rim19_5Author / Editor: Stéfani Novoa, Guillem Chust, Yolanda Sagarminaga, Marta Revilla, Javier Franco, Victoriano Valencia and Ángel Borja (AZTI-Tecnalia)

Year: 2012

Content: Understanding the response of chlorophyll-a (as a proxy for phytoplankton biomass) to both anthropogenic pressures and natural factors is important for water quality assessment purposes and for the management of biological resources. In the Basque coastal area, discharges produced by the Adour and Nervión rivers (south-eastern part of the Bay of Biscay) have been proven to reach up to 15-20 km off the coast. The first objective of this study was to describe the spatial and temporal variability of chlorophyll-a in the Basque coast and the Bay of Biscay, in relation to river discharges at a daily, seasonal and inter-annual scale using MODIS images acquired between 2005 and 2010. The second objective was to offer a synoptic description of the spatio-temporal variability of chlorophyll-a in the entire Bay of Biscay, using multivariate statistical methods and satellite imagery. The results indicate that seasonal chlorophyll-a cycle is slightly different in coastal areas affected by the Adour and the Nervión river waters, compared to offshore waters. The spring chlorophyll-a peak in March in offshore waters shifts to May in the Adour nearby area Nervión. The multivariate statistical analysis highlights the influence of river discharges in the spatial variability of chlorophyll-a in coastal areas of the bay. The Spanish and French Basque coastal waters are differentiated in terms of chlorophyll-a concentrations levels reached, river regimes and morphology of the continental shelf. Statistical and indicator maps have been created to represent the main components of chlorophyll-a variability in the area of study. They confirm that, at present, phytoplankton is at good status and eutrophication risk is low in the Basque coastal waters. These maps may provide water quality indicators in a continuous spatial distribution in the area and may be used for the selection of water quality stations as a function of the dynamics of the water masses characterised.

Contact: biblioteca@azti.es

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rim19_3Author / Editor: Ángel Borja, Julien Mader, Iñigo Muxika (AZTI-Tecnalia)

Year: 2012

Content: The AZTI’s Marine Biotic Index (AMBI) was developed in 2000. Some years later a software was created for the calculation and made available in the page http://ambi.azti.es. Several versions of this freely available software have been created. In this paper we explain the new AMBI 5.0 version, for Windows 7, which has some novelties regarding the import of data for the calculation, the change of species and the process of saving all the information. Moreover, a new species list, with more than 6300 species from the entire world has been included.

Contact: biblioteca@azti.es

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rim19_4Author / Editor: Manuel González, Pedro Liria, Juan Amate, Jaime Domínguez andMaría C. Uyarra

Year: 2012

Content: Based on a detailed analysis of the regional and global variability ranges in the existing estimates of the theoretical potential of marine energy, a simple classification for the energy potential of currents, tides and waves is proposed. In the classification of the energy potential of currents, only “high potential” sites (i.e. peak currents > 2.5 m.s-1) and “very high potential” sites (i.e peak current > 4 m.s-1) are considered, taking into account the existing technology, as suitable sites for the installation of turbines and capture of energy. Regarding the energy potential of tides, only potential energy (versus kinetic) is considered; the classification of tides follows the classical oceanographic classification (i.e. microtidal, low mesotidal, high mesotidal, low macrotidal and high macrotidal), with the macrotidal range (i.e. tidal range > 5.5 m) being suitable for energy production. The classification of the energy potential of waves is based on an energy criteria; the annual average wave power flux. Based on this criteria most of the Spanish Mediterranean coast would be classified as having “low potential” (i.e. <5 kW.m-1), the Canary Islands and the Gulf of Cadiz as having “medium potential” (i.e. between 5 and 15 kW.m-1) and the Cantabrian and Galician coast as being “high potential” sites (i.e. between 15 and 45 kW.m-1). Other sites with annual average wave power flux higher than 45 kW.m-1, (e.g., Australia, South Africa, Ireland, etc.), would be classified as “very high potential” sites.

Contact: biblioteca@azti.es

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rim19_2Author / Editor: Ibon Galparsoro (Editor invitado). AZTI-Tecnalia

Year: 2012

Content: This publication collets the abstract of the Workshop held on 23 and 24 April at the Aquarium of San Sebastián, Spain. This Workshop, organized within the MeshAtlantic project action plan (Mapping European Seabed Habitat Maps in the Atlantic area; InterReg Atlantic Area Transnational Programme of the European Regional Development Fund; www.meshatlantic.eu), focused mainly upon the experience of different scientists and case studies, using the EUNIS (the European Nature Information Service) habitat classification.

