– The Central Mediterranean provides important neritic habitats for loggerhead turtles (Caretta c... more – The Central Mediterranean provides important neritic habitats for loggerhead turtles (Caretta caretta), but Mediterranean bottom trawlers catch an estimated 30 000 turtles a year, with 25 % mortality. Mortality by trawling is mainly due to enforced apnoea during towing activity. In order to reduce the submergence time and consequent turtle mortality, a specific technical modification was developed in the early 1980s: the Turtle Excluder Device (TED). In this paper, we field-tested a typical Supershooter TED and three new types of low-cost TED, built with different designs and materials, incorporating aspects of US and Australian TEDs, as well as design features to improve handling and catch rates. The performance of the TEDs was investigated under commercial fishing conditions in diverse trawling grounds in the Adriatic Sea (Mediterranean). All TEDs were easy to operate and did not require changes to normal fishing operations. Due to lack of entry of turtles it was not possible to...
Baltic Sea Benthic ecosystem impacts from demersal fishery in the western Baltic is assumed to co... more Baltic Sea Benthic ecosystem impacts from demersal fishery in the western Baltic is assumed to come mainly from Nephrops trawling in the central and southern Kattegat, mussel dredging in the Belt Sea, and mixed cod trawling in the western Baltic Sea.These fisheries both impact the seabed, as well as produce substantial amounts of discards. The western Baltic Sea offer a unique opportunity to analyse the benthic effects of fishingthanks to the closure of Oresund to towed gears since the 1920s, and the introduction of the Kattegat MPA in2009 (including cod closure) and the western Baltic Sea Natura-2000 areas. Furthermore an extensive benthic nationalmonitoring and data collection effort has taken place in the area over a number of years, which can be usedto investigate spatial and temporal differences in the development of benthic communities in (chronically) towed and non-towed areas. To evaluate benthic impacts of towed gears in the Baltic Sea a number of gear technological innovat...
Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee... more Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report deals with the revision of the EU-MAP and Work Plan template. The Expert Group report was reviewed during the 2019 STECF November plenary meeting during the 2019 STECF November plenary meeting.
Computational modeling is a valuable complementary tool to assess behavior of bottom trawl fishin... more Computational modeling is a valuable complementary tool to assess behavior of bottom trawl fishing gears. A simplified model of the gear that mainly affects to the net is proposed. The model is constrained to steady towing conditions, flat seabed and gear symmetry. Simulations proportionate a number of relevant outcomes like distribution of tensions at the warp, balance of forces at the otterboards or spread under different haul conditions such as depth or towing speed. In this paper we mainly focuss on the description and implementation of the model. Nevertheless, some preliminar comparison with experimental data is also shown.
In this deliverable we investigated the drivers of investment in fisheries and how those can be a... more In this deliverable we investigated the drivers of investment in fisheries and how those can be activated to stimulate investment in alternative technologies to protect the benthos. To capture a wider range of factors than quantitative factors only we modified the work plan and included interviews with fishing industries in all regions. As a result we identified a wide range of reasons why fishers have (or have not) invested in alternative gears. As expected, the profitability of alternative technology is an important factor to invest but we also found many others. Those drivers were classified as economic, technical, regulatory, social, governance and environmental drivers. As advice to managers we also identified where and how interventions could improve uptake of technology.
Models to predict codend size selectivity for four major commercial species-European hake (Merluc... more Models to predict codend size selectivity for four major commercial species-European hake (Merluccius merluccius), Norway lobster (Nephrops norvegicus), deep-water rose shrimp (Parapenaeus longirostris), and Atlantic horse mackerel (Trachurus trachurus)-in Mediterranean bottom trawl fisheries were established based on data collected during fishing trials using the two legal codends: a 40 mm square-mesh codend and a 50 mm diamond-mesh codend. The models were applied to predict the extent to which size selection depend on codend type, also accounting for the potential effect of codend catch size and fishing season. The size selectivity of the two codends was evaluated and compared in identical simulated controlled conditions. Mesh type significantly affected the size selection of Norway lobster alone, with a slightly better performance of the 40 mm square-mesh codend. A high risk of retention of undersized individuals was predicted for both codends for all species except Norway lobster.
