Determining and mapping species sensitivity to trawling impacts: the BEnthos Sensitivity Index to Trawling Operations (BESITO)

Applying an ecosystem approach requires a deep and holistic understanding of interactions between human activities and ecosystems. Bottom trawling is the most widespread physical human disturbance in the seabed and produces a wide range of direct and indirect impacts on benthic ecosystems. In this work, we develop a new index, the BEnthos Sensitivity Index to Trawling Operations (BESITO), using biological traits to classify species according to their sensitivity to bottom trawling. Seventy-nine different benthic taxa were classified according to their BESITO scores in three groups. The effect of trawling on the relative abundance of each group (measured as biomass proportion) was analysed using General Additive Models (GAMs) in a distribution model framework. The distribution of the relative biomass of each group was mapped and the impact of trawling was computed. Species with the lowest BESITO score (group I) showed a positive response to trawling disturbance (opportunistic response) whereas species with values higher than 2 (group III) showed a negative response (sensitive response). Species with a BESITO score of 2 did not show a significant response to the pressure (tolerant response). Trawling disturbance reduced relative biomass of sensitive species by 31% across the study area. This value increased to 46% when shelf-break was considered in isolation and reached values of 59.6% in the most impacted habitat (deep-sea muddy sands). The new index classified successfully the analysed species according to their sensitivity to trawling allowing modeling the impact of trawling disturbance on sensitive species, without the masking effect of opposed responses

Spatial assessment of benthic habitats vulnerability to bottom fishing in a Mediterranean seamount

Physical damage caused by the mechanical impact of bottom fishing gears on epibenthic community can reduce the biomass and coverage of habitat-forming species as well as the richness and diversity of the rest of the associated community. A practical development of a methodology for spatially assessing the potential degree of disturbance that benthic habitats suffered as a consequence of trawling and long-lining was carried out using a seamount located within a marine Natura 2000 site in the western Mediterranean as a case of study. By jointly assessing the extent of the impact and mapping the sensitivity of all the habitats to these fishing activities, vulnerability and disturbance per benthic habitat and pressure type was evaluated. Habitat sensitivity and fishing effort were combined using a disturbance matrix which categorize grid cells in 9 different levels of disturbance. Additionally, different thresholds of probability of presence of the different habitats obtained from distribution models were used to identify priority conservation and potential recovery. Around 50% of the area was disturbed by fishing and all habitats, both biogenic and non-biogenic, were subjected to fishing. Most of the trawling effort was carried out on soft bathyal substrates while the percentage of longlining effort carried out on hard bottoms was relatively higher than for trawling. Biogenic habitats showed significantly greater sensitivity to both trawling and longlining than non-biogenic habitats. Disturbed, priority conservation and potential recovery areas were identified and mapped in order to inform marine spatial planning.En prensa1,86

Living at the top. Connectivity limitations and summit depth drive fish diversity patterns in an isolated seamount

The fish assemblages of the Galicia Bank and the closest continental slope (northwest of Spain) were analysed using otter trawls to improve our understanding of how environmental drivers structure seamount fish communities in the deep sea. The effect of environmental drivers on these assemblages was studied using multivariate techniques together with the variation in α and β diversity across assemblages. Fish fauna in the study area was distributed in 5 different assemblages generated by the action of 3 main drivers: depth, distance to the coast and presence of cold-water corals. The observed differences in species composition among assemblages were mostly explained by species turnover across a depth gradient. The seamount summit and the continental slope showed important differences despite sharing similar depths, mainly because several species requiring shallow juvenile habitats were absent from the summit. These absences were observed in both summit assemblages inside and outside the cold-water coral reef. Our results show that in isolated seamounts with relatively deep summits, the lack of connectivity with shallower areas limits the presence of certain species, probably due to the impossibility for these species to migrate directly from shallow to deeper seabed areas. These species are replaced by species with preferences for deeper habitats, providing the fish assemblages located at the top of the summit with a deeper profile than observed in fish assemblages of the continental slope.En prensa2,48

Proposed approaches for indicator integration. ECAPRHA Deliverable Wp 4.1

<p>Cross-tabulation of cough and the modified Valsalva maneuver (m-VM) for determining the degree of right-to-left shunt.</p

Benthic Fauna of Littoral and Deep-Sea Habitats of the Alboran Sea: A Hotspot of Biodiversity

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Diagnostico del Impacto del Palangre de Fondo en los Hábitats Bentónicos en los LICs de la RN20000

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Documentación de arrecifes de corales de agua fría en el Mediterráneo occidental (Mar de Alborán).

La presencia de arrecifes de corales de agua fría, principalmente Lophelia pertusa y Madrepora oculata en el Mar Mediterráneo en general y en el Mar de Alborán en particular es conocida, sin embargo, los estudios sobre estos hábitats son escasos y su distribución es incompleta. Oceana ha muestreado el mar de Alborán desde 2005 con la ayuda un Vehículo de Observación Remota (ROV) documentando la presencia de arrecifes de coral de estas especies. Como resultado se han documentado algunas colonias conocidas, principalmente por estudios geológicos, pero también se han filmado nuevos arrecifes como el de Cabliers. Parte de estos arrecifes están muertos y sobre ellos se desarrollan colonias vivas de estas especies, en ocasiones de hasta 1m de altura, los datos publicados pretenden contribuir al conocimiento de estas especies, su distribución y los habitas que generan, para favorecer de este modo su gestión y conservación

Sponge grounds of Artemisina (Porifera, Demospongiae) in the Iberian Peninsula, ecological characterization by ROV techniques

Artemisina Vosmaer, 1885 is a poecilosclerid microcionoid sponge genus with 20 valid species, seven of which have been recorded in the Atlantic Ocean. The present study describes Artemisina sponge grounds in Iberia Peninsula. A. transiens is a sponge described in 1890 by Topsent in Galicia (Spain); A. hispanica was also collected in the north of Spain by Ferrer-Hernández (1917); World Porifera Database (WPD) considers at the moment both mushroom-shaped species as synonyms (van Soest et al., 2018), but we have only been able to check the types of A. hispanica. The studied samples were collected in Somos Llungo station and they correspond clearly to those described as A. hispanica by Ferrer-Hernández (1917) and it presents differences in the skeleton with respet to description of A. transiens in the literture. There are no more records after 1917 and there are no data of ecological characterisation nor is there a detailed description of its skeletal composition with Scanning Electron Microscopy. In the previous records the formation of sponge grounds of these species was not known. Oceana, the largest international organization focused solely on protecting the world’s oceans, has recorded the habitat of Artemisina in Atlantic and Cantabrian waters during a series of ROV cruises for the identification of marine areas with high ecological value that need protection. Its life conditions and associated fauna are described from direct observations for the first time