The benefits and problems arisen in the application of the classification were highlighted, whilst the necessary improvements to make it ecologically-meaningful and to be used by managers and decision-makers were discussed. New biotope classes observed in the field, poorly represented biogeographic areas such as the southwestern European seas (with a particular focus on the Atlantic Area region, the Bay of Biscay and the Azores) and the deep-sea realm, were also considered.

Contact: biblioteca@azti.es

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rim19_1Author / Editor: Eneko Bachiller (AZTI-Tecnalia)

Year: 2012

Content:  In trophic studies of small pelagic fish, comparisons between gut contents and the available food in field are commonly limited by the sampling procedure. In this sense, different sized zooplankton samples can differ depending on the mesh size of the sampling net. In the same way, the variability on the distribution of both predators and preys as a function of environmental variables can be a limiting factor when taking samples and hence, that could be reflected in stomach contents. In this study different aspects are discussed in order to optimize the sampling design addressing trophic studies in the Bay of Biscay, presenting also unpublished information about the distribution of both zooplankton and the main small pelagic species.

This way, it is observed that 63 µm and 150 µm mesh Pairovet nets are not enough to catch the whole prey size spectrum found in stomachs of fish. In addition, many geographical areas are proposed in order to detect the variability of the distribution of both predators and preys; in the same way, the importance of sampling in different time ranges is discussed, as well as the regurgitation problem that long trawls could suppose for fish due to the stress caused. Finally, since stomach contents can differ from one fish to other, the significance of the individual fish analysis is highlighted, defining the optimum minimum sample size in order to detect a significant percentage of the prey diversity found in different small pelagic species.

Contact: biblioteca@azti.es

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rim18_7Author / Editor: Nagore Cuevas, Joana Larreta, José Germán Rodríguez and Izaskun Zorita (AZTI-Tecnalia)

Year: 2011

Content:  Imposex assessment (imposition of male characters in female dioecious gastropods due to organotin compounds) in two gastropod species, Nassarius reticulatus and Nassarius nitidus, is detailed by a visual guideline. The information that appears in different sections is accompanied by photographs, diagrams and data summary reports with the aim of solving the doubts that can arise in the process of imposex evaluation. Additionally, this guideline also reviews alternative imposex classification indices currently in use

Contact: biblioteca@azti.es

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rim18_5Author / Editor: María Santos, Andrés Uriarte, Leire Ibaibarriaga (AZTI-Tecnalia)

Year: 2011

Content:  The research survey BIOMAN2010 for the application of the Daily Egg Production Method (DEPM) for the Bay of Biscay anchovy was conducted in May 2010, from the 5th to the 20th, covering the whole spawning area of the population. Total egg production was calculated as the product of the spawning area and the daily egg production rate, which was obtained from the exponential decay mortality model fitted as a Generalised Linear Model (GLM) to the egg daily cohorts. The adult parameters: sex ratio, batch fecundity and weight of mature females, were estimated from the adult samples obtained during the survey and the spawning frequency was calculated as the mean from the historical series. The spawning biomass estimate resulted in 42,979 t with a coefficient of variation of 15%, which supposes an increase of about 73% over the SSB estimate of 2009 produced in a similar way by the DEPM.

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rim18_3Author / Editor: Iñaki Quincoces, Luis Arregi, Mikel Basterretxea, Ibon Galparsoro, Joxe Mikel Garmendia, Jesús Martínez, José Germán Rodríguez, Ainhize Uriarte (AZTI-Tecnalia)

Year: 2011

Content: The European Marine Strategy Framework Directive (Directive 2008/56/EC), establishes a framework and common objectives for the protection and conservation of the marine environment. This Directive requires the implementation of all measures necessary to achieve the Good Environmental Status by 2020, according to 11 qualitative descriptors: (i) biodiversity, (ii) non-native species, (iii) commercial species, (iv) food webs, (v) eutrophication, (vi) seabed integrity, (vii) hydrography, (viii) pollutants, (ix) contaminants in biota, (x) marine litter and (xi) energy and noise (European Commission, 2008). With the aim of improving the knowledge of the environmental status of the Basque coast, in relation to the descriptors i, ii, iii, iv and vi, a new survey named Cape Breton 2010 and deployed by AZTI-Tecnalia was carried out, using the Gure Gaskuña vessel. The information produced here will be used to meet the information required which was detected in a preliminary assessment of the environmental status performed by Borja et al. (2011). Demersal fauna was sampled undertaking 22 trawls, and 24 grab samples were collected for substratum and macrofauna characterization. The sampled depth ranged from 30 m to 359 m and the area surveyed with trawls was 7.21 km2.

