Marina Santurtun | AZTI Tecnalia (original) (raw)

Uploads

Papers by Marina Santurtun

John Wiley & Sons, Ltd eBooks, Sep 11, 2015

Industrias Pesqueras: revista marítima quincenal, 2019

CM Documents - ICES, 1998

Canadian Journal of Fisheries and Aquatic Sciences, Mar 1, 2006

The scope of this paper is to quantify, for a wide selection of European fisheries, fishing tacti... more The scope of this paper 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 métiers 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 fishing 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. Adjusting fishing effort by means of (i) the métier effect and (ii) the indices of tactics and strategies generally led to a substantial gain in the precision of the relationship between fishing mortality and fishing effort.

Research Square (Research Square), Aug 10, 2023

The European anchovy Engraulis encrasicholus is one of the most commercial important species in t... more The European anchovy Engraulis encrasicholus is one of the most commercial important species in the Bay of Biscay (ICES Subarea 8). We analysed the temporal mean abundance of Anisakis spp. larvae

Parasitology Research, Apr 25, 2022

We analysed the spatial and temporal variability of Anisakis larvae infection in hake (Merluccius... more We analysed the spatial and temporal variability of Anisakis larvae infection in hake (Merluccius merluccius) from the North-East Atlantic from 1998 to 2020 and the potential drivers (i.e., environmental and host abundance) of such variation. The results showed that hake from separate sea areas in the North Atlantic have marked differences in temporal abundance levels. Hake larger than 60 cm were all parasitized in all ICES (International Council for the Exploration of the Sea) subareas 6, 7, and 8. The belly flaps were the most parasitized parts of the flesh, accounting for 92% of the total. Individuals of Anisakis simplex, Anisakis pegreffii, Anisakis spp. and a hybrid of Anisakis simplex × pegreffii were genetically identified, and Anisakis simplex as the most abundant (88-100%). An ecological niche model of Anisakis occurrence in fishes in the NE Atlantic was built to define the thermal optimum and environmental ranges for salinity, depth, chlorophyll concentration, and diffuse attenuation. The temporal variability of anisakid infection in fishes in the last two decades indicated an increase in the NE Atlantic at an annual rate of 31.7 nematodes per total number of specimens examined per year. This rise in infection levels could be triggered by the increase in intermediate host fish stocks, especially hake in the area.

Cephalopods are short-lived fast growing species which are highly sensitive to environmental vari... more Cephalopods are short-lived fast growing species which are highly sensitive to environmental variation, as reflected in wide year-to-year fluctuations in abundance. Understanding the relative importance of environmental variation and fishing mortality in determining stock trajectories is essential to underpin appropriate management measures and support sustainable exploitation of these species. Over three decades ICES WGCEPH has reported on patterns and trends in cephalopod landings in the ICES area but there has been no comprehensive analysis of patterns and trends. We assembled data series on loliginid squid, ommastrephid squid, octopus and cuttlefish from landings (where possible considering landings per unit effort) and survey catches. For most series it is not possible to be sure of the cephalopod species involved so the main analysis is at family level.

ICES Annual Science Conference, 9-12 September 2019, Gothenburg, SwedenPeer reviewe

ICES Journal of Marine Science

With increasing activities of multiple sectors in marine spaces, management of marine social–ecol... more With increasing activities of multiple sectors in marine spaces, management of marine social–ecological systems requires more holistic approaches. Adopting such an approach, however, presents difficult institutional and disciplinary challenges. Here, we use the International Council for the Exploration of the Sea (ICES) as a case study on the implementation of ecosystem-based management (EBM) and integrated ecosystem assessments (IEAs). ICES includes EBM and IEAs in its Science Priorities and established IEA Working Groups (WGs) to carry out regional IEAs. But to what degree does this IEA WG work follow best practices? We examine policy documents, academic literature, and interview data from chairs of all IEA WGs. Results indicate mixed success. All groups acknowledge the holistic goals of IEA, and many use the IEA model as laid out by Levin et al. However, we found a significant variation in the degree to which the full model is applied. We identified two primary areas for improvem...

Acta Parasitologica, 2022

PURPOSE It has been suggested that the removal of infected viscera on board is responsible for th... more PURPOSE It has been suggested that the removal of infected viscera on board is responsible for the high prevalence of anisakid larvae present in wild fish species. The aim of this work is to assess the re-infection capacity of anisakid larvae in European seabasses, a natural host species for the parasite by feeding with pieces of parasitised hake liver under controlled experimental conditions. METHODS To prove this potential link between manipulation and re-infestation, 50 farmed seabasses free of anisakid nematodes were fed with fresh hake liver pieces naturally infested with anisakid larvae. RESULTS After digestion periods from 4 to 21 days, the seabasses showed a prevalence of Anisakis of 6%, and a low retention rate of 0.11 larvae/seabass after four days' digestion, and 0.0021 after 21 day digestion. Two nematodes were found in the intestine and in the visceral cavity, and 13 Anisakis were found partially digested in the stomach of one same individual after 4 day digestion. Results showed that only a small number of Anisakis ingested with the viscera were able to reinfect the seabasses, as most of the larvae seemed to be quickly digested or defecated. CONCLUSION it seems that the availability of larvae that could re-enter the life cycle and re-infect a fish after the removal and discarding the infected viscera on board could be much less important than commonly believed.

CM Documents - ICES, 1998

Ecography, 2011

Fisheries ecologists traditionally aimed at disentangling climate and fishing effects from the po... more Fisheries ecologists traditionally aimed at disentangling climate and fishing effects from the population dynamics of exploited marine fish stocks. However, recent studies have shown that internal characteristics and external forcing (climate and exploitation) have interactive rather than additive effects. Thought most of these studies explored how demographic truncation induced by exploitation affected the response of recruitment to climate, identifying a general pattern revealed to be difficult as interactions are often case‐specific. Here we compared five exploited stocks of European hake Merluccius merluccius from the Atlantic Ocean and Mediterranean Sea to investigate how the interaction between internal characteristics and external forces affect the variability of the population growth rate and their consequences on recruitment. Our results show that demographic truncation induces a novel population scenario in which the growth rate is maximized when the reproductive stock is ...

Fishing is an economic activity that is intrinsically dependent on the productivity of the marine... more Fishing is an economic activity that is intrinsically dependent on the productivity of the marine environment. Maintaining fishing resources at levels that can sustain the fishing activity requires setting long-term goals that may sometimes not be compatible with the short-term interests of the fishing industry, and political and economic factors. In the EU, the course of the fishing sector is not only influenced by the evolution of the Common Fisheries Policy (CFP), and its reforms, but also by market conditions, availability of fish in EU waters, and accessibility to non-EU waters. These factors impose challenges for EU policy-makers. KEY FINDINGS

John Wiley & Sons, Ltd eBooks, Sep 11, 2015

Industrias Pesqueras: revista marítima quincenal, 2019

CM Documents - ICES, 1998

Canadian Journal of Fisheries and Aquatic Sciences, Mar 1, 2006

The scope of this paper is to quantify, for a wide selection of European fisheries, fishing tacti... more The scope of this paper 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 métiers 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 fishing 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. Adjusting fishing effort by means of (i) the métier effect and (ii) the indices of tactics and strategies generally led to a substantial gain in the precision of the relationship between fishing mortality and fishing effort.

Research Square (Research Square), Aug 10, 2023

The European anchovy Engraulis encrasicholus is one of the most commercial important species in t... more The European anchovy Engraulis encrasicholus is one of the most commercial important species in the Bay of Biscay (ICES Subarea 8). We analysed the temporal mean abundance of Anisakis spp. larvae

Parasitology Research, Apr 25, 2022

We analysed the spatial and temporal variability of Anisakis larvae infection in hake (Merluccius... more We analysed the spatial and temporal variability of Anisakis larvae infection in hake (Merluccius merluccius) from the North-East Atlantic from 1998 to 2020 and the potential drivers (i.e., environmental and host abundance) of such variation. The results showed that hake from separate sea areas in the North Atlantic have marked differences in temporal abundance levels. Hake larger than 60 cm were all parasitized in all ICES (International Council for the Exploration of the Sea) subareas 6, 7, and 8. The belly flaps were the most parasitized parts of the flesh, accounting for 92% of the total. Individuals of Anisakis simplex, Anisakis pegreffii, Anisakis spp. and a hybrid of Anisakis simplex × pegreffii were genetically identified, and Anisakis simplex as the most abundant (88-100%). An ecological niche model of Anisakis occurrence in fishes in the NE Atlantic was built to define the thermal optimum and environmental ranges for salinity, depth, chlorophyll concentration, and diffuse attenuation. The temporal variability of anisakid infection in fishes in the last two decades indicated an increase in the NE Atlantic at an annual rate of 31.7 nematodes per total number of specimens examined per year. This rise in infection levels could be triggered by the increase in intermediate host fish stocks, especially hake in the area.

