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P>1. The development of ecosystem approaches to environmental management implies the need to account for multiple pressures on ecosystems. Trends in multiple metrics that respond differently to changes in major environmental pressures need to be combined to evaluate the impacts of fishing and environmental changes on fish communities. 2. An exploited fish community is viewed as a three-level food chain in which the two upper levels, or functional groups, are targeted by fishing fleets, while the lowest level is subject to environmental variation. Qualitative modelling is used to predict changes at the two upper levels, that is, top-down vs. bottom-up perturbations. Abundance and length metrics are calculated from survey data for 14 Mediterranean and East-Atlantic groundfish shelf communities at both population and functional group levels. The joint likelihood of time trends in metrics is used to evaluate the evidence for different causes of changes. 3. A wide diversity of impacts is found to have equal evidence at the population level within each community. Consistency between the impacts identified and changes in pressures known from independent information is found at the functional group and community level. The results suggest that there is some compensation between species within functional groups. 4. Synthesis and applications. The method can be used to conduct an integrated assessment of community dynamics subject to multiple pressures. Joint trends in metrics provide evidence of which known pressures are having an impact on the community, and thus, which management actions should be taken to mitigate these changes.

Deepwater fisheries pose particular difficulties for management. Target species are difficult to assess with adequate levels of certainty, they are slow growing and generally vulnerable to overfishing and many of these fisheries reside outside EEZs and are, therefore, not subject to national jurisdictions. The EU project DEEPFISHMAN will develop a range of strategy options for the management of deepwater fisheries in the NE Atlantic that will take account of these factors. The primary objective of the project is to identify and develop new and more effective assessment methods, reference points, control rules and management strategies to be used in the short term. The second objective is to develop a long-term research and management framework in which additional data needs will be specified in order to fill current information gaps to achieve reliable long-term management requirements. This research effort will be supported by a range of case studies selected to reflect the characteristics of the different types of deepwater fisheries found in the NE Atlantic. In addition, two case studies outside the NE Atlantic are selected to give a wider perception of the management and monitoring of deepwater fisheries in the world. Case studies will collate, store, combine and raise data to appropriate fisheries/stocks levels. The socio-economic aspect of the fisheries and the expected impact of the management strategy options will be examined. The project outputs will aim to provide robust guidelines for deepwater fisheries management suitable for adoption within the Common Fishery policy. Keywords: Deep-water fisheries, EU project

Politou, Chrissi-Yianna, Mytilineou, Chryssi, D, Gianfranco, Onghia, Dokos, John (2008): Demersal faunal assemblages in the deep waters of the eastern Ionian Sea. Journal of Natural History 42 (5-8): 661-672, DOI: 10.1080/00222930701835613, URL: http://dx.doi.org/10.1080/00222930701835613

This document is the fifth version of a manual elaborated in the frame of an international project to harmonise the samplings by bottom trawling of the demersal resources in the Mediterranean Sea (MEDITS program). It is the reference document for the surveys to be conducted from 2007 onwards by the research institutes contributing in the Medits surveys on the continental shelves and slopes in the Mediterranean (Fig. 1). The manual describes the sampling gear characteristics, the sampling methodology and the treatment of the samples. Finally it gives the specifications of the data files for data storage and exchange.

This document presents a comparative study of human impacts on the length-structure of fish communities across North-Mediterranean ecosystems. We use survey data to examine trends in length-based metrics and their consistency within and among the two levels of organisation populations and communities, and to suggest interpretations of observed trend combinations. We start from a set of population processes potentially affected by human pressures: fishing will induce mortality especially in target species, whereas the hydrological environment and eutrophication potentially affect recruitment and individual growth. How population changes will be reflected at the community level is expected to depend on community evenness. Based on this expectation, a tentative theory for predicting the joint response of a suite of population and community length-based metrics to potential changes in the environment is proposed. The trends in these metrics from survey data are then examined, focusing on the consistency with the above predictions. The potential causes suggested for the observed trends are then checked against independent evidence of environmental and human pressures on these communities. The approach is applied to the MEDITS survey data, which cover a series of neighbouring fish communities undergoing various human pressures, including fishing, coastal pollution and eutrophication, and a possible change in temperature and hydrology over the last decade.

