: recent yield and income, market demand and price, seasonal availability of fishing grounds, tradition, skippers’ experience, rumors about other fishermen yields, etc. Hence, changes in the biological or economic conditions results in a rapid redistribution of the fishing effort of artisanal fisheries [50] , as it has been also shown in this case study throughout the high alternation between different métiers and gear types along one fishing season. Although the average landings weight was 99.19 kg and the average income was €396.65 per sale bill in 2009, Asturian artisanal métiers showed significant differences: the rod-hook targeting Scomber scombrus is the métier that generates the highest weight (1468 kg) and income (€886), being also important the Merluccius longline and gillnet métier (an average income of €434 and €425 respectively per fishing day) and the Lophius trammel net métier (€423), whereas 50% of Asturian active artisanal métiers registered an average income per fishing day under €350 in 2009. These results provide useful information that could guide artisanal fisheries managers and decision makers in the future allocation of ITQ’s or the current distribution of TAC’s, as well as they constitute valuable data to assess potential losses (and compensation measures) for vessels affected by certain management measures or environmental disasters.

These findings reflect that annual fishing effort is distributed among an “optimal” combination of métiers for each vessel, according to boats characteristics, expected annual profitability and fishing possibilities in the area, given the existing regulatory framework, so there is some margin of flexibility to adapt fishing decisions to changes in fish stocks, limitations of catches or increases in costs. This information constitutes a valuable baseline for further research focused on the assessment of multi-output models and productivity magnitudes, or the modeling of fishermen profit maximization.

The long-term decisions, what can be considered as fishing strategies, are affected by different considerations. As it was revealed in this case study, artisanal fishing patterns within Asturian fleet are changing significantly in the last years, and some of the identified métiers are nowadays in disuse or barely employed. Although the final choice of available gears may be limited by the lack of experience in some of them [51] , ship-owners face mainly a cost-benefit question regarding what would be the best investment in fishing gears. Answers obtained through the interviewing process have shown that the diversity of métiers performed by the Asturian artisanal fleet nowadays are being reduced and tend to concentrate in those ones with higher net profit rates: as García- de-la-Fuente et al. [12] have recently shown, the estimated profitability of nets clearly surpasses hooks, lines and traps artisanal métiers incomes. As an example, ship-owners have stated that despite that high yield and income traditionally generated by longlines, the bait costs have increased greatly over the last years, pushing down the final profitability of such métiers. As a consequence, many vessels have recently invested in trammel net gears (Lophius trammel net) as they present relatively lower exploitation costs. It constitutes a clear example of how fishing tactics and effort may vary over time, which suggests a new sustainable management challenge: it must be evaluated the social and environmental role of artisanal métiers with low economic profitability in order to support them through the current fishing policy. At the same time, environmental sustainability of artisanal net métiers should be increasingly monitored, as they are becoming more and more used.

Two final issues arise from these results. On the one hand, public authorities and fishing guilds should pay special attention to find and implement management and commercial/diversification strategies to support those artisanal métiers with low economic profitability but high level of environmental and social sustainability. On the other hand, although analyses in other Spanish artisanal fisheries have shown a low level of discards (averaging just 4.13% of the total weight according to Forcada et al. [10] , and some experiments specifically carried out with Asturian artisanal métiers as the Mullus gillnet [52] have shown that only 7.9% of the total catch weight is discarded, an increasing attention must be paid to artisanal net métiers selectivity, given that they become even more important among the Asturian artisanal fleet, so evaluation (and regulation) of “good practices” for an environmentally sustainable fishing activity could be recommendable.

It is hoped the present identification and characterization of Asturian artisanal métiers helps future management measures for artisanal fisheries. Nevertheless, exploring the pattern of métier rotation throughout longer time series would provide useful insights of the artisanal fishing activity and changes on fishing effort distribution [10] [48] . As well, improving knowledge on variable fishing tactics over the years, reasons and motivations explaining switching between métiers are considered key issues that deserve further research for the forecast and sustainable management of fishing effects on exploited stocks. In addition to this, it is necessary to highlight that future research will have to take into consideration total catches (including discards and unsold captures) in order to properly assess the fishing effort exerted by artisanal vessels at a regional scale. Moreover, it will be desirable to have available other kind of artisanal fisheries data in the near future, provided by logbooks or vessels monitoring systems (VMS) [16] that considerably increase accuracy and information about métiers effort in this region.

A métier-based approach is very useful to understand the spatio-temporal patterns of fishing effort allocation and catches, as well as to design and implement specific management measures based upon a good knowledge on the characteristics and problems of each métier. Although the problem of identifying métiers in the South- European area has been traditionally addressed in fisheries research, limitations on fishing data concerning vessels under 12 metres have excluded most of artisanal boats from many relevant analyses. Thus, when accurate, reliable and quantitative information on spatial and temporal fishing patterns for most of artisanal vessels is not available, many studies have applied alternative approaches as onboard samples or surveying methods to identify and characterize métiers, even though these sources mainly provide qualitative information and also have reliability problems. In this context, there is no precedent in exploring the potential of other sources of information to identify and characterize métiers in poor-data artisanal fisheries.

This study was aimed at achieving a detailed and updated characterization of the main technical, biological and economic issues concerning the métiers currently used by the artisanal fishing fleet of Asturias, an Atlantic region located in Northwest Spain. To reach this goal, a novel approach using administrative data on fishing licenses combined with daily sales registers and information collected through a surveying process has been applied. A value added of this approach, in poor-data contexts, is that it allows reaching highly disaggregated and detailed artisanal metier identification and classification, which comprehend all the richness and diversity of métiers practiced by these types of boats, and provides higher resolution than other classification frameworks. In the present case study, where the regional fleet is mainly artisanal and involved over 230 vessels in 2009 (70% of the whole fleet), applying this method required a detailed analysis of the regional administrative register of artisanal fishing licences used per day and vessel in the region during a whole year (more than 14000 fishing operations).

As a result, 21 métiers were identified, 16 of which were fully active in 2009. Findings have outlined the strong coastal, close-to-port character of the Asturian artisanal fleet, as well as a high annual rotation of fishing métiers and gears types that confirms its polyvalence and versatility. Nonetheless, certain métiers are used extensively by the artisanal fleet, producing the major part of landings and revenues of these vessels: Lophius trammel net and Merluccius longline generate the 28.6% of landings and 43.1% of the total income generated by artisanal fisheries in 2009. In terms of spatial distribution, the identified métiers are located in several fishing ports covering broad geographical areas: 12 of the active métiers (75%) are present in 7 or more different fishing ports. Only a few traditional métiers carried out in shallow waters close to the shore (as Anguilla pot and glass eel fishing) are restricted to some specific locations: these métiers (mostly traps) also present the highest seasonal pattern (whereas most of the net and longline gears are used during larger periods of the year). From an economic point of view, results by vessel typology have confirmed the existence of significant differences in terms of technical characteristics and workforce demands among vessels depending on the performed métiers. Additionally, although the average landings weight was 99.19 kg and the average income was €396.65 per sale bill in 2009, Asturian artisanal métiers showed significant differences: the rod-hook targeting Scomber scombrus is the métier that generates the highest weight (1468 kg) and income (€886), being also important the Merluccius longline and gillnet métier (an average income of €434 and €425 respectively per fishing day) and the Lophius trammel net métier (€423). Another interesting output of this research is that artisanal fishing patterns within Asturian fleet have changed significantly in the last years, and some of the identified métiers are nowadays in disuse or barely employed: as nets register lower exploitation costs than hooks, lines and traps, many vessels have recently invested in trammel net gears (Lophius trammel net).

The discussion of some findings in this article lead to other questions linked to the design of specific sustainable management measures in the context of South-European artisanal fisheries. Firstly, when highly heterogeneous artisanal vessels represent a relevant part of the whole fleets, management and planning measures should be designed and implemented taking into account métiers heterogeneity and the high level of internal complexity of artisanal fleets, avoiding grouping these vessels together within the same “uniform” category (i.e. named “Artes menores” in Spain, “Only passive gears” at a European scale, etc.). Secondly, it was confirmed that some vessels are limited to exploit relatively seasonal fisheries surrounding the home ports, especially when adverse weather may put boats at risk; given their constraints to redistribute their fishing effort, certain artisanal métiers (as glass eel fishing) and other fishing activities (as goose barnacle recollection, Pollicipes pollicipes), play in these periods a fundamental role as alternative/subsidiary fishing activities, when it is difficult and unprofitable to carry out another métiers. They become strategic at a local scale, as they provide income stability along the year to many artisanal fishermen. Finally, as part of the artisanal fleet is concentrating its activity on trammel net gears, a métier-diversity reduction is happening in parallel to a progressive cease of certain métiers; this changes suggest new sustainable management challenges: it should be evaluated the social and environmental role of artisanal métiers with low economic profitability in order to support them throughout the current fishing policy, whereas artisanal net métiers should be increasingly monitored in order to preserve the environmental sustainability of artisanal coastal fisheries.

This study was carried out within the PRESPO Project and co-funded by the European Regional Development Fund (ERDF) and the General Directorate of Maritime Fisheries of Asturias (Regional Ministry). Additionally, authors would like to thank Fishermen Guilds for their active collaboration and participation. Finally, we would like to thank reviewers for their detailed comments and insightful suggestions for the manuscript.

Javier González-Álvarez,Laura García-de-la-Fuente,Lucía García-Flórez,Mª del Pino Fernández-Rueda,Jorge Luis Alcázar-Álvarez, (2016) Identification and Characterization of M&eacute;tiers in Multi-Species Artisanal Fisheries. A Case Study in Northwest Spain. Natural Resources,07,295-314. doi: 10.4236/nr.2016.76026