Two pelagic otterboards, previously tested in a wind tunnel, have been tested in a flume tank pri... more Two pelagic otterboards, previously tested in a wind tunnel, have been tested in a flume tank prior to their analysis in real working conditions in sea trials. This intermediate step aims at providing guidance for sea trial planning and a basis for otter board performance analysis from real campaign data. The doors were rigged in working-like conditions in the flume tank, with onboardmounted attitude sensors to provide at the same time a noisy environment as expected in sea trials and accurate measurement of all quantities relevant to precise determination of hydrodynamic angles and forces. The trends found in flume tank experiments closely match wind tunnel results, although systematic offset has been observed that can be ascribed to deviations between nominal and real water velocity, due to inhomogeneous veloctiy distribution in the cross-section.
Chondrichthyes - Multidisciplinary Approach, Dec 20, 2017
This chapter reviews the current state of knowledge about global chondrichthyes bycatch, includin... more This chapter reviews the current state of knowledge about global chondrichthyes bycatch, including how the combination of biological characteristics of these species and the impact of different fishing methods reflect their vulnerability to bycatch. Specifically, it summarizes the present status of elasmobranchs and chimaeras bycatch worldwide. Following this, it illustrates the main ecological consequences behind such incidental captures. Hence, it provides a description of how chondrichthyes bycatch occurs across broad fishing gear categories. Moreover, it outlines potential mitigation options available to reduce bycatch. As such, the main technical measures tested and applied in different fishing practices are listed. In addition, an overview about which are the current management measures implemented at international level to ensure long-term conservation of cartilaginous fish is reported. Then, two case studies summarize how chondrichthyes bycatch occurred in some of the most exploited fishing areas. Finally, the chapter ends with relevant considerations about potential for new research needed to monitor and reduce chondrichthyes bycatch.
Models to predict codend size selectivity for four major commercial species—European hake (Merluc... more Models to predict codend size selectivity for four major commercial species—European hake (Merluccius merluccius), Norway lobster (Nephrops norvegicus), deep-water rose shrimp (Parapenaeus longirostris), and Atlantic horse mackerel (Trachurus trachurus)–in Mediterranean bottom trawl fisheries were established based on data collected during fishing trials using the two legal codends: a 40 mm square-mesh codend and a 50 mm diamond-mesh codend. The models were applied to predict the extent to which size selection depend on codend type, also accounting for the potential effect of codend catch size and fishing season. The size selectivity of the two codends was evaluated and compared in identical simulated controlled conditions. Mesh type significantly affected the size selection of Norway lobster alone, with a slightly better performance of the 40 mm square-mesh codend. A high risk of retention of undersized individuals was predicted for both codends for all species except Norway lobster.
We present a framework for Results Based Management (RBM) of commercial fisheries. The core idea ... more We present a framework for Results Based Management (RBM) of commercial fisheries. The core idea of RBM is to reduce micro-management by delegating management responsibility to resource users. The RBM framework represents an industrial organization approach to comanagement and comprises three defining processes, conducted by three independent "agents": 1) an "authority" defines specific and measurable and achievable objectives (outcome targets, OTs) for the utilization of fisheries resources, 2) resource user organizations (termed "operators") take responsibility for achieving these OTs and provide documentation that 3) allows independent "auditors" to evaluate the achievement of OTs. Using incentive mechanisms, notably deregulation, RBM grants operators the flexibility to develop and implement innovative and cost-effective ways to achieve OTs. The feasibility of implementing RBM in five European fisheries was investigated in cooperation with relevant stakeholders through artificial planning processes and computer simulations. The operators involved were enthusiastic, and new management plans were drafted based on the framework. These included socioeconomic OTs in addition to traditional stock objectives, encompassing an ecosystem approach. Several issues are in need of further research in order to consolidate the approach and prepare the ground for practical implementation, including: the specification of the legal and regulatory framework required to underpin RBM, details of transitional arrangements when shifting towards RBM (including cost-sharing) and the development of necessary organizational capacity for operators. Initially, we therefore envisage the framework being applied to high value single species fisheries, with a limited number of participants, which are adequately represented by a competent organization.