The object of the DESEAS Project, funded by the EC, was to gather preliminary data on the abundance and maximum depth distribution of the rose shrimp Aristeusantennatus in the Mediterranean Sea. An exploratory survey was therefore designed with that goal in mind and conducted on the R/V García del Cid, sampling the maximum depths in three specific areas in the central and western Mediterranean, one off Ibiza (Balearic Islands), one off Calabria (western Ionian Sea), and one off the southern Peloponnesian Peninsula (Gulf of Kalamata, eastern Ionian Sea). The depths sampled ranged from 600 to 4000 m, with specimens of A. antennatus being collected down to 3300 m. There were three distinct boundaries marking the abundance of this species: < 1000 m, relatively high abundance (up to 1000 ind km-2); 1000-1500 m, relatively moderate abundance (up to 300 ind km-2); and > 1500 m, relatively low abundance (, El objetivo del proyecto DESEAS, financiado por la CE, fue obtener datos preliminares de abundancia y distribución de profundidad máxima de la gamba rosada Aristeus antennatus en el Mar Mediterráneo. El diseño de la campaña exploratoria fue realizado con este propósito y se desarrolló a bordo del B/O García del Cid. Se realizaron muestreos en las máximas profundidades de tres áreas específicas en el Mediterráneo occidental y central: una cerca de Menorca (Islas Baleares), otra frente a las costas de Calabria (Iónico occidental) y la última al sur de la península del Peloponeso (en el Golfo de Kalamata, Iónico oriental). Las profundidades muestreadas fueron las comprendidas entre 600 y 4000 m, obteniendo individuos de A. antennatus hasta 3300 m. Se detectaron tres niveles de abundancias diferenciados en esta especie: < 1000 m, relativamente muy abundante (hasta 1000 ind km-2); 1000-1500 m, abundancia relativamente moderada (hasta 300 ind km-2); > 1500 m, relativamente poco abundante (< 100 ind km-2). En las tres áreas estudiadas se confirmó la estructura de la población conocida hasta el momento, es decir, aumento de la proporción de machos y juveniles con la profundidad. No se encontraron evidencias de diferencias en el desarrollo gonadal o en la presencia de espermatóforos de las hembras entre áreas. Finalmente se observó la existencia de una tendencia en el aumento de la proporción de juveniles con la profundidad.

Data on the distribution, abundance and biological parameters of the giant red shrimp Aristaeomorphafoliacea were collected during a research survey in deep waters (600-4000 m) of the Mediterranean Sea at three locations: the Balearic Sea, the western Ionian and the eastern Ionian in early summer 2001. The shrimp was mainly found in the shallower zone (< 1000 m) of the eastern Ionian Sea. Few specimens were caught in the deeper waters of this region, with 1100 m being the lower limit of its distribution. This is the maximum depth reported for the species in the Mediterranean. At the other two locations, the species was scarcely caught and only in the shallowest zone (< 1000 m). In the area and depth zone of high abundance, 5 modal groups for females and 3 for males were distinguished using the Bhattacharya method. The recruitment seems to take place at the shallowest stations (600 m). More than 50% of adult females were in advanced maturity stages. The striking abundance differences of the species between the western and eastern locations may be explained by the different exploitation level of the deep waters (almost null in the eastern Ionian Sea and extensive more westwards). However, the distribution and biological characteristics of A.foliacea indicate a higher vulnerability to over-fishing comparing to the other commercial co-occurring deep-water shrimp Aristeusantennatus., Se obtuvieron datos sobre distribución, abundancia y parámetros biológicos de la gamba gigante Aristaeomorpha foliacea durante una campaña de investigación en aguas profundas (600-4000 m) en tres localidades a lo largo del Mediterráneo: región Balear, Iónico occidental y Iónico oriental, que tuvo lugar en verano de 2004. Esta gamba fue encontrada mayoritariamente en la zona menos profunda (< 1000m) del Iónico oriental. En aguas más profundas de esta región (1100 m) se encontraron menos ejemplares, pero determinó el límite inferior de su distribución. Esta es la máxima profundidad registrada en el Mediterráneo para esta especie. En las otras dos localidades, esta especie fue escasa y solo se encontró en la zona menos profunda (< 1000 m). En el área y en la profundidad de máxima abundancia, se observaron 5 grupos modales de hembras y 3 de machos mediante el método de Battacharya. El reclutamiento parece que tiene lugar en aguas menos profundas (600 m). Más del 50% de las hembras adultas se encontraron en avanzado estado de madurez gonadal. Esta curiosa diferencia entre la parte más occidental y las localidades más orientales puede explicarse por el diferente nivel de explotación en las aguas profundas (casi nulo en el Iónico oriental e intensivo más al oeste). Sin embargo, la distribución y características biológicas de A. foliacea indican una vulnerabilidad alta a la sobre-explotación pesquera si la comparamos con otras especies de gambas comerciales profundas como Aristeus antennatus.

