Ampelisca lusitanica (Crustacea: Amphipoda): new species for the Atlantic coast of Morocco

Background This study reports for the first time the presence of the Lusitanian ampeliscid amphipod Ampelisca lusitanica Bellan-Santini & Marques, 1986 in the northwestern Atlantic coast of Morocco. Methods Specimens were collected in January 2015 from intertidal rock pools along the El Jadida shoreline associated with the brown algae Bifurcaria bifurcata and Sargassum muticum. Results Systematic description of the species is presented, as well as a discussion of its ecological and geographical distribution. Conclusion This new finding extends the geographical distribution from the Lusitanian (Europe) to the Mauritanian (Africa) region and increases knowledge of the ecology and the global distribution of A. lusitanica found, previously, only on Portuguese and Spanish coasts.info:eu-repo/semantics/publishedVersio

La préservation du patrimoine naturel littoral dans le processus de la gestion intégrée des zones côtières : éléments de réflexion pour l'élaboration d'un projet et perspectives

The coastal zone is an area of conflicting processes reflecting its position at the interface between the terrestrial and marine environments. This area needs further study and an enforcement of co-ordinated conservation policy for the implementation of effective protection. A multidisciplinary team (law, ecology, biology, and geography) has published a book, which assembles the elements of current politics involved with the preservation of the natural heritage of the coasts of mainland France. Part 1 deals on the definition of the coastal zone, the dispositions for the preservation of the natural heritage, the institutions concerned with its knowledge about and management and the objective criteria and methods for the choice or separation of zones to be protected. Part 2 gives the characteristic heritage aspects of the three coastal chosen regions. Part 3 gives perspectives to set up a more management model for the preservation of the natural heritage. It is necessary to have a clarification of current expertise resulting in a harmonization and institutional co-ordination of organisms linked to the coastal zone. The reform of the status of the CELRL increases its intervention in the maritime public domain. It offers prospects to consolidate this organization in its role in the protection of the littoral natural patrimonyInterface entre le milieu terrestre et le milieu marin, le littoral est une zone conflictuelle où les usages sont contradictoires, et un espace où il existe des besoins de connaissances et où il faut mettre en place une politique coordonnée de protection. Un ouvrage vient d'être réalisé par une équipe pluridisciplinaire (droit, écologie, biologie, géographie) en réponse au programme LITEAU du MATE. Il recense les éléments de la politique de préservation du patrimoine naturel de la France métropolitaine. Il prend pour exemples trois littoraux. Le Temps 1 s'ordonne autour des définitions du littoral, des institutions impliquées dans sa connaissance et sa gestion, des critères et méthodes objectives pour choisir ou délimiter des zones à préserver. Le Temps 2 traite des particularités patrimoniales des trois régions choisies. Le Temps 3 donne des perspectives pour construire un modèle de gestion satisfaisant du patrimoine naturel littoral à partir de l'analyse de l'existant. Les nombreuses interactions entre les intervenants multiples sur le littoral imposent une clarification des compétences, une harmonisation et une coordination institutionnelle. La réforme du statut du CELRL prévoit son intervention au domaine public maritime ; elle offre des perspectives pour le conforter dans son rôle d'acteur de la protection du patrimoine naturel littoral

Wanted dead or alive : high diversity of macroinvertebrates associated with living and ’dead’ Posidonia oceanica matte

The Mediterranean endemic seagrass Posidonia oceanica forms beds characterised by a dense leaf canopy and a thick root-rhizome ‘matte’. Death of P. oceanica shoots leads to exposure of the underlying matte, which can persist for many years, and is termed ‘dead’ matte. Traditionally, dead matte has been regarded as a degraded habitat. To test whether this assumption was true, the motile macroinvertebrates of adjacent living (with shoots) and dead (without shoots) matte of P. oceanica were sampled in four different plots located at the same depth (5–6 m) in Mellieha Bay, Malta (central Mediterranean). The total number of species and abundance were significantly higher (ANOVA; P<0.05 and P<0.01, respectively) in the dead matte than in living P. oceanica matte, despite the presence of the foliar canopy in the latter. Multivariate analysis (MDS) clearly showed two main groups of assemblages, corresponding to the two matte types. The amphipods Leptocheirus guttatus and Maera grossimana, and the polychaete Nereis rava contributed most to the dissimilarity between the two different matte types. Several unique properties of the dead matte contributing to the unexpected higher number of species and abundance of motile macroinvertebrates associated with this habitat are discussed. The findings have important implications for the conservation of bare P. oceanica matte, which has been generally viewed as a habitat of low ecological value.peer-reviewe