Abstract Fisheries involve an intensive use of European maritime regions according to the Common ... more Abstract Fisheries involve an intensive use of European maritime regions according to the Common Fisheries Policy (CFP). The recent CFP reform has adopted an ecosystem-based approach to fisheries management that is characterised by enhanced regionalisation and multi-annual management plans. It aims to avoid the adverse environmental impacts of fishing activities, which are to be mitigated as far as possible, while the wasteful practice of discarding unwanted catches is to be phased out by 2019, at least for species with minimum landing size. The paper investigates the ability of selected measures, envisaged by the CFP reform through the European Maritime and Fisheries Fund (EMFF), to sustain and attain the objectives of the European Marine Strategy Framework Directive, which aims at achieving Good Environmental Status (GES) in marine waters according to an ecosystem-based approach. The analysis uses an expert judgment-based approach and a specially devised questionnaire, where fisheries science and management experts were asked to assess the impact and interaction of selected EMFF measures on GES achievement as defined for the Italian seas. Their responses are discussed and compared with information coming from an extensive literature review. The results of the analysis highlight a general agreement between EMFF actions and GES objectives but also identify some potential conflicts.
Fishing pressure is often expressed in terms of a vessels physical attributes, like tonnage and e... more Fishing pressure is often expressed in terms of a vessels physical attributes, like tonnage and engine power, while a common definition of fishing capacity identifies vessel size as a convenient proxy for the size of the gear used. Nevertheless, these definitions remain arguable, and the refinement of these fishing descriptors is increasingly being considered. A stronger understanding of the relationship between the standard measures of effort and capacity and fishing mortality remains a primary objective, followed by the need to overcome a traditional approach that simply describes effort, capacity and mortality as linearly related, conferring a greater fishing power to larger vessels. In this perspective, the analysis of trawlers' technical features in relation to the size and power of the vessel might constitute an essential step. This study specifically investigated a collection of trawling gears' technical specifications collected by CNR-IRBIM, Ancona. The dataset used includes records from several Mediterranean fisheries, and involves three trawling techniques, including single trawling, twin trawling and pair trawling, and diverse trawling gear categories, comprising demersal/bottom 2-panel trawls (OTB2), demersal/bottom 4-panel trawls (OTB4), pelagic 4-panel trawls (PTM4), semi-pelagic 2-panel trawls (OTM2), semi-pelagic 4-panel trawls (OTM4), and a Mediterranean bottom beam trawl (TBB). We analyzed and described the relationships between vessels' technical features (LOA, towing force, and engine power), some among the main trawl-metrics (headline length, footrope length, trawl length, square width; fishing circle) and the otterboard's technical features (height, width, and projected area) in an attempt to enhance fishing capacity definition through the inclusion of the fishing gear deployed. Self-organizing maps (SOM) were used to explore the empirical relationships among different parts of the fishing trawl gears, as well as between some of these parts, the otterboard size and the engine power of the vessel.
Abstract Fishing is an energy-intensive economic activity. Research in several fields is conducte... more Abstract Fishing is an energy-intensive economic activity. Research in several fields is conducted to improve the energy and environmental profile of fishing vessels. As regards the technical measures, the assessment of benefits is often hampered by boundary conditions that are difficult to quantify and side effects that are difficult to unravel. This study examined the impact of a fluoropolymer-based fouling release paint on the fuel consumption rate of a Mediterranean bottom trawler. The analysis of a series of sea trial campaigns allowed for a quantitative and qualitative comparison of fuel consumption rate during the regular fishing activities. Comparing the fuel consumption rate before and after the application of the fluoropolymer-based foul-release coating, a reduction in fuel consumption rate was observed and quantified. Other advantages are discussed in this paper regarding the reduction of GHG emission, and the more environmental-friendly approach using biocide-free and non-banned products.
The European Food and Nutrition Action Plan 2015–2020 encourages Member States to promote local a... more The European Food and Nutrition Action Plan 2015–2020 encourages Member States to promote local affordable and healthy dietary initiatives to support a sustainable food system, particularly in schools and public institutions where advertising on eating behaviour and food preferences is needed. In Italy, the promotion of healthy and sustainable diets, including the consumption of oily fish, is at an early stage. Based on the success of a unique Italian educational campaign in school lunch programmes, the aim of the present study was to compare the nutritional composition of locally caught anchovy and of imported frozen fillets of farmed Vietnamese pangasius, to observe the potential implications of this dietary substitution. Anchovy showed a significantly higher fatty acid and protein content than pangasius, and contained five times more lipids, mainly n-3 and n-6 polyunsaturated fatty acids. As previous studies confirmed, a diet providing large amounts of these fats is therefore rec...