Cephalopods are short-lived fast growing species which are highly sensitive to environmental vari... more Cephalopods are short-lived fast growing species which are highly sensitive to environmental variation, as reflected in wide year-to-year fluctuations in abundance. Understanding the relative importance of environmental variation and fishing mortality in determining stock trajectories is essential to underpin appropriate management measures and support sustainable exploitation of these species. Over three decades ICES WGCEPH has reported on patterns and trends in cephalopod landings in the ICES area but there has been no comprehensive analysis of patterns and trends. We assembled data series on loliginid squid, ommastrephid squid, octopus and cuttlefish from landings (where possible considering landings per unit effort) and survey catches. For most series it is not possible to be sure of the cephalopod species involved so the main analysis is at family level.

ICES Annual Science Conference, 9-12 September 2019, Gothenburg, SwedenPeer reviewe

ICES Journal of Marine Science

With increasing activities of multiple sectors in marine spaces, management of marine social–ecol... more With increasing activities of multiple sectors in marine spaces, management of marine social–ecological systems requires more holistic approaches. Adopting such an approach, however, presents difficult institutional and disciplinary challenges. Here, we use the International Council for the Exploration of the Sea (ICES) as a case study on the implementation of ecosystem-based management (EBM) and integrated ecosystem assessments (IEAs). ICES includes EBM and IEAs in its Science Priorities and established IEA Working Groups (WGs) to carry out regional IEAs. But to what degree does this IEA WG work follow best practices? We examine policy documents, academic literature, and interview data from chairs of all IEA WGs. Results indicate mixed success. All groups acknowledge the holistic goals of IEA, and many use the IEA model as laid out by Levin et al. However, we found a significant variation in the degree to which the full model is applied. We identified two primary areas for improvem...

Acta Parasitologica, 2022

PURPOSE It has been suggested that the removal of infected viscera on board is responsible for th... more PURPOSE It has been suggested that the removal of infected viscera on board is responsible for the high prevalence of anisakid larvae present in wild fish species. The aim of this work is to assess the re-infection capacity of anisakid larvae in European seabasses, a natural host species for the parasite by feeding with pieces of parasitised hake liver under controlled experimental conditions. METHODS To prove this potential link between manipulation and re-infestation, 50 farmed seabasses free of anisakid nematodes were fed with fresh hake liver pieces naturally infested with anisakid larvae. RESULTS After digestion periods from 4 to 21 days, the seabasses showed a prevalence of Anisakis of 6%, and a low retention rate of 0.11 larvae/seabass after four days' digestion, and 0.0021 after 21 day digestion. Two nematodes were found in the intestine and in the visceral cavity, and 13 Anisakis were found partially digested in the stomach of one same individual after 4 day digestion. Results showed that only a small number of Anisakis ingested with the viscera were able to reinfect the seabasses, as most of the larvae seemed to be quickly digested or defecated. CONCLUSION it seems that the availability of larvae that could re-enter the life cycle and re-infect a fish after the removal and discarding the infected viscera on board could be much less important than commonly believed.

CM Documents - ICES, 1998

Ecography, 2011

Fisheries ecologists traditionally aimed at disentangling climate and fishing effects from the po... more Fisheries ecologists traditionally aimed at disentangling climate and fishing effects from the population dynamics of exploited marine fish stocks. However, recent studies have shown that internal characteristics and external forcing (climate and exploitation) have interactive rather than additive effects. Thought most of these studies explored how demographic truncation induced by exploitation affected the response of recruitment to climate, identifying a general pattern revealed to be difficult as interactions are often case‐specific. Here we compared five exploited stocks of European hake Merluccius merluccius from the Atlantic Ocean and Mediterranean Sea to investigate how the interaction between internal characteristics and external forces affect the variability of the population growth rate and their consequences on recruitment. Our results show that demographic truncation induces a novel population scenario in which the growth rate is maximized when the reproductive stock is ...

Fishing is an economic activity that is intrinsically dependent on the productivity of the marine... more Fishing is an economic activity that is intrinsically dependent on the productivity of the marine environment. Maintaining fishing resources at levels that can sustain the fishing activity requires setting long-term goals that may sometimes not be compatible with the short-term interests of the fishing industry, and political and economic factors. In the EU, the course of the fishing sector is not only influenced by the evolution of the Common Fisheries Policy (CFP), and its reforms, but also by market conditions, availability of fish in EU waters, and accessibility to non-EU waters. These factors impose challenges for EU policy-makers. KEY FINDINGS