Environmental drivers of distribution and reef development of the Mediterranean coral Cladocora caespitosa

Cladocora caespitosa is the only Mediterranean scleractinian similar to tropical reef-building corals. While this species is part of the recent fossil history of the Mediterranean Sea, it is currently considered endangered due to its decline during the last decades. Environmental factors affecting the distribution and persistence of extensive bank reefs of this endemic species across its whole geographic range are poorly understood. In this study, we examined the environmental response of C. caespitosa and its main types of assemblages using ecological niche modeling and ordination analysis. We also predicted other suitable areas for the occurrence of the species and assessed the conservation effectiveness of Mediterranean marine protected areas (MPAs) for this coral. We found that phosphate concentration and wave height were factors affecting both the occurrence of this versatile species and the distribution of its extensive bioconstructions in the Mediterranean Sea. A set of factors (diffuse attenuation coefficient, calcite and nitrate concentrations, mean wave height, sea surface temperature, and shape of the coast) likely act as environmental barriers preventing the species from expansion to the Atlantic Ocean and the Black Sea. Uncertainties in our large-scale statistical results and departures from previous physiological and ecological studies are also discussed under an integrative perspective. This study reveals that Mediterranean MPAs encompass eight of the ten banks and 16 of the 21 beds of C. caespitosa. Preservation of water clarity by avoiding phosphate discharges may improve the protection of this emblematic species.Spanish Ministry of Economy and Competitiveness [CTM2014-57949-R]info:eu-repo/semantics/publishedVersio

An ecosystem-based approach to assess the status of Mediterranean algae-dominated shallow rocky reefs.

A conceptual model was constructed for the functioning the algae-dominated rocky reef ecosystem of the Mediterranean Sea. The Ecosystem-Based Quality Index (reef-EBQI) is based upon this model. This index meets the objectives of the EU Marine Strategy Framework Directive. It is based upon (i) the weighting of each compartment, according to its importance in the functioning of the ecosystem; (ii) biological parameters assessing the state of each compartment; (iii) the aggregation of these parameters, assessing the quality of the ecosystem functioning, for each site; (iv) and a Confidence Index measuring the reliability of the index, for each site. The reef-EBQI was used at 40 sites in the northwestern Mediterranean. It constitutes an efficient tool, because it is based upon a wide set of functional compartments, rather than upon just a few species; it is easy and inexpensive to implement, robust and not redundant with regard to already existing indices

Environmental effects of a marine fish farm of gilthead seabream (Sparus aurata) in the NW Mediterranean Sea on water column and sediment