Despite the fact that Mediterranean loggerhead turtles are listed as "Least Concern" by the Inter... more Despite the fact that Mediterranean loggerhead turtles are listed as "Least Concern" by the International Union for the Conservation of Nature (IUCN), they are among the most threatened marine megafauna worldwide, because of fishery-related incidental captures. The northern central Adriatic Sea is one of the most overfished basins of the Mediterranean Sea and it supports a very valuable marine biodiversity, including sea turtles. This study assesses the spatial and seasonal impact of the northern central Adriatic midwater pair trawl fishery on loggerhead turtle (Caretta caretta) by examining incidental catches recorded between 2006 and 2018 and environmental variables. The model predicted seasonal variation of loggerhead distribution. According to previous studies, data analysis indicates that most bycatch events of loggerhead turtle occurred in the northern Adriatic Sea. The present data confirm that the northern Adriatic may be an important foraging area for loggerhead turtle. They also highlight the urgent need for a better understanding of the interactions between sea turtles and fisheries to develop and apply suitable, ad hoc management measures in critical habitats.
The Mediterranean Sea is a hotspot of biodiversity, but the high fishing pressure results in high... more The Mediterranean Sea is a hotspot of biodiversity, but the high fishing pressure results in high bycatch rates of protected (sea turtles and cetaceans) and top predator species (sharks). The reduction of bycatch is challenging for fishery scientists, as conservation of these species has become a priority. Among the animals threatened by fishing activities, the loggerhead (Caretta caretta) represents a charismatic species considered as “vulnerable” at the global scale by IUCN. In the Mediterranean Sea, trawl nets show the highest probabilities of bycatch of protected species, with high rates of mortality. A new flexible Turtle Excluder Device (TED) has been tested for the first time on a commercial scale in the Mediterranean Sea to assess its effectiveness in reducing bycatch. The results did not show any significant (α = 0.05) loss in terms of commercial weight, but a significant reduction of debris in the codend of the nets mounting the TED respect to traditional nets. The catch c...
Mediterranean trawl fisheries are characterized by a critical combination of high fishing effort ... more Mediterranean trawl fisheries are characterized by a critical combination of high fishing effort and low size at first capture for most commercial species. In this study we tested the use of sorting grids installed on bottom trawl nets to minimize the catch of undersized deep-water rose shrimp (Parapenaeus longirostris, DPS) and European hake (Merluccius merluccius, HKE). The catch of a traditional trawl net was compared with that obtained with the same net equipped with ad hoc designed juveniles and trash excluder devices (JTEDs) during an experimental survey. Three different JTEDs were tested: the first (G1-SM40) was built with a net of 40-mm square mesh; the second (G2-ST20) and third (G3-ST25) with vertical steel bars spaced 20 and 25 mm, respectively. The probability of retaining DPS and HKE by length class in trawl nets with and without JTED was analysed using generalized additive mixed models. With G1-SM40, the reduction of undersized individuals in the cod-end was about 60% ...
Gear selectivity and discards are important issues related to fisheries management but separately... more Gear selectivity and discards are important issues related to fisheries management but separately modelled. This work examines for the first time the overall size-selection pattern on the total amount of individuals of a species entering the trawl codend. An innovative approach was used based on modelling the escapement through the codend in the sea and the subsequently selection process by the fisher on the deck of the fishing vessel resulting into the discards and landings. Three different trawl codends and three species were investigated in the case study conducted. A dual sequential model accounting for both gear size-selectivity and the subsequent fisher-size-selectivity was applied, under the hypothesis that a fish entering the codend can follow a multinomial distribution with three probabilities, the escape, the discard and the landing probability, respectively. The model described the escape probability through the gear and the landing probability by the fisher as S-shaped c...
Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental c... more Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus), spiny dogfish (Squalus acanthias), common eagle ray (Myliobatis aquila), and pelagic stingray (Pteroplatytrygon violacea) by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures.
– The Central Mediterranean provides important neritic habitats for loggerhead turtles (Caretta c... more – The Central Mediterranean provides important neritic habitats for loggerhead turtles (Caretta caretta), but Mediterranean bottom trawlers catch an estimated 30 000 turtles a year, with 25 % mortality. Mortality by trawling is mainly due to enforced apnoea during towing activity. In order to reduce the submergence time and consequent turtle mortality, a specific technical modification was developed in the early 1980s: the Turtle Excluder Device (TED). In this paper, we field-tested a typical Supershooter TED and three new types of low-cost TED, built with different designs and materials, incorporating aspects of US and Australian TEDs, as well as design features to improve handling and catch rates. The performance of the TEDs was investigated under commercial fishing conditions in diverse trawling grounds in the Adriatic Sea (Mediterranean). All TEDs were easy to operate and did not require changes to normal fishing operations. Due to lack of entry of turtles it was not possible to...
Baltic Sea Benthic ecosystem impacts from demersal fishery in the western Baltic is assumed to co... more Baltic Sea Benthic ecosystem impacts from demersal fishery in the western Baltic is assumed to come mainly from Nephrops trawling in the central and southern Kattegat, mussel dredging in the Belt Sea, and mixed cod trawling in the western Baltic Sea.These fisheries both impact the seabed, as well as produce substantial amounts of discards. The western Baltic Sea offer a unique opportunity to analyse the benthic effects of fishingthanks to the closure of Oresund to towed gears since the 1920s, and the introduction of the Kattegat MPA in2009 (including cod closure) and the western Baltic Sea Natura-2000 areas. Furthermore an extensive benthic nationalmonitoring and data collection effort has taken place in the area over a number of years, which can be usedto investigate spatial and temporal differences in the development of benthic communities in (chronically) towed and non-towed areas. To evaluate benthic impacts of towed gears in the Baltic Sea a number of gear technological innovat...
Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee... more Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report deals with the revision of the EU-MAP and Work Plan template. The Expert Group report was reviewed during the 2019 STECF November plenary meeting during the 2019 STECF November plenary meeting.
Computational modeling is a valuable complementary tool to assess behavior of bottom trawl fishin... more Computational modeling is a valuable complementary tool to assess behavior of bottom trawl fishing gears. A simplified model of the gear that mainly affects to the net is proposed. The model is constrained to steady towing conditions, flat seabed and gear symmetry. Simulations proportionate a number of relevant outcomes like distribution of tensions at the warp, balance of forces at the otterboards or spread under different haul conditions such as depth or towing speed. In this paper we mainly focuss on the description and implementation of the model. Nevertheless, some preliminar comparison with experimental data is also shown.
In this deliverable we investigated the drivers of investment in fisheries and how those can be a... more In this deliverable we investigated the drivers of investment in fisheries and how those can be activated to stimulate investment in alternative technologies to protect the benthos. To capture a wider range of factors than quantitative factors only we modified the work plan and included interviews with fishing industries in all regions. As a result we identified a wide range of reasons why fishers have (or have not) invested in alternative gears. As expected, the profitability of alternative technology is an important factor to invest but we also found many others. Those drivers were classified as economic, technical, regulatory, social, governance and environmental drivers. As advice to managers we also identified where and how interventions could improve uptake of technology.
Models to predict codend size selectivity for four major commercial species-European hake (Merluc... more Models to predict codend size selectivity for four major commercial species-European hake (Merluccius merluccius), Norway lobster (Nephrops norvegicus), deep-water rose shrimp (Parapenaeus longirostris), and Atlantic horse mackerel (Trachurus trachurus)-in Mediterranean bottom trawl fisheries were established based on data collected during fishing trials using the two legal codends: a 40 mm square-mesh codend and a 50 mm diamond-mesh codend. The models were applied to predict the extent to which size selection depend on codend type, also accounting for the potential effect of codend catch size and fishing season. The size selectivity of the two codends was evaluated and compared in identical simulated controlled conditions. Mesh type significantly affected the size selection of Norway lobster alone, with a slightly better performance of the 40 mm square-mesh codend. A high risk of retention of undersized individuals was predicted for both codends for all species except Norway lobster.
