Suchergebnisse

5th International Jellyfish Bloom Symposium, 30 May to 3 June 2016, Barcelona.-- 1 page ; Blooms of the salp Thalia democratica are a recurrent feature in many coastal areas where they have significant ecological and societal impacts. To understand the environmental drivers of those blooms in the Catalan Sea, we conducted 8 sampling surveys of T. democratica populations at contrasting seasonal, temperature and chlorophyll conditions. During each survey we used a drifting buoy to track a salp population which we sampled every 30 minutes during a period of three hours, and determined short term variations in the abundances of the different stages. We built a set of different stage-classified population matrix models, each one representing different assumptions about the influence of temperature and chlorophyll on the different stages. The best model was one where only the females were affected by temperature, while matrix elements for the other stages were fixed. Elasticity analysis indicates that females drive the population dynamics through arrested reproduction at high temperatures. Whether this is a direct influence of temperature, or an indirect effect reflecting low food availability remains to be solved. In contrast to previous ideas, our results suggest that it is the female, and not the asexual oozooid, that is responsible for latency periods in salp populations ; Peer Reviewed

9 pages, 1 figure, 1 table ; Deep-water ecosystems are characterized by relatively low carbonate concentration values and, due to ocean acidification (OA), these habitats might be among the first to be exposed to undersaturated conditions in the forthcoming years. However, until now, very few studies have been conducted to test how cold-water coral (CWC) species react to such changes in the seawater chemistry. The present work aims to investigate the mid-term effect of decreased pH on calcification of the two branching CWC species most widely distributed in the Mediterranean, Lophelia pertusa and Madrepora oculata. No significant effects were observed in the skeletal growth rate, microdensity and porosity of both species after 6 months of exposure. However, while the calcification rate of M. oculata was similar for all colony fragments, a heterogeneous skeletal growth pattern was observed in L. pertusa, the younger nubbins showing higher growth rates than the older ones. A higher energy demand is expected in these young, fast-growing fragments and, therefore, a reduction in calcification might be noticed earlier during long-term exposure to acidified conditions. © 2013 by the authors ; This research was supported by the European Project HERMIONE (grant agreement number 226354), the Spanish Government (MINECO) projects ACDC (CTM2009-08849/MAR) and MANIFEST (CTM2012-32017) and by the Marine Biogeochemistry and Global Change research group (Generalitat de Catalunya, 2009SGR142). JM was funded by a FPI studentship (BES-2007-16537) and AG by an I3P studentship (I3P-BPD2005) from the Spanish Government ; Peer Reviewed

Background. The Life+ Indemares project (www.indemares.es) aimed to better understand the natural and socioeconomic values of several marine areas along the territorial waters of the Spanish State, leading to an informed decision-making process for the designation of new protected areas for the marine environment. One of the 10 areas selected corresponded to the "South-West Gulf of Lions Canyon System" (https://eunis.eea.europa.eu/sites/ESZZ16001), located in the north-eastern part of the Iberian Peninsula. It includes the submarine canyons of Cap de Creus and Lacaze-Duthiers and their adjacent continental shelf. The Marine Biodiversity, Ecology and Conservation Research Group from the Institute of Marine Sciences of Barcelona (ICM-CSIC) produced a detailed evaluation of the physical and ecological characteristics of the seabed and water column habitats, providing the necessary scientific information for its proposal as a Site of Community Importance to the European Union. Faunistic catalogue. An ecosystem-based approach to the management of Cap de Creus marine area after protection measures are put in place requires a comprehensive knowledge of its benthic ecosystem, which includes the continental shelf and submarine canyon. The methodology employed to identify and characterize its main benthic communities down to 400 m depth was based on images collected through underwater video platforms, such as Remotely Operated Vehicles (ROVs) and manned submersibles. The involvement of taxonomists allowed for the identification of most of the organisms observed in the images down to species or genus level, a task that could only be achieved due to the high-quality footage recorded and the set of biological samples collected. This detailed work led to the development of a photographic catalogue that served as basis for the set of ecological studies developed subsequently. Acknowledging that the identification of benthic species from imagery still has its caveats, we felt that this faunistic inventory should be made ...

ABSTRACT. The deep sea plays a critical role in global climate regulation through uptake and storage of heat and carbon dioxide. However, this regulating service causes warming, acidification and deoxygenation of deep waters, leading to decreased food availability at the seafloor. These changes and their projections are likely to affect productivity, biodiversity and distributions of deep-sea fauna, thereby compromising key ecosystem services. Understanding how climate change can lead to shifts in deep-sea species distributions is critically important in developing management measures. We used environmental niche modelling along with the best available species occurrence data and environmental parameters to model habitat suitability for key cold-water coral and commercially important deep-sea fish species under present-day (1951–2000) environmental conditions and to project changes under severe, high emissions future (2081–2100) climate projections (RCP8.5 scenario) for the North Atlantic Ocean. Our models projected a decrease of 28%–100% in suitable habitat for cold-water corals and a shift in suitable habitat for deep-sea fishes of 2.0°–9.9° towards higher latitudes. The largest reductions in suitable habitat were projected for the scleractinian coral Lophelia pertusa and the octocoral Paragorgia arborea, with declines of at least 79% and 99% respectively. We projected the expansion of suitable habitat by 2100 only for the fishes Helicolenus dactylopterus and Sebastes mentella (20%–30%), mostly through northern latitudinal range expansion. Our results projected limited climate refugia locations in the North Atlantic by 2100 for scleractinian corals (30%–42% of present-day suitable habitat), even smaller refugia locations for the octocorals Acanella arbuscula and Acanthogorgia armata (6%–14%), and almost no refugia for P. arborea. Our results emphasize the need to understand how anticipated climate change will affect the distribution of deep-sea species including commercially important fishes and foundation ...