This study examined the effects of organic enrichment on water column, sediments and macrofauna caused by a fish farm in the Mediterranean Sea. Samples were collected on four sampling campaigns over a one-year cycle. Significant differences were found in the water column in dissolved oxygen, dissolved inorganic nitrogen, phosphate and total phosphorus concentrations between the fish farm and the control. The increase in the dissolved inorganic nitrogen and phosphate concentrations at the fish farm modified the stoichiometric ratios between nutrients, with silicate acting as limiting nutrient at the fish farm 11% more than at the control. Nevertheless, chlorophyll a concentration in the water column was higher at the control station, probably due to the fouling of the underwater fish farm structures. Significant differences were found in sediment concentrations of organic matter, total phosphorus and redox potential between the fish farm and the control. The Canonical Correlation Analysis indicated that organic matter, total phosphorus, redox potential and% of gravels accounted for 68.9% of the total variance in the species data. Changes were observed in macrofauna, with a decrease in number of species and up to a nine-fold increase in abundance with respect to the control. © 2013 Blackwell Publishing Ltd.We would like to thank the Caja del Mediterraneo (CAM) for a pre-doctoral fellowship fund for this research and Antonio Asuncion Acuigroup Maremar Manager, for the facilities and support in conducting the study. The translation of this paper was funded by the Universidad Politecnica de Valencia, Spain.Morata Higón, T.; Falco Giaccaglia, SL.; Gadea, I.; Sospedra Ciscar, J.; Rodilla Alamá, M. (2013). Environmental effects of a marine fish farm of gilthead seabream (Sparus aurata) in the NW Mediterranean Sea on water column and sediment. Aquaculture Research. 1-16. https://doi.org/10.1111/are.12159S116Aguado F. 2001 Impacto ambiental de los sistemas piscícolas marinos: la acuicultura en jaulas flotantes. Series de química oceanográfica 35 83Aguado-Giménez, F., & García-García, B. (2004). Assessment of some chemical parameters in marine sediments exposed to offshore cage fish farming influence: a pilot study. Aquaculture, 242(1-4), 283-295. doi:10.1016/j.aquaculture.2004.08.035Aksu M. Kocatas A. 2007 Environmental effects of the three fish farms in Izmir Bay (Aegean Sea-Turkey) on water column and sediment 414Asociación Empresarial de Productores de Cultivos Marinos (APROMAR) 2011 La Acuicultura Marina de Peces en España 77Banta, G., Holmer, M., Jensen, M., & Kristensen, E. (1999). Effects of two polychaete worms, Nereis diversicolor and Arenicola marina, on aerobic and anaerobic decomposition in a sandy marine sediment. Aquatic Microbial Ecology, 19, 189-204. doi:10.3354/ame019189Borja, Á., Rodríguez, J. G., Black, K., Bodoy, A., Emblow, C., Fernandes, T. F., … Angel, D. (2009). Assessing the suitability of a range of benthic indices in the evaluation of environmental impact of fin and shellfish aquaculture located in sites across Europe. Aquaculture, 293(3-4), 231-240. doi:10.1016/j.aquaculture.2009.04.037Braeckman, U., Provoost, P., Gribsholt, B., Van Gansbeke, D., Middelburg, J., Soetaert, K., … Vanaverbeke, J. (2010). Role of macrofauna functional traits and density in biogeochemical fluxes and bioturbation. Marine Ecology Progress Series, 399, 173-186. doi:10.3354/meps08336Chou, C. L., Haya, K., Paon, L. A., Burridge, L., & Moffatt, J. D. (2002). Aquaculture-related trace metals in sediments and lobsters and relevance to environmental monitoring program ratings for near-field effects. Marine Pollution Bulletin, 44(11), 1259-1268. doi:10.1016/s0025-326x(02)00219-9Christensen, P., Rysgaard, S., Sloth, N., Dalsgaard, T., & Schwærter, S. (2000). Sediment mineralization, nutrient fluxes, denitrification and dissimilatory nitrate reduction to ammonium in an estuarine fjord with sea cage trout farms. Aquatic Microbial Ecology, 21, 73-84. doi:10.3354/ame021073Chung, I.-K., Kang, Y.-H., Yarish, C., George, P. K., & Lee, J.-A. (2002). Application of Seaweed Cultivation to the Bioremediation of Nutrient-Rich Effluent. ALGAE, 17(3), 187-194. doi:10.4490/algae.2002.17.3.187Cromey, C. J., Nickell, T. D., & Black, K. D. (2002). DEPOMOD—modelling the deposition and biological effects of waste solids from marine cage farms. Aquaculture, 214(1-4), 211-239. doi:10.1016/s0044-8486(02)00368-xCugier, P., Struski, C., Blanchard, M., Mazurié, J., Pouvreau, S., Olivier, F., … Thiébaut, E. (2010). Assessing the role of benthic filter feeders on phytoplankton production in a shellfish farming site: Mont Saint Michel Bay, France. Journal of Marine Systems, 82(1-2), 21-34. doi:10.1016/j.jmarsys.2010.02.013Davies, I. M., McHenery, J. G., & Rae, G. H. (1997). Environmental risk from dissolved ivermectin to marine organisms. Aquaculture, 158(3-4), 263-275. doi:10.1016/s0044-8486(97)00209-3Dean, R. J., Shimmield, T. M., & Black, K. D. (2007). Copper, zinc and cadmium in marine cage fish farm sediments: An extensive survey. Environmental Pollution, 145(1), 84-95. doi:10.1016/j.envpol.2006.03.050Delgado, O., Ruiz, J., Pérez, M., Romero, J., & Ballesteros, E. (1999). Effects of fish farming on seagrass (Posidonia oceanica) in a Mediterranean bay: seagrass decline after organic loading cessation. Oceanologica Acta, 22(1), 109-117. doi:10.1016/s0399-1784(99)80037-1Dell’Anno, A., Mei, M. ., Pusceddu, A., & Danovaro, R. (2002). Assessing the trophic state and eutrophication of coastal marine systems: a new approach based on the biochemical composition of sediment organic matter. Marine Pollution Bulletin, 44(7), 611-622. doi:10.1016/s0025-326x(01)00302-2Ferrón, S., Ortega, T., & Forja, J. M. (2009). Benthic fluxes in a tidal salt marsh creek affected by fish farm activities: Río San Pedro (Bay of Cádiz, SW Spain). Marine Chemistry, 113(1-2), 50-62. doi:10.1016/j.marchem.2008.12.002Garren, M., Smriga, S., & Azam, F. (2008). Gradients of coastal fish farm effluents and their effect on coral reef microbes. Environmental Microbiology, 10(9), 2299-2312. doi:10.1111/j.1462-2920.2008.01654.xHolmer, M., & Kristensen, E. (1992). Impact of marine fish cage farming on metabolism and sulfate reduction of underlying sediments. Marine Ecology Progress Series, 80, 191-201. doi:10.3354/meps080191Holmer, M., Wildish, D., & Hargrave, B. (s. f.). Organic Enrichment from Marine Finfish Aquaculture and Effects on Sediment Biogeochemical Processes. Environmental Effects of Marine Finfish Aquaculture, 181-206. doi:10.1007/b136010Huang, Y., Hsieh, H., Huang, S., Meng, P., Chen, Y., Keshavmurthy, S., … Chen, C. (2011). Nutrient enrichment caused by marine cage culture and its influence on subtropical coral communities in turbid waters. Marine Ecology Progress Series, 423, 83-93. doi:10.3354/meps08944Johansson, O., & Wedborg, M. (1980). The ammonia-ammonium equilibrium in seawater at temperatures between 5 and 25�C. Journal of Solution Chemistry, 9(1), 37-44. doi:10.1007/bf00650135Johansson, D., Juell, J.