Two pelagic otterboards, previously tested in a wind tunnel, have been tested in a flume tank pri... more Two pelagic otterboards, previously tested in a wind tunnel, have been tested in a flume tank prior to their analysis in real working conditions in sea trials. This intermediate step aims at providing guidance for sea trial planning and a basis for otter board performance analysis from real campaign data. The doors were rigged in working-like conditions in the flume tank, with onboardmounted attitude sensors to provide at the same time a noisy environment as expected in sea trials and accurate measurement of all quantities relevant to precise determination of hydrodynamic angles and forces. The trends found in flume tank experiments closely match wind tunnel results, although systematic offset has been observed that can be ascribed to deviations between nominal and real water velocity, due to inhomogeneous veloctiy distribution in the cross-section.
Chondrichthyes - Multidisciplinary Approach, Dec 20, 2017
This chapter reviews the current state of knowledge about global chondrichthyes bycatch, includin... more This chapter reviews the current state of knowledge about global chondrichthyes bycatch, including how the combination of biological characteristics of these species and the impact of different fishing methods reflect their vulnerability to bycatch. Specifically, it summarizes the present status of elasmobranchs and chimaeras bycatch worldwide. Following this, it illustrates the main ecological consequences behind such incidental captures. Hence, it provides a description of how chondrichthyes bycatch occurs across broad fishing gear categories. Moreover, it outlines potential mitigation options available to reduce bycatch. As such, the main technical measures tested and applied in different fishing practices are listed. In addition, an overview about which are the current management measures implemented at international level to ensure long-term conservation of cartilaginous fish is reported. Then, two case studies summarize how chondrichthyes bycatch occurred in some of the most exploited fishing areas. Finally, the chapter ends with relevant considerations about potential for new research needed to monitor and reduce chondrichthyes bycatch.
Models to predict codend size selectivity for four major commercial species—European hake (Merluc... more Models to predict codend size selectivity for four major commercial species—European hake (Merluccius merluccius), Norway lobster (Nephrops norvegicus), deep-water rose shrimp (Parapenaeus longirostris), and Atlantic horse mackerel (Trachurus trachurus)–in Mediterranean bottom trawl fisheries were established based on data collected during fishing trials using the two legal codends: a 40 mm square-mesh codend and a 50 mm diamond-mesh codend. The models were applied to predict the extent to which size selection depend on codend type, also accounting for the potential effect of codend catch size and fishing season. The size selectivity of the two codends was evaluated and compared in identical simulated controlled conditions. Mesh type significantly affected the size selection of Norway lobster alone, with a slightly better performance of the 40 mm square-mesh codend. A high risk of retention of undersized individuals was predicted for both codends for all species except Norway lobster.
We present a framework for Results Based Management (RBM) of commercial fisheries. The core idea ... more We present a framework for Results Based Management (RBM) of commercial fisheries. The core idea of RBM is to reduce micro-management by delegating management responsibility to resource users. The RBM framework represents an industrial organization approach to comanagement and comprises three defining processes, conducted by three independent "agents": 1) an "authority" defines specific and measurable and achievable objectives (outcome targets, OTs) for the utilization of fisheries resources, 2) resource user organizations (termed "operators") take responsibility for achieving these OTs and provide documentation that 3) allows independent "auditors" to evaluate the achievement of OTs. Using incentive mechanisms, notably deregulation, RBM grants operators the flexibility to develop and implement innovative and cost-effective ways to achieve OTs. The feasibility of implementing RBM in five European fisheries was investigated in cooperation with relevant stakeholders through artificial planning processes and computer simulations. The operators involved were enthusiastic, and new management plans were drafted based on the framework. These included socioeconomic OTs in addition to traditional stock objectives, encompassing an ecosystem approach. Several issues are in need of further research in order to consolidate the approach and prepare the ground for practical implementation, including: the specification of the legal and regulatory framework required to underpin RBM, details of transitional arrangements when shifting towards RBM (including cost-sharing) and the development of necessary organizational capacity for operators. Initially, we therefore envisage the framework being applied to high value single species fisheries, with a limited number of participants, which are adequately represented by a competent organization.
Abstract Fisheries involve an intensive use of European maritime regions according to the Common ... more Abstract Fisheries involve an intensive use of European maritime regions according to the Common Fisheries Policy (CFP). The recent CFP reform has adopted an ecosystem-based approach to fisheries management that is characterised by enhanced regionalisation and multi-annual management plans. It aims to avoid the adverse environmental impacts of fishing activities, which are to be mitigated as far as possible, while the wasteful practice of discarding unwanted catches is to be phased out by 2019, at least for species with minimum landing size. The paper investigates the ability of selected measures, envisaged by the CFP reform through the European Maritime and Fisheries Fund (EMFF), to sustain and attain the objectives of the European Marine Strategy Framework Directive, which aims at achieving Good Environmental Status (GES) in marine waters according to an ecosystem-based approach. The analysis uses an expert judgment-based approach and a specially devised questionnaire, where fisheries science and management experts were asked to assess the impact and interaction of selected EMFF measures on GES achievement as defined for the Italian seas. Their responses are discussed and compared with information coming from an extensive literature review. The results of the analysis highlight a general agreement between EMFF actions and GES objectives but also identify some potential conflicts.
Fishing pressure is often expressed in terms of a vessels physical attributes, like tonnage and e... more Fishing pressure is often expressed in terms of a vessels physical attributes, like tonnage and engine power, while a common definition of fishing capacity identifies vessel size as a convenient proxy for the size of the gear used. Nevertheless, these definitions remain arguable, and the refinement of these fishing descriptors is increasingly being considered. A stronger understanding of the relationship between the standard measures of effort and capacity and fishing mortality remains a primary objective, followed by the need to overcome a traditional approach that simply describes effort, capacity and mortality as linearly related, conferring a greater fishing power to larger vessels. In this perspective, the analysis of trawlers' technical features in relation to the size and power of the vessel might constitute an essential step. This study specifically investigated a collection of trawling gears' technical specifications collected by CNR-IRBIM, Ancona. The dataset used includes records from several Mediterranean fisheries, and involves three trawling techniques, including single trawling, twin trawling and pair trawling, and diverse trawling gear categories, comprising demersal/bottom 2-panel trawls (OTB2), demersal/bottom 4-panel trawls (OTB4), pelagic 4-panel trawls (PTM4), semi-pelagic 2-panel trawls (OTM2), semi-pelagic 4-panel trawls (OTM4), and a Mediterranean bottom beam trawl (TBB). We analyzed and described the relationships between vessels' technical features (LOA, towing force, and engine power), some among the main trawl-metrics (headline length, footrope length, trawl length, square width; fishing circle) and the otterboard's technical features (height, width, and projected area) in an attempt to enhance fishing capacity definition through the inclusion of the fishing gear deployed. Self-organizing maps (SOM) were used to explore the empirical relationships among different parts of the fishing trawl gears, as well as between some of these parts, the otterboard size and the engine power of the vessel.
Abstract Fishing is an energy-intensive economic activity. Research in several fields is conducte... more Abstract Fishing is an energy-intensive economic activity. Research in several fields is conducted to improve the energy and environmental profile of fishing vessels. As regards the technical measures, the assessment of benefits is often hampered by boundary conditions that are difficult to quantify and side effects that are difficult to unravel. This study examined the impact of a fluoropolymer-based fouling release paint on the fuel consumption rate of a Mediterranean bottom trawler. The analysis of a series of sea trial campaigns allowed for a quantitative and qualitative comparison of fuel consumption rate during the regular fishing activities. Comparing the fuel consumption rate before and after the application of the fluoropolymer-based foul-release coating, a reduction in fuel consumption rate was observed and quantified. Other advantages are discussed in this paper regarding the reduction of GHG emission, and the more environmental-friendly approach using biocide-free and non-banned products.
The European Food and Nutrition Action Plan 2015–2020 encourages Member States to promote local a... more The European Food and Nutrition Action Plan 2015–2020 encourages Member States to promote local affordable and healthy dietary initiatives to support a sustainable food system, particularly in schools and public institutions where advertising on eating behaviour and food preferences is needed. In Italy, the promotion of healthy and sustainable diets, including the consumption of oily fish, is at an early stage. Based on the success of a unique Italian educational campaign in school lunch programmes, the aim of the present study was to compare the nutritional composition of locally caught anchovy and of imported frozen fillets of farmed Vietnamese pangasius, to observe the potential implications of this dietary substitution. Anchovy showed a significantly higher fatty acid and protein content than pangasius, and contained five times more lipids, mainly n-3 and n-6 polyunsaturated fatty acids. As previous studies confirmed, a diet providing large amounts of these fats is therefore rec...