During an EC-funded research carried out in the Mediterranean Sea deep-water fish (600-4000 m) were collected in the Balearic Sea as well as the western and eastern Ionian Sea. Caelorhynchusmediterraneus is a new record for the Balearic Sea, Cyclothone braueri, Hygophum benoiti, Paralepis speciosa, Chalinura mediterranea, Coryphaenoides guentheri, C. mediterraneus, Lepidion lepidion and Cataetyx laticeps for the western Ionian Sea, and Polyacanthonotus rissoanus, C. guentheri, C. mediterraneus, L. lepidion and C. laticeps for the eastern Ionian Sea. The bathymetric distribution of other species has been updated. Species richness decreased with depth in the three surveyed areas, showing a significant shift below 1500 m. At depths greater than 1000 m macrourid and morid species were dominant except in the Balearic Sea, where Alepocephalus rostratus was found to be very abundant as deep as 1500 m. At depths greater than 1500 m the dominant species were Bathypterois mediterraneus, C. mediterranea and C. guentheri. The results of this research confirm the scarcity of deep fish fauna in the Mediterranean compared to the Atlantic. For the greatest depths are concerned, the faunistic difference between the western and eastern Mediterranean seems to be most probably due to a lesser number of investigations on the eastern side rather than any real paucity of ichthyofauna., Se recolectaron especies de peces en el mar Balear y en el Iónico oriental y occidental, gracias a una investigación subvencionada por la CE en aguas profundas del Mediterráneo (600-4000 m). Caelorhynchus mediterraneus es una nueva cita para el mar Balear, Cyclothone braueri, Hygophum benoiti, Paralepis speciosa, Chalinura mediterranea, Coryphaenoides guentheri, C. mediterraneus, Lepidion lepidion y Cataetyx laticeps lo son para el mar Iónico occidental, Polyacanthonotus rissoanus, C. guentheri, C. mediterraneus, L. lepidion y C. laticeps para el mar Iónico oriental. También se ha puesto al día la distribución batimétrica de otras especies. En las tres áreas muestreadas se ha observado que la riqueza específica desciende con la profundidad, marcándose un cambio significativo por debajo de los 1500 m. A profundidades superiores a 1000 m las especies de macrúridos y móridos fueron dominantes excepto para el mar Balear donde Alepocephalus rostratus fue la especie más abundante hasta 1500 m. A profundidades superiores a los 1500 m las especies dominantes fueron Bathypterois mediterraneus, C. mediterranea y C. guentheri. Los resultados confirman la escasez de ictiofauna profunda en el Mediterráneo comparada con la del Atlántico. Hasta las máximas profundidades muestradas, la diferencia faunística entre el Mediterráneo occidental y oriental parece ser debida, más al menor número de investigaciones llevados a cabo en el Mediterráneo oriental, que no a unas determinadas pautas en la distribución y abundancia dicha ictiofauna.