-E., Oppedal, F., Stiansen, J.-E., & Ruohonen, K. (2007). The influence of the pycnocline and cage resistance on current flow, oxygen flux and swimming behaviour of Atlantic salmon (Salmo salar L.) in production cages. Aquaculture, 265(1-4), 271-287. doi:10.1016/j.aquaculture.2006.12.047Juell, J.-E., & Fosseidengen, J. E. (2004). Use of artificial light to control swimming depth and fish density of Atlantic salmon (Salmo salar) in production cages. Aquaculture, 233(1-4), 269-282. doi:10.1016/j.aquaculture.2003.10.026Justić, D., Rabalais, N. N., Turner, R. E., & Dortch, Q. (1995). Changes in nutrient structure of river-dominated coastal waters: stoichiometric nutrient balance and its consequences. Estuarine, Coastal and Shelf Science, 40(3), 339-356. doi:10.1016/s0272-7714(05)80014-9Karakassis, I., Tsapakis, M., & Hatziyanni, E. (1998). Seasonal variability in sediment profiles beneath fish farm cages in the Mediterranean. Marine Ecology Progress Series, 162, 243-252. doi:10.3354/meps162243Karakassis, I. (2000). Impact of cage farming of fish on the seabed in three Mediterranean coastal areas. ICES Journal of Marine Science, 57(5), 1462-1471. doi:10.1006/jmsc.2000.0925Basaran, A. K., Aksu, M., & Egemen, O. (2009). Impacts of the fish farms on the water column nutrient concentrations and accumulation of heavy metals in the sediments in the eastern Aegean Sea (Turkey). Environmental Monitoring and Assessment, 162(1-4), 439-451. doi:10.1007/s10661-009-0808-xLa Rosa, T., Mirto, S., Favaloro, E., Savona, B., Sarà, G., Danovaro, R., & Mazzola, A. (2002). Impact on the water column biogeochemistry of a Mediterranean mussel and fish farm. Water Research, 36(3), 713-721. doi:10.1016/s0043-1354(01)00274-3Maldonado, M., Carmona, M. C., Echeverría, Y., & Riesgo, A. (2005). The environmental impact of Mediterranean cage fish farms at semi-exposed locations: does it need a re-assessment? Helgoland Marine Research, 59(2), 121-135. doi:10.1007/s10152-004-0211-5Mantzavrakos, E., Kornaros, M., Lyberatos, G., & Kaspiris, P. (2007). Impacts of a marine fish farm in Argolikos Gulf (Greece) on the water column and the sediment. Desalination, 210(1-3), 110-124. doi:10.1016/j.desal.2006.05.037Martins, C. I. M., Galhardo, L., Noble, C., Damsgård, B., Spedicato, M. T., Zupa, W., … Kristiansen, T. (2011). Behavioural indicators of welfare in farmed fish. Fish Physiology and Biochemistry, 38(1), 17-41. doi:10.1007/s10695-011-9518-8Morata, T., Sospedra, J., Falco, S., & Rodilla, M. (2012). Exchange of nutrients and oxygen across the sediment–water interface below a Sparus aurata marine fish farm in the north-western Mediterranean Sea. Journal of Soils and Sediments, 12(10), 1623-1632. doi:10.1007/s11368-012-0581-2Murray L. Bulling M. Mayor D. Sanz-Lázaro C. Paton G. Killham K. Sosal M. 2008 Interactive effects of biodiversity, copper and a chemotherapeutant on marine benthic function Proceedings of the World Conference on Marine Biodiversity (MARBEF) Valencia, SpainNizzoli, D., Bartoli, M., & Viaroli, P. (2007). Oxygen and ammonium dynamics during a farming cycle of the bivalve Tapes philippinarum. Hydrobiologia, 587(1), 25-36. doi:10.1007/s10750-007-0683-9Olivos-Ortiz, A. (2002). Continental runoff of nutrients and their possible influence over stoichiometrical relations (DIN:P:Si) in the Northwest Mediterranean waters. Ciencias Marinas, 28(4), 393-406. doi:10.7773/cm.v28i4.235Olsen L.M. Holmer M. Olsen Y. 2008 Perspectives of nutrient emission from fish aquaculture in coastal waters. Literature review with evaluated state of knowledge 87Oppedal, F., Juell, J.-E., & Johansson, D. (2007). Thermo- and photoregulatory swimming behaviour of caged Atlantic salmon: Implications for photoperiod management and fish welfare. Aquaculture, 265(1-4), 70-81. doi:10.1016/j.aquaculture.2007.01.050Pinedo, S., García, M., Satta, M. P., Torres, M. de, & Ballesteros, E. (2007). Rocky-shore communities as indicators of water quality: A case study in the Northwestern Mediterranean. Marine Pollution Bulletin, 55(1-6), 126-135. doi:10.1016/j.marpolbul.2006.08.044Porrello, S., Tomassetti, P., Manzueto, L., Finoia, M. G., Persia, E., Mercatali, I., & Stipa, P. (2005). The influence of marine cages on the sediment chemistry in the Western Mediterranean Sea. Aquaculture, 249(1-4), 145-158. doi:10.1016/j.aquaculture.2005.02.042Rosenberg, R. (2001). Marine benthic faunal successional stages and related sedimentary activity. Scientia Marina, 65(S2), 107-119. doi:10.3989/scimar.2001.65s2107Sakamaki, T., Nishimura, O., & Sudo, R. (2006). Tidal time-scale variation in nutrient flux across the sediment–water interface of an estuarine tidal flat. Estuarine, Coastal and Shelf Science, 67(4), 653-663. doi:10.1016/j.ecss.2006.01.005Sanz-Lázaro, C., & Marín, A. (2011). Diversity Patterns of Benthic Macrofauna Caused by Marine Fish Farming. Diversity, 3(2), 176-199. doi:10.3390/d3020176Siokou-Frangou, I., Christaki, U., Mazzocchi, M. G., Montresor, M., Ribera d&amp;apos;Alcalá, M., Vaqué, D., & Zingone, A. (2010). Plankton in the open Mediterranean Sea: a review. Biogeosciences, 7(5), 1543-1586. doi:10.5194/bg-7-1543-2010Teasdale, P. R., Minett, A. I., Dixon, K., Lewis, T. W., & Batley, G. E. (1998). Practical improvements for redox potential (EH) measurements and the application of a multiple-electrode redox probe (MERP) for characterising sediment in situ. Analytica Chimica Acta, 367(1-3), 201-213. doi:10.1016/s0003-2670(98)00171-8Vila, M., Garcés, E., Masó, M., & Camp, J. (2001). Is the distribution of the toxic dinoflagellate Alexandrium catenella expanding along the NW Mediterranean coast? Marine Ecology Progress Series, 222, 73-83. doi:10.3354/meps222073Vita, R., & Marin, A. (2007). Environmental impact of capture-based bluefin tuna aquaculture on benthic communities in the western Mediterranean. Aquaculture Research, 38(4), 331-339. doi:10.1111/j.1365-2109.2007.01649.xWajsbrot, N., Gasith, A., Krom, M. D., & Popper, D. M. (1991). Acute toxicity of ammonia to juvenile gilthead seabream Sparus aurata under reduced oxygen levels. Aquaculture, 92, 277-288. doi:10.1016/0044-8486(91)90029-7Wu, R. S. . (2002). Hypoxia: from molecular responses to ecosystem responses. 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Temporal variation in vegetative development of Caulerpa scalpelliformis (Chlorophyta) from Baleia beach, Ilha Grande bay (Rio de janeiro, brazil)