Despite the fact that Mediterranean loggerhead turtles are listed as "Least Concern" by the Inter... more Despite the fact that Mediterranean loggerhead turtles are listed as "Least Concern" by the International Union for the Conservation of Nature (IUCN), they are among the most threatened marine megafauna worldwide, because of fishery-related incidental captures. The northern central Adriatic Sea is one of the most overfished basins of the Mediterranean Sea and it supports a very valuable marine biodiversity, including sea turtles. This study assesses the spatial and seasonal impact of the northern central Adriatic midwater pair trawl fishery on loggerhead turtle (Caretta caretta) by examining incidental catches recorded between 2006 and 2018 and environmental variables. The model predicted seasonal variation of loggerhead distribution. According to previous studies, data analysis indicates that most bycatch events of loggerhead turtle occurred in the northern Adriatic Sea. The present data confirm that the northern Adriatic may be an important foraging area for loggerhead turtle. They also highlight the urgent need for a better understanding of the interactions between sea turtles and fisheries to develop and apply suitable, ad hoc management measures in critical habitats.
The Mediterranean Sea is a hotspot of biodiversity, but the high fishing pressure results in high... more The Mediterranean Sea is a hotspot of biodiversity, but the high fishing pressure results in high bycatch rates of protected (sea turtles and cetaceans) and top predator species (sharks). The reduction of bycatch is challenging for fishery scientists, as conservation of these species has become a priority. Among the animals threatened by fishing activities, the loggerhead (Caretta caretta) represents a charismatic species considered as “vulnerable” at the global scale by IUCN. In the Mediterranean Sea, trawl nets show the highest probabilities of bycatch of protected species, with high rates of mortality. A new flexible Turtle Excluder Device (TED) has been tested for the first time on a commercial scale in the Mediterranean Sea to assess its effectiveness in reducing bycatch. The results did not show any significant (α = 0.05) loss in terms of commercial weight, but a significant reduction of debris in the codend of the nets mounting the TED respect to traditional nets. The catch c...
Mediterranean trawl fisheries are characterized by a critical combination of high fishing effort ... more Mediterranean trawl fisheries are characterized by a critical combination of high fishing effort and low size at first capture for most commercial species. In this study we tested the use of sorting grids installed on bottom trawl nets to minimize the catch of undersized deep-water rose shrimp (Parapenaeus longirostris, DPS) and European hake (Merluccius merluccius, HKE). The catch of a traditional trawl net was compared with that obtained with the same net equipped with ad hoc designed juveniles and trash excluder devices (JTEDs) during an experimental survey. Three different JTEDs were tested: the first (G1-SM40) was built with a net of 40-mm square mesh; the second (G2-ST20) and third (G3-ST25) with vertical steel bars spaced 20 and 25 mm, respectively. The probability of retaining DPS and HKE by length class in trawl nets with and without JTED was analysed using generalized additive mixed models. With G1-SM40, the reduction of undersized individuals in the cod-end was about 60% ...
Gear selectivity and discards are important issues related to fisheries management but separately... more Gear selectivity and discards are important issues related to fisheries management but separately modelled. This work examines for the first time the overall size-selection pattern on the total amount of individuals of a species entering the trawl codend. An innovative approach was used based on modelling the escapement through the codend in the sea and the subsequently selection process by the fisher on the deck of the fishing vessel resulting into the discards and landings. Three different trawl codends and three species were investigated in the case study conducted. A dual sequential model accounting for both gear size-selectivity and the subsequent fisher-size-selectivity was applied, under the hypothesis that a fish entering the codend can follow a multinomial distribution with three probabilities, the escape, the discard and the landing probability, respectively. The model described the escape probability through the gear and the landing probability by the fisher as S-shaped c...
Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental c... more Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus), spiny dogfish (Squalus acanthias), common eagle ray (Myliobatis aquila), and pelagic stingray (Pteroplatytrygon violacea) by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures.
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Papers by Antonello Sala