Three deep-sea areas in the Mediterranean Sea were sampled using a bottom otter trawl during the DESEAS oceanographic survey carried out from early June to early July 2001, covering an area in the western Mediterranean from 600 to 2800 m in depth and two areas in the central Mediterranean, the western and eastern Ionian Sea from 600 to 4000 m in depth. Decapod crustaceans were one of the dominant megafaunal groups, together with fishes, in terms of both biomass and abundance. A total of 2799 decapod specimens belonging to 32 species were collected. Abundance and biomass of the decapod crustaceans decreased with depth. For depths below 1000 m, a decrease in total decapod biomass was recorded from west to east. From the data reported in this study and data from the available literature, decapod crustaceans display differential depth distributions in the different areas. For the most abundant species, size and sex distributions versus depth gradient were examined to compare intraspecific population structures between the sampling areas. Despite differences, among areas, in the species biomass compositions by depth strata and differences in their overall bathymetric ranges of distribution, intraspecific population structures of the most abundant species seem to follow similar trends for size and sex distribution versus depth gradient between the western and central areas. This might be an indication that the individual species structure their populations according to a similar basic pattern regardless of differences in local environmental features. The results have been discussed in the general context of the environmental features encountered by the species in each of the sampling areas., Se muestrearon tres áreas del Mediterráneo profundo con una red de arrastre bentónica durante la campaña oceanográfica DESEAS, desde principios de junio hasta principios de julio de 2001. El rango batimétrico muestreado en el Mediterráneo occidental fue entre los 600 y los 2800 m de profundidad. Se muestraron dos áreas del Mediterráneo central, una situada en la parte occidental del Mar Iónico y la otra situada en la parte más oriental del mismo, cubriendo un rango batimétrico entre los 600 y 4000 m de profundidad. Los crustáceos decápodos fueron uno de los grupos, junto con los peces, dominantes de la megafauna en términos de biomasa y abundancia. Se capturaron en total de 2799 individuos de decápodos pertenecientes a 32 especies. La abundancia y biomasa de los crústaceos decápodos disminuyó con la profundiad. Teniendo en cuenta únicamente las muestras tomadas a profundidades superiores a los 100 m, se detectó una disminución de la biomasa total de los crustáceos decápodos en el área de muestreo más oriental (parte oriental del mar Jónico con respecto al mediterráneo occidental (mar Balear). Los datos aportados en este estudio junto con los datos disponibles en la literatura, indican que los cruatáceos decápodos se distribuyen en rangos batimétricos diferentes en cada una de las áreas de estudio. Aunque se encontraron diferencias entre las áreas de estudio, en la distribución de biomasa con respecto a la profundidad y en los rangos batimétricos de cada especie, la estructura de población de las especies mas abundantes para seguir la msima tendencia por lo que respecta a la distribución batimétrica de sexos y tamaño de sus individuos en toda el área geográfica muestreada. Este último aspecto podría ser una indicación de que las especies estructuran sus poblaciones de acuerdo a un patrón similar, independientemente de las diferencias locales del ambiente. Los resultados se han discutido bajo el contexto general de las características ambientales encontradas por cada especie en cada una de las áreas de muestreo.

[EN] The object of the DESEAS Project, funded by the EC, was to gather preliminary data on the abundance and maximum depth distribution of the rose shrimp Aristeusantennatus in the Mediterranean Sea. An exploratory survey was therefore designed with that goal in mind and conducted on the R/V García del Cid, sampling the maximum depths in three specific areas in the central and western Mediterranean, one off Ibiza (Balearic Islands), one off Calabria (western Ionian Sea), and one off the southern Peloponnesian Peninsula (Gulf of Kalamata, eastern Ionian Sea). The depths sampled ranged from 600 to 4000 m, with specimens of A. antennatus being collected down to 3300 m. There were three distinct boundaries marking the abundance of this species: < 1000 m, relatively high abundance (up to 1000 ind km-2); 1000-1500 m, relatively moderate abundance (up to 300 ind km-2); and > 1500 m, relatively low abundance (, [ES] El objetivo del proyecto DESEAS, financiado por la CE, fue obtener datos preliminares de abundancia y distribución de profundidad máxima de la gamba rosada Aristeus antennatus en el Mar Mediterráneo. El diseño de la campaña exploratoria fue realizado con este propósito y se desarrolló a bordo del B/O García del Cid. Se realizaron muestreos en las máximas profundidades de tres áreas específicas en el Mediterráneo occidental y central: una cerca de Menorca (Islas Baleares), otra frente a las costas de Calabria (Iónico occidental) y la última al sur de la península del Peloponeso (en el Golfo de Kalamata, Iónico oriental). Las profundidades muestreadas fueron las comprendidas entre 600 y 4000 m, obteniendo individuos de A. antennatus hasta 3300 m. Se detectaron tres niveles de abundancias diferenciados en esta especie: < 1000 m, relativamente muy abundante (hasta 1000 ind km-2); 1000-1500 m, abundancia relativamente moderada (hasta 300 ind km-2); > 1500 m, relativamente poco abundante (< 100 ind km-2). En las tres áreas estudiadas se confirmó la estructura de la población conocida hasta el momento, es decir, aumento de la proporción de machos y juveniles con la profundidad. No se encontraron evidencias de diferencias en el desarrollo gonadal o en la presencia de espermatóforos de las hembras entre áreas. Finalmente se observó la existencia de una tendencia en el aumento de la proporción de juveniles con la profundidad, This work was financially supported by the Directorate General Fisheries of the EC as part of the DESEAS survey programme (DGXIV, Study Contract, 2000/39)

