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Exposed sandy beaches are widespread coastal habitats with temporal and spatial variability. O Rostro beach (Galicia, north-west Spain) was the most severely affected beach in the ‘Prestige’ oil spill (November 2002). Monitoring sampling was conducted to study macroinfaunal composition and structure after the oil spill episode. The purpose of this survey was to characterize macroinfaunal variations on the beach over a yearly scale (2003–2007) and determine the recovery period. These data are compared with the only available data collected before the spill (1995). Two zones where identified with different recovery trends: (1) supralittoral, occupied either by talitrid amphipods, oniscoidean isopods and insects; and (2) intertidal, where marine crustaceans prevailed. Beach morphodynamics partially buried the oil, which gradually reappeared and was dragged to the coast. Negative ecological effects were observed in the short term (six months after the 2002 spill) but macroinfauna apparently recovered in the following years (2004–2007), showing that macroinfaunal assemblages of this beach are resilient enough to recover after severe stress.

The suprabenthos is considered a major food resource for some fish and birds. Moreover, it plays a key role in the food chain and in nutrient regeneration in the surf zone. The aim of this study was to determine the factors that regulate this fauna and the differences between the suprabenthic groups, to study the possibility of seasonal variations and to compare these results with those of other studies conducted in Europe. A study and geographical comparison was conducted of the temporal patterns of the suprabenthos in the swash zone at two sandy beaches on the NE Atlantic coast (Altar and Ladeira beaches) in the NW of Spain. The study was carried out from September 2005 to August 2007 (24 months). To study the fauna, 60 m 2 was sampled monthly with a suprabenthic sledge, and a total of 101 species belonging to Peracarida and Decapoda were recorded. Total densities ranged from 0.42 ind·m − 2 to 178.75 ind·m − 2 . Ladeira beach showed higher densities and species richness than Altar beach, and the biocoenosis showed a different dynamic over the 24 months and between years and locations. These results indicate that there is no clear seasonality in the dynamic of suprabenthic species, although the variance of Peracarida orders was explained in diverse degree by environmental variables. The environmental models implemented explained between 27.7% and 93.8% of the faunal data, and hydrodynamic factors and daily global irradiance were selected as the best factors to explain the temporal variations.

The exposed sandy beach of Ladeira (Corrubedo Bay, NW Spain) was sampledduring seven years (2003-2009) after the Prestige oil spill(winter 2002-03), todetermine interannual variations in the macroinfaunal community in two ways:(i) through ecological indices (species richness and abundances, Shannon'sdiversityand Pielou's evenness) and (ii) through the density of the most representativespecies. A clear zonation pattern was found, consisting of two zones:(i) the supralittoral, occupied by talitrid amphipods, isopods and insects,and(ii) the intertidal, where marine crustaceans and polychaetes prevailed. Theamphipods Talitrus saltator and Talorchestia deshayesiidominated from the driftline upwards, and isopods (Eurydice spp.), polychaetes (Scolelepisspp.) andthe amphipod Pontocrates arenarius dominated the intertidal. Univariateindices remained constant throughout the study period in the supralittoral,but they varied widely in the intertidal zone. Multivariate analysis showedthat the Prestige oil spill scarcely affected the macroinfaunalcommunity structure during the study period (2003-2009) and its effect waslimited just to the first campaign (2003), six months after the Prestigeaccident.

Eighteen sandy beaches were sampled along the 1659 km of the Galician coast (NW Spain) six months after the Prestige oil-spill to study the impact of the fuel and the clean-up activities on the macroinfauna community. A transect was extended at each beach, from above the drift line to below the swash line at five sampled levels; at each level six 0.05 m2 replicates were taken to a depth of 30 cm and sieved through a 1mm mesh, and the organisms collected and preserved. Results were compared with previous data obtained using the same procedures. The macroinfauna was numerically dominated by the amphipod Pontocrates arenarius, the isopod genus Eurydice, the polychaete Scolelepis squamata, and the amphipod Talitrus saltator. As a result of the Prestige oil-spill and the clean-up activities, beach populations were reduced, with Eurydice and S. squamata as the most affected taxa.

The community structure of the macrobenthic (>1 mm) fauna of an intertidal soft-bottom estuary, the Ria de Foz (Galicia, Northwest Spain) was investigated on 99 occasions during June, September and December 1984 and March 1985. The infaunal data were subjected to classification and ordination techniques. The analyses indicated that sediment characteristics (grain size, percentage silt-clay and organic-matter content) and tidal height are the most important factors governing the distribution and abundance of the intertidal communities. Three faunal assemblages were identified and examined in terms of species dominance, constancy and fidelity. In the clean sands of the outer estuary two main assemblages were distinguished; one, corresponding to the “boreal LusitanianTellina community”, inhabited the middle and lower tidal levels; the other, typical of a biocoenosis of sands and slightly muddy mediolittoral sands, inhabited the upper tidal level. The third benthic assemblage occupied the muddy sands and mud of the inner estuary and displayed some features in common with theCardium edule-Scrobicularia community described by Thorson.