A total of 72 species of fish and cephalopods, and 59 taxa of epibenthic invertebrates were identified by trawling survey sampling; whereas a total of 360 taxa of macroinvertebrates were identified in the grab samples. Two types of fish communities were identified depending on depth and substrate type. One of them was located at shallow-waters and it was characterized by a greater diversity of species; the other one was located at deeper water depth and it was characterized by lower species diversity and a clear dominance of few species in terms of biomass. Merluccius merluccius was found in all tows. Dominant species, in terms of biomass, of fish and invertebrates of commercial interest were: Trachurus trachurus, Scyliorhinus canicula, Micromesistius poutassou, Raja clavata and Merluccius merluccius. The most common invertebrates collected during the survey were found to be: Psilaster andromeda, Ophiura ophiura, Marthasterias glacialis, Parastichopus regalis and Pagurus alatus. Finally, the macrofauna taxa with greater presence were: Paradiopatra calliopae, Galathowenia oculata, nemerteans, Mediomastus fragilis, Terebellides stroemii, Sagitta sp., Copepoda, Poecilochaetus serpens and Monticellina dorsobranchialis. The structural parameters of the macrofauna showed a significant relationship with depth and sediment characteristics.

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rim18_6Author / Editor: Guzmán Díez, Estibaliz Díaz, Luis Arregi, Yolanda Sagarminaga, Xabier Irigoien, Paula Álvarez, Unai Cotano, Hilario Murua, María Santos, Arantxa Murillas and Ibon Galparsoro (AZTI-Tecnalia)

Año: 2011

Content: The presence at the beginning of 2003 in the Bay of Biscay of huge amount from the Prestige wreck occurred in November 2002 in Galicia waters, led to carry out in the affected area a study to assess at the short and medium term the effects of the oil spill in the fisheries and in the trophic chain.

More specifically, the aim of the experimental design was focused to assess the PAHs (Polycyclic Aromatic Hydrocarbons) effects in the life cycle and population structure of two representative demersal and pelagic fish species; hake (Merluccius merluccius) and anchovy (Engraulis encrasicolus). The study included the analysis of relevant biological indicators of toxicological effects of species (histopathological prevalence, tisular concentration of PAHs, larval condition and alterations in the fertility) and also the evaluation of the status in the lowest trophic levels as chlorophyll and zooplankton abundance. Whenever possible the studies tried to compare the biological effects recorded at short-medium term after the oil spill with a historical review of the levels of biological parameters described.

The project was supported by several surveys that allowed collecting enough samples for the biological studies and also for a GIS database designed for the management and presentation of the project results. To estimate the possible loss of income by fishermen and the changes made in the demand fish as result of the oil spill, the project also included a socio-economic study focused on three species targeted by the Basque artisanal fleet.

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RIM17(6): Enfoque multivariante para la definición de metiers: caso de estudio de la flota de arrastre de altura del País Vasco

Author / Editor: Ane Iriondo, Raúl Prellezo, Marina Santurtún, Dorleta García, Iñaki Quincoces and Estanis Mugerza (AZTI-Tecnalia)

Year: 2010

Content: In this paper a classification into metiers of the trawling fleet of the Basque Country (North East of Spain) operating in the Northeast Atlantic ICES Subareas VI, VII, and Divisions VIIIa,b,d from 2003 to 2008 is presented. Principal Component Analysis (PCA) and Cluster analysis approach are used to obtain homogeneous groups of metiers using trip by trip catch data information. The characterization of these groups is based on target species, fishing area, gear and period of the year. After analyzing the clusters obtained and taking into account the knowledge of the fishery, seven Basque trawl metiers are proposed: 1) pair trawl in Divisions VIIIa,b,d targeting demersal fish, 2) otter trawl in Divisions VIIIa,b,d targeting demersal fish , 3) otter trawl in Divisions VIIIa,b,d targeting mixed cephalopods and demersal fish 4) otter trawl in Division VIIIa,b,d targeting horse mackerel, 5) otter trawl in Divisions VIIIa,b,d targeting mackerel, 6) otter trawl in Subarea VII targeting megrim and monkfish, 7) otter trawl in Subarea VI targeting hake, megrim and monkfish and seasonally blue ling. Five of them are considered consistent along the years 2003-2008 and two of them are seasonal.

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