The application of statistical models on a time series of data arising from the MEDITS International Trawl Survey, an experimental demersal resources survey carried out during six years (1994-1999) in the same season of the year (late spring - early summer) using the same fishing gear in a large part of the Mediterranean, has allowed for a study to compare, for the first time, the space-time distribution, abundance, and size structure of the two Aristeids Aristaeomorpha foliacea and Aristeus antennatus throughout most of the Mediterranean Sea. This research has shown a large variability among the six reference areas, that were arbitrarily defined within the basin. In particular the two shrimps do not seem to present any correlation or yield continuity in the years. The same lack of homogeneity was also observed in the time trend of the abundances and frequencies of each of the two species. These data seem to confirm the intrinsic variability of the species, the cause of which is still unknown and undocumented. Nevertheless, a longitudinal gradient of catches has been observed where A. antennatus is more abundant in the west and A. foliacea in the east of the basin., No disponible

Data on the distribution and biology of the deep-sea portunid crab Bathynectes maravigna are reported for the Mediterranean Sea, based on several fisheries research surveys. Densities are low and, therefore, biological data are scarce. In the western Mediterranean, the species is much commoner in Alborán Sea than in the Catalano-Balearic Sea. Occurrences are also scarce in the southern Adriatic and northwestern Thyrrenian Sea, as well as in the Ionian Sea. The Alborán Sea and the seas surrounding the southern Italian peninsula are the areas where densities are the highest. The occurrence depth range was found to be 245–786 m, but most of the occurrences took place deeper than 500 m. Sizes ranged between 9 and 51 mm carapace length in males and between 12 and 51 mm in females. Ovigerous females have been only reported in October–December and March–May. Eighty three percent of both males and females are right-handed. Sexual dimorphism was present in cheliped length with males having longer chelae than females. The species appears to be much commoner in those areas where Atlantic influence is the highest, We wish to thank all participants in the EU MEDITS trawl surveys for their help and collaboration in the acquisition of the data

The occurrence of Brachioteuthis riisei and Onychoteuthis banksi in the region of Argosaronikos (Aegean Sea) is reported in this note. Both species were collected by the experimental bottom trawl net used in the framework of the International Bottom Trawl Survey in the Mediterranean (MEDITS). A single individual of Brachioteuthis riisei was caught in June 1997, between 380-418 m of depth. It was a fully mature female with a mantle length of 66 mm, representing the largest individual ever caught in the Mediterranean and the first one recorded in the Aegean Sea. Five specimens of Onychoteuthis banksi were found in June 1997 and June 1998 at depths ranging between 685 and 760 m. All specimens were immature their size ranging from 55 to 107 mm DML. This is the first finding of the species in the Aegean Sea and the Eastern Mediterranean (east of 23¡ E).

The trawl codend selectivity on Nephrops norvegicus was studied using diamond meshes of 16 mm, 20 mm, 24 mm and 26 mm nominal side mesh size. The cover codend method was applied for the sampling. The logistic function for the probability of retention by the codend was used for the estimation of selectivity parameters from all data combined. The results indicated that the 16 mm mesh size was not selective and that almost all individuals were retained. The 24 mm and 26 mm mesh size showed quite similar results and were a little more selective than the 20 mm mesh size. None of the experimental mesh sizes proved to be adequate for N. norvegicus, since all estimated values of length of 50% retention (L50) were lower than the length at first maturity and those of length of 25% retention (L25) were lower than the legislated minimum landing size. It is suggested that mesh size should be much larger than 20 mm, the size legislated by E.U. for the Mediterranean., La selectividad de Nephrops norvegicus para el copo de arrastre se ha analizado utilizando mallas de 16 mm, 20 mm, 24 mm and 26 mm (de lado). Para el estudio de la selectividad se utilizó el método del sobrecopo. Se utilizó la ecuación logística para conocer la probabilidad de retención del copo y los parámetros de selectividad. Los resultados indican que la malla de 16 mm no es selectiva y que no deja escapar casi ningún ejemplar. Las mallas de 24 mm y de 26 mm presentan resultados parecidos entre sí y son un poco más selectivas que la malla de 20 mm. Aunque la proporción de individuos retenidos aumenta con la luz de malla, ninguna de las mallas utilizadas se considera adecuada para N. norvegicus, ya que todos los valores estimados de L50 fueron menores que la talla de primera madurez y, que todos los valores de L25 fueron menores que la talla mínima de captura legislada. Se recomienda que la malla del copo debe ser mucho más que 20 mm, la cual es la malla legislada por la EU para el Mediterráneo.