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The knowledge and control of invasive species are essential in the management of marine ecosystems. The Mediterranean Sea is one of the marine areas with the highest number of invasive species detected, most of them invertebrates. On a smaller scale, colonization by non-native species in coastal lagoons depends directly on their connectivity with the adjacent sea and on the changes in their environmental conditions induced mainly by human interventions. In this study, the cirratulid species Timarete caribous Grube, 1859, native from the Western and Central Atlantic Ocean, was detected for the first time in a Western Mediterranean coastal lagoon, the Mar Menor. It has been found in dense aggregates on both artificial and natural rocky substrates, mainly in the most important communication channel with the Mediterranean Sea. Following the evolution of this NIS will be important for understanding the dynamic and spread of the species and its possible effects on the indigenous biological communities

Publisher: Pensoft Publishers; International audience; Truly sustainable development in a human-altered, fragmented marine environment subject to unprecedented climate change, demands informed planning strategies in order to be successful. