Mapping Deep-Sea Features in UK Waters For Use in Marine Protected Area Network Design

Full version unavailable due to 3rd party copyright restrictionsWith an increase in demand on deep-sea resources comes a need for appropriate and effective management of this ecosystem. The establishment of a representative network of deep-sea Marine Protected Areas offers one tool with which to address the conservation needs of the deep sea. While a number of deep-sea habitats have been identified as vulnerable to anthropogenic activities (e.g. cold-water coral reefs and sponge aggregations), poor knowledge of the distribution of these habitats hinders conservation efforts and network planning, and thus we need habitat maps. With improvements in acoustic data resolution acquired from the deep sea, and the ability to cover large areas rapidly, the use of acoustic techniques in mapping biological habitats is growing. Multibeam bathymetry and its derived terrain variables can potentially provide important information that can aid in the delineation and characterisation of biological communities. A necessary prelude to mapping is therefore the definition of biological assemblages for use as mapping units. Two megahabitat features (seamount and submarine canyons) were sampled using acoustic and ground-truthing to characterise and map the distribution of benthic assemblages. Species were identified as distinct morpho-types and catalogued, and still images quantitatively analysed. Standard multivariate community analysis was undertaken to define distinct faunal assemblage that may act as mapping units. Those clusters identified by the SIMPROF routine were taken against a set of criteria to reject/accept as robust assemblages that may be used as mapping units. Twenty two benthic assemblages or biotopes were defined from multivariate analysis of quantitative species data, 11 from the SW Approaches and 11 from Anton Dohrn Seamount, and a further one from video observations (SW Approaches). Taken against current definitions, 11 of these were considered as Vulnerable Marine Ecosystems (VME). Diversity was measured to compliment the comprehensive description of biotopes. The use of multivariate diversity indices proved better for comparing diversity of biotopes as it captures a more than one aspect of diversity of the community. Two biotopes were common to both megahabitat features, cold-water coral reef habitats, and those from Anton Dohrn Seamount were more diverse than from the SW Approaches. Modelling techniques were employed to test the relationship between biotopes and environmental and geophysical parameters, which may be used as surrogates to map VME. Generalised Additive Models of Vulnerable Marine Ecosystems revealed multibeam bathymetry and its derived parameters to be significant surrogate for mapping the distribution of some assemblages, particularly those that appear to be influenced by current regime; whilst not so well for those whose distribution is not so strongly current driven e.g. soft sediment communities. In terms of deep-sea mapping, the use of multibeam can prove a useful mapping tool if the resolution of the data is at an appropriate scale that will identify meso-scale geomorphological features, such as cliff-top mounds, that may act as proxies for occurrence of biotopes, but this relationship is still unclear. Surrogates were used to map VME across the seamount and submarine canyons, and full coverage maps were produced for all biotopes occurring on these megahabitat features.Joint Nature Conservation Committe

Distribution and abundance of molluscs and decapod crustaceans in trawl samples from the Galician Shelf (NW Spain)

Versión del editor

Agrupaciones megafaunales del mar profundo del talud norte español en relación a factores ambientales

Four deep sea fish and invertebrate assemblages from the northern Spanish slope were identified and related to geographic and bathymetric factors. The Peñas Cape comprises a boundary area splitting the more productive, wider and sandy western shelf from the less productive, narrow and muddy eastern part. The four faunal assemblages described were a shelf-slope transition assemblage (SST, 400-500 m); two upper slope assemblages (500-650 m), one corresponding to the western area of Cape Peñas and one to the eastern area; and a middle slope assemblage (650-750 m). The SST was dominated by plankton-feeding fish and was hence less diverse than the other strata. This dominance was more evident west of the Peñas Cape, where upwelling was stronger. Regarding invertebrates, plankton-feeding fish and benthos-feeding invertebrates dominated the SST, whereas zooplankton-feeding and deposit-feeding invertebrates dominated the middle slope. The western assemblages were richer in species as a consequence of a more complex food web, especially of guilds related to water column production: plankton-feeding fish and filter- and zooplankton-feeding invertebrates.Se han identificado cuatro agrupaciones de peces e invertebrados en el talud norte español, relacionados con factores geográficos y batimétricos. Cabo Peñas representa una frontera que separa la plataforma occidental, más productiva, ancha y arenosa, de la oriental, menos productiva, más estrecha y de fondos fangosos. Las agrupaciones faunísticas descritas son: una agrupación de transición plataforma-talud (SST, 400-500 m), dos agrupaciones del talud superior (500-650 m), una correspondiendo con la zona occidental de Cabo Peñas (USW) y la otra con la zona oriental respecto al cabo (USE), y una agrupación del talud medio (MS, 650-750 m). La agrupación SST está dominada por peces planctófagos y presenta por ello menor diversidad que otros estratos. Esta dominancia es mayor al oeste de Cabo Peñas, donde los procesos de afloramiento son más fuertes. Respecto a los invertebrados, las especies bentófagas dominan en la agrupaciones SST, mientras que los depositívoros dominan en el talud medio. Las agrupaciones situadas al oeste presentan una mayor riqueza específica, como consecuencia de una red trófica más compleja, especialmente de grupos tróficos relacionados con la producción de la columna de agua: peces planctófagos e invertebrados filtradores o zooplanctófagos

Agregaciones de pennatuláceos en la plataforma del norte de España: distribución y agrupaciones faunísticas

The sea pens Funiculina quadrangularis, Pennatula aculeata, Pennatula phosphorea, Pteroeides spinosum and Veretillum cynomorium are known to be characteristic species of the habitat ‘pennatulacean communities on circalittoral and upper bathyal soft bottoms’, described recently on the northern Atlantic Spanish shelf under the terms of the EU directives. Distribution, abundance and environmental data collected from 1995 to 2010 in the Northern Spanish Shelf Groundfish Surveys in the Cantabrian Sea and off Galicia (SPNGFS) were analysed. Although low densities of sea pens were commonly found over the years, some aggregations were shown. Multivariate analysis separated the aggregations of F. quadrangularis and of Pennatula spp. found on circalittoral soft bottoms. In addition, evidence of aggregations of F. quadrangularis on upper bathyal sites was also found. Depth and longitude, which were closely related to organic matter and sediment particle size, were key factors in determining the distribution and abundance of these aggregations. However, very little information on distribution and density of the species P. spinosum and V. cynomorium was obtained. Details of community composition of F. quadrangularis and Pennatula spp. were studied and compared with those of the OSPAR habitat “sea pen and burrowing megafauna communities” in other areas. The results improve our knowledge concerning sea pen communities in the southern Bay of Biscay and contribute to a global assessment of the status of these communities in the northeast Atlantic.Los pennatuláceos Funiculina quadrangularis, Pennatula aculeata, Pennatula phosphorea, Pteroeides spinosum y Veretillum cynomorium son especies características del hábitat “comunidades de pennatuláceos sobre fondos blandos profundos y circalitorales” descrito recientemente en la plataforma noratlántica española bajo directrices europeas. Datos de distribución, abundancia y ambientales recogidos desde 1995 hasta 2010 en las campañas demersales de la plataforma del norte de España y Galicia (SPNGFS) han sido analizados. Aunque predominan las bajas densidades de pennatuláceos a lo largo de los años, se han encontrado agregaciones. El análisis multivariante ha separado las agregaciones encontradas de F. quadrangularis y Pennatula spp. en los fondos blandos circalitorales. Además, se han encontrado agregaciones de F. quadrangularis en los fondos blandos profundos. La profundidad y la longitud, estrechamente relacionadas con el contenido de materia orgánica y el tamaño de partícula del sedimento, han sido los factores clave en la distribución y abundancia de estas agregaciones. Sin embargo, se ha obtenido poca información de la distribución y densidad de las especies P. spinosum y V. cynomorium. Se ha estudiado la composición de las comunidades de F. quadrangularis y Pennatula spp. y se ha comparado con el hábitat definido por OSPAR “sea pen and burrowing megafauna communities” en otras áreas. Los resultados mejoran el conocimiento de las comunidades de pennatuláceos en el sur del Golfo de Vizcaya y ayudan en la evaluación global del estatus de estas comunidades en el noreste Atlántico

Estudios experimentales de la ecología alimentaria de Munida subrugosa (White, 1847) (Decapoda: Anomura; Galatheidae) de la Región de Magallanes, sur de Chile

Feeding behaviour and food uptake rates of the anomuran crab Munida subrugosa from the southern Magellan region (Chile) were studied under laboratory conditions. Crabs exhibited a marked preference for meat versus macroalgae, with uptake rates being 14 times higher. Different algal species were ranked according to structure and detrital cover. Observations suggest that scavenging and cannibalism, restricted to injured or moulting individuals, are regularly applied in the natural habitat, whereas active hunting is only performed on suitable prey. The main food resource is suggested to be of microscopic origin, given the time spent on typical food uptake movements for detritus and suspended food. The findings of this study, backed up by results of simultaneously carried out stomach analysis, proved M. subrugosa to be an opportunistic feeder that can make use of different forms of food uptake.Se estudiaron los hábitos alimentarios y tasas de ingesta de alimento del crustáceo anomuro Munida subrugosa en la Región de Magallanes (Chile) bajo condiciones de laboratorio. Los cangrejos mostraron una marcada preferencia por la carne versus las macroalgas, con tasas de ingesta 14 veces más altas. Diversas especies de algas fueron clasificadas en función de la estructura y la capa detrítica. Las observaciones señalan que la alimentación sobre carroña y el canibalismo (restringido al consumo de individuos dañados o en estado de muda) constituyen una estrategia aplicada frecuentemente en el hábitat natural. Sin embargo, se sugiere que la principal fuente de alimento es de origen microscópico, dada la conducta alimenticia observada en ejemplares vivos, que se alimentan de material particulado y en suspensión. Los resultados de este estudio, apoyado por los resultados de análisis de contenidos estomacales realizados simultáneamente, demuestran que Munida subrugosa es un predador oportunista, que puede hacer uso de diferentes formas de obtención de alimento