Caulerpa scalpelliformis grows on rocky and sandy bottoms at different depths in Jacuacanga Cove, Ilha Grande Bay, where it can form dense patches. The invasive behavior of this and other species of Caulerpa is well documented in the literature. This study analyzed the variation of the vegetative development of C. scalpelliformis from Baleia Beach (23º01'63''S and 44º14'18''W) in Jacuacanga Cove, from June 2003 to September 2004, including plants from rocky and sandy substrates. Morphometric and dry weight data from the erect and prostrate portions were used. Plants were collected from 20 x 20 cm² plots (n=3), randomly positioned on the rocky boulders (&#8773;1.5 m depth) and on contiguous sandy bottom (&#8773;3.0 m depth). During the study period, C. scalpelliformis occurred on both substrates as a pseudo-perennial species, showing partial loss of the erect portions from winter to spring; the height and dry weight of the erect portions increased from summer to autumn on both substrates. The temporal variation of C. scalpelliformis vegetative development in Baleia Beach was similar to that described for the invasive C. racemosa and C. taxifolia from different geographical regions of the world.Caulerpa scalpelliformis cresce sobre substrato rochoso e arenoso a diferentes profundidades na Enseada de Jacuacanga, Baía da Ilha Grande, onde pode formar bancos densos. O comportamento invasor desta e de outras espécies de Caulerpa é bem documentado na literatura. Este estudo analisou a variação do desenvolvimento vegetativo de C. scalpelliformis da Praia da Baleia (23º01'63''S e 44º14'18''W), Enseada de Jacuacanga, de junho de 2003 a setembro de 2004, considerando plantas do substrato rochoso e do fundo de areia. Dados morfométricos e de peso seco das porções prostrada e ereta foram usados. Plantas foram coletadas em quadrados de 20 cm de lado (n=3), posicionados aleatoriamente sobre o substrato rochoso (profundidade &#8773; 1,5 m) e sobre o substrato arenoso (profundidade &#8773; 3,0 m). Durante o período de estudo, C. scalpelliformis ocorreu nos dois substratos como espécie pseudo-perene, mostrando perda parcial das porções eretas do talo do inverno para a primavera; altura e massa seca das porções eretas mostraram tendência de aumento do verão para o outono nos dois substratos. A variação temporal do desenvolvimento vegetativo de C. scalpelliformis na Praia da Baleia foi similar à descrita para C. racemosa e C. taxifolia, espécies invasoras em diferentes regiões do mundo

The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well

Sea Urchins Predation Facilitates Coral Invasion in a Marine Reserve

Macroalgae is the dominant trophic group on Mediterranean infralittoral rocky bottoms, whereas zooxanthellate corals are extremely rare. However, in recent years, the invasive coral Oculina patagonica appears to be increasing its abundance through unknown means. Here we examine the pattern of variation of this species at a marine reserve between 2002 and 2010 and contribute to the understanding of the mechanisms that allow its current increase. Because indirect interactions between species can play a relevant role in the establishment of species, a parallel assessment of the sea urchin Paracentrotus lividus, the main herbivorous invertebrate in this habitat and thus a key species, was conducted. O. patagonica has shown a 3-fold increase in abundance over the last 8 years and has become the most abundant invertebrate in the shallow waters of the marine reserve, matching some dominant erect macroalgae in abundance. High recruitment played an important role in this increasing coral abundance. The results from this study provide compelling evidence that the increase in sea urchin abundance may be one of the main drivers of the observed increase in coral abundance. Sea urchins overgraze macroalgae and create barren patches in the space-limited macroalgal community that subsequently facilitate coral recruitment. This study indicates that trophic interactions contributed to the success of an invasive coral in the Mediterranean because sea urchins grazing activity indirectly facilitated expansion of the coral. Current coral abundance at the marine reserve has ended the monopolization of algae in rocky infralittoral assemblages, an event that could greatly modify both the underwater seascape and the sources of primary production in the ecosystem