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Technical developments and tactical adaptations of important EU fleets

Deliverables

Fishing effort was adjusted on the basis of the model developed in previous analyses (Production of a fishing effort model accounting for technological developments and fleets adaptation - Result 32229 of the e-tip), and related to fishing mortality. Adjusting fishing effort, by means of, - The metier effect and, - The indices of tactics and strategies and, - Selected vessel and gear technologies, generally lead to a substantial gain in the precision of the relationship between fishing mortality and fishing effort.
Fisheries data often contain catch and effort information from different kinds of vessels, operating in different kinds of fleets and fisheries. However, in some cases it would be usefull to make a distinction between vessels that operate in different fleets, or between fishing trips carried out in different fisheries. A fleet is a physical group of vessels sharing similar characteristics in terms of technical features. It is relatively easy to assign a vessel to a fleet. It is more complicated to assign a fishing trip to a fishery, because a fishery is defined as: group of vessel voyages targeting the same (assemblage of) species and/or stocks, using similar gear, during the same period of the year and within the same area. Within the TECTAC framework a methodology for fisheries definition was developed. This methodology consists of three steps to define the fisheries within a fleet: - A multivariate analysis of the catch or landings data by trip, in terms of species composition by value, which defines the landing profile; - An analysis to investigate the relationships between the features of the voyages in terms of gear type, mesh size, fishing area, time period, vessel characteristics, etc., and their outcome in terms of catch or landings profile; and - A definition of fisheries that are considered sensible both from the results of the second step, and in relation to the ad hoc knowledge on the fisheries.
Face to face interviews have been undertaken to identify the main changes in gear and vessel technology, which have improved the fishing efficiency of a number of French, Danish, English and Spanish fleets, over the past decades. Changes to deck equipment are regularly made to increase efficiency and there is a tendency in each fishery to reduce the number of crew, as this reduces costs. The replacement of a vessel�s engine was linked to the engine breaking down or to reduce the risk of breakdown. The vast majority of vessels surveyed have installed state of the art onboard electronic equipment after it has become available. The rate of uptake varies from 4 years until all the vessels have the technology to 9 years with an average of about 6 years. This equipment results in improved species location together with improved communications between vessels. Other specific features are the gradual appearance of twin trawls (Danish and French trawlers) and of trammel nets (French gill-netters), and the increased polyvalence of Basque bottom-trawlers.
This result is a extension of the identification of fisheries (or metiers) made during WP1 (cf result 32226). The trends observed in metiers allocation over more than ten years were analysed in two case studies, the whole Danish fleet and the French offshore fleet in the North Atlantic. In both cases, trips were first allocated to a metier using multivariate analyses (PCA+HAC+MCA). Then the vessels were subsequently yearly aggregated into vessel groups (referred to as fishing strategies in the French case), based on their activity in the different metiers during a calendar year, also using PCA and HAC methods. The temporal trends of both metiers and vessel groups were thus described in terms of level of effort and number of vessels. Main results showed that all fleets were specialised in terms of gear used, but flexible in terms of fishing grounds and target species. Major strategically changes were observed during the last decade, and they could be qualitatively related to changes in stock abundance, regulations or market price.
Analysis of the observed trends in the dynamics of production allows a preliminary assessment of the impacts on fleet activity and fleet performance of different categories of management policies (e.g. capacity reduction programmes, TAC) and economics (e.g. fish prices, operating costs). Policies which favoured the renewal of certain fleets have had an impact on the global economic performance of those fleets, and on their capacity to absorb external shocks such as the market crisis, or the increase in fuel prices, relative to older fleets. Even if buyback schemes were not specifically targeted at smaller vessels, the fact that larger vessels performed better from an economic perspective entails reduced incentives to decommission vessels for their owners. Hence the limited impacts of decommissioning policies on these vessels, observed in the study of South-Brittany trawler fleets. Most of the fleets investigated have reacted to reductions in TACs by shifts in target species and/or increasing their productivity in relation to the species subject to low quota. Depending on the fleets, these strategies have partially or completely offset the quota reduction in terms of revenue. In addition, price increases for low quota species have sometimes contributed to level up revenues. In other case however, reductions in total and average landings of certain species have been concomitant with reductions in prices. This is an indication of the influence of changes in markets, driving the prices of landings, rather than these landings impacting prices. The fact that in some cases, an increase in total and average production of certain species is concomitant with an increase in the price of these species, also indicates that fleets change their effort allocation strategies in response to changes in the relative value of the different species they can catch. In addition to management regulations, changes in the economic context in which fleets operate also have affected the fleets. As stressed above, changes in markets for fish have in some cases had a strong impact on the evolution of fleet revenue. Other changes observed in the fleets where cost data was available relate to the increase in the price of key inputs, particularly fuel price, in recent years. In some cases, the analysis however shows that the impact of higher fuel prices has been at least partly compensated by adaptations in the cost structure of fishing firms (e.g. decline in crew costs).
Deliverable 12b is the report detailing the work undertaken towards the development of state-of-the-art empirical behaviour models. Firstly, a review of the modelling of fishermen’s choice is given, categorising behaviour under effort allocation (e.g. location choice and optimal foraging), entry-exit, compliance and discarding. The method of random utility (or discrete choice) modelling is one of the important surrounding the empirical modelling of behaviour. This is then applied to case studies looking at both short-term (choices of gear, species and areas) and long-term behaviour (entry-stay-exit decisions). Case studies for the Basque trawl fleet, the English beam trawl fleet operating in the North Sea, the Danish North Sea gillnet fleet, the South-Brittany trawl fleet and the Galician fleet in the Celtic Sea are developed. In addition, to random utility models, other empirical modelling approaches were investigated that considered: an agent-based approach for modelling fleet response, an impact analysis of fuel prices and an analysis of the characteristics of fishers and their behaviour strategies following area closures. In addition to these specific studies, a general introduction to the economic behaviour of producers is also provided. All of the case studies developed for this component of the project have been presented at conference and appear in proceedings, and the majority have been submitted for publication in peer-reviewed journals. The results and experiences gained from this component of the project have been used in the development of simulation models. Their use is also likely to extend beyond this project into other EU and nationally funded studies.
A SAS script was written for evaluation of the quality of auxiliary data (TACENQ and TACSAT). The script is applicable to each national data table and generates graphs of data availability (number of ships, trips) and of parameter ranges (haul duration, time of setting the net, fishing depth etc.). Also maps of catch (by species) and effort distribution are generated. These graphs and maps can be used to make a quick inventory of the contents of the data table and of possible mistakes in the data. Another SAS script was written to compare the auxiliary data (TACENQ and TACSAT) with the existing data (EFLALO). This script produces graphs that can be used to get an idea of the overlap in both data tables (catch and effort by ship & trip, catch and effort by ICES rectangle etc.). Also maps of effort distribution in both data tables can be compared.
Deliverable D6b is the report on the external factors (changes in management, market shifts and fish stock density) that influence fishermen and their decision-making processes (based on the database (D6a). The report is based on the surveys of five case studies, all of which are demersal fisheries. The case studies were as follows: French Bottom-trawlers fishing in the Bay of Biscay, Basque trawlers fishing in ICES sub-area VIII, Galician trawlers and longliners targeting hake in the Celtic Sea, English beam trawlers fishing in the English Channel and Celtic Sea and North Sea, and the Danish Demersal fleets (trawlers, seines and gillnetters) fishing in the North Sea and surrounds. In summary, fishermen take up their profession based on family influence, inheritance and in order to earn a living. Changing a fishing vessel or not changing a vessel is mainly based on economic factors such as opportunity costs. Changes to deck equipment are regularly made to increase efficiency and there is a tendency in each fishery to reduce the number of crew, as this reduces costs. The replacement of a vessel�s engine was linked to the engine breaking down or to reduce the risk of breakdown. The vast majority of vessels surveyed have installed state of the art onboard electronic equipment after it has become available. The rate of uptake varies from 4 years until all the vessels have the technology to 9 years with an average of about 6 years. This equipment results in improved species location together with improved communications between vessels. Modifications made to gear primarily appear to be to increase efficiency and in some cases may be in response to changing fishing opportunities. External factors (changes in management regulations, market shifts and fish stock density) constrain fishing operations and in order remain competitive fishermen require changes in technology to achieve greater efficiency. Output-based fisheries management strategies do not necessarily take into account these changes in efficiency leading to situations where effective fishing effort exceeds the resources that can be harvested. The key features of these results were closely linked to the research conducted in the same project on discrete choice modelling of fisher behaviour which essentially models key factors of behaviour identified in this deliverable.
One important challenge of the TECTAC project was to merge information from existing surveillance programmes (e.g. log-books) with information that lye outside the traditional recorded measures of fishing effort and yield. Auxiliary data sources have included accountancy records, regulatory orders, and new information from electronic log-books, in-depth interviews and harbour enquiries. A common structure was agreed by the consortium to compile both routinely recorded and newly acquired data into standard tables. The following tables were generated: - EFLALO: Effort and landings, based on combined log-books and sales slips; - LASORT: Landings by market sorting categories, based on sales slips; - TECVESS: Technological developments of vessel, based on both harbour and on-board enquiries; - TECGEAR: Technological developments of gears, based on both harbour and on-board enquiries; - TACENQ: Fishing tactics: haul-by-haul data; - TACSAT: Fishing activity, based on satellite monitoring; - ECOENQ1: Costs and earnings, by year and by vessel; - ECOENQ2: Costs and earnings, by year, vessel and fishing trip; - MANENQ1: Vessel- and gear- related management measures; - MANENQ2: Minimum landing sizes by species; - MANENQ3: TAC by species The format of EFLALO, TECVESS, TECGEAR, TACENQ, TACSAT, MANENQ1, MANENQ2 and MANENQ3 was common to the consortium. The format of ECOENQ1 and ECOENQ2 was country-specific. All data, both routinely recorded and newly acquired, were computerized into standard tables by each country. Given the specificity of economic data within national institutes, it was decided to keep ECOENQ1 and ECOENQ2 (costs and earnings) country-specific. The consortium also concluded that only little use would be made of the LASORT (landings by market sorting categories), and no further consideration was given to this database in the course of the project. This database structure was used to a large extent during the TECTAC project to compile data and provide directly inputs to the analyses. It is also available, with minor adjustments, for future projects pertaining fleet dynamics (e.g. the CAFE project which starts in 2006). In addition, another database structure was generated to compile aggregated data. Two tables were aggregated, i.e. EFLALO and TACENQ, and the data compiled, and these have been submitted on a CD-ROM to the Commission.
The bioeconomic models developed were used for the simulation of the international North Sea flatfish fishery (TEMAS 2.0) and the Bay of Biscay hake-nephrops (ISISFish 2.0) respectively. Models settings used data from the EFLALO database, and effort allocation modules were parameterised using the latest results from previous workpackages. Simulations were run to compare alternative modelling hypotheses and alternative management scenarios
Bioeconomic simulation models were developed to quantify and compare impacts of management measures on fleet and population dynamics. Two existing generic models (TEMAS 1.0 in DIFRES and ISISFish 1.0 in IFREMER) were used and expanded, to integrate the latest results on fleets effort allocation and reactions to management obtained during the project. The TEMAS 2.0 model includes an operating model simulating stocks and fleets dynamics with RUM-based tactical effort allocation, and a management model dynamically simulating current assessment and management procedures. The ISIS 2.0 model includes a spatially explicit bioeconomic simulation of stocks and fleets dynamics with a gravity model-based tactical effort allocation.
Three separate investigations were carried out to analyse the elements of fleet dynamics, the first two focusing on fishing tactics and strategies, and the latter on technological development. The scope of the first investigation is to quantify, for a wide selection of European fisheries, fishing tactics and strategies, and to evaluate the benefits of adjusting the definition of fishing effort using these elements. Fishing tactics and strategies were identified by metiers choices and a series of indices. These indices have been derived to reflect shifts in tactics (within a fishing trip) and in strategies (within a year). The Shannon-Wiener spatial diversity indices of tactics (FT_SW) and strategies (YE_SW) had the greatest impact on catch rates. In particular, FT_SW was always negatively correlated to catch rates. One may anticipate that during a fishing trip, vessels with high FT_SW have been searching fish aggregations for a long time, while vessels with low FT_SW have been more efficient in finding these aggregations. The linkage between YE_SW and catch rates was of a more complex nature. The second study has investigated some properties of fishermen�s foraging, using Levy flights theory. The case studies examined were a selection of North Sea Dutch and French vessels, for which catch and effort data were collected on a haul-by-haul basis. Foraging behaviour could reasonably be represented by a Levy flight process for both fleets. The properties of fishers� foraging were further investigated for the Dutch fleet using time series analysis. Efficient foraging led to high value per unit effort, while the knowledge of fishing grounds with high stock density is shown to increase foraging efficiency in the short-term future. Efficient foraging resulted in high levels of fishing effort 4 or 7 months later. By contrast, High levels of fishing effort may induce local depletion on fish stocks, and subsequently adversely affect foraging efficiency. The linkage between foraging and fish prices was complex. It could be explained by fish prices only partially reflecting the economic drivers of fishers� behaviour. Regarding the third investigation, face-to-face interviews have been undertaken to identify the main changes in gear and vessel technology, which have improved the fishing efficiency of a number of French, Danish and Basque fleets, over the past decades. Important features are the gradual appearance of twin trawls (Danish and French trawlers) and of trammel nets (French gill-netters), and the increased polyvalence of Basque bottom-trawlers. The results suggest that fishing effort descriptors which are not traditionally measured (gear type, ground rope type, length of net used per day, headline length, crew size, number of winch or net drums) may have a substantial impact on catch rates.
Fisheries management comprises different types of regulatory measures that may influence fishing firms and fleets behaviour. They may ration the production possibilities of vessels or/and give fishermen economic incentives to change their behaviour. However, fisheries management tools are heterogeneous in nature and their aims could be different. A typology of management measures has been operated for a selection of E.U. fleets. Based on this typology, a review of the regulations applicable to the different fleets has been carried out. One of the main conclusions of the study is that all the fleets operate in a context of individual access allocation, either through the control variable of effort or catches or both.
Deliverable 7 is included in the report on external factors that influence fishermen and their decision-making processes and principally focuse on the factors that affect their decision-making process when changing fishing tactics and strategies. In-depth interviews were conducted in the case study of Danish Demersal fisheries which covered three different fisheries: the demersal fisheries in the North Sea, the Nephrops fisheries in Kattegat, Skagerrak and the North Sea and the cod fisheries in the Baltic Sea. For the other case studies (Basque trawlers, Galician trawlers and longliners, English beam trawl fleets) questions on tactics where also included as an addendum to the quantitative survey that formed the basis of Deliverable 6. For the other case studies, the questions relating to fishing tactics covered three main topics such as: questions about fishing location and how skippers decide where to fish; questions on gear used and species targeted and questions on fishing activity and the routine of fishing trips. For the in-depth interviews on Danish Demersal fisheries a factor analysis is conducted to show the differences in the fishermen�s tactical decisions and a typology is developed for the fishermen�s investment strategies. In total, 789 questionnaires were issued to skipper/owners, 271 or 34% of them responded. Seventeen in-depth interviews were conducted. The results of the studies indicate that tactical decisions i.e. broadly when, where and how to fish on a trip basis, are influenced by a number of factors including regulations. Fishermen are hunters by nature and will adapt their tactical behaviour to imposed regulations by taking actions that will minimise the economic losses incurred by very restrictive measures. Fishing is about exploitation of nature and thus an immense knowledge of how to do so most efficiently has been built up by the fishermen. Fishermen thus follow their own instincts based on their knowledge. In the case of the in-depth study on Danish demersal fleets, information and/or experience from the last fishing trip and the present fish prices were found to have the greatest influence on fishermen�s tactical behaviour, followed by their experience of what they did at the same time the previous year. Winds and the currents also have an influence but are less important. Fisheries regulation was only rated either 4th or 5th as the determinant of fishing practice in the fisheries. Thus, it appears that regulation is not a primary consideration unless a particular regulation prevents access to a fishing ground or species in time and/or space. However, the results still emphasizes the importance of elaborating and articulating regulations that to a much larger degree take into account the behaviour of fishermen and this led Christensen and Raakjær Nielsen (2004) to conclude that there is scope for management to become more flexible and, to a larger degree, accommodate the specific challenges for the different fisheries. The key features of these results were closely linked to the research conducted in the same project on discrete choice modelling of fisher behaviour which essentially models key factors of behaviour identified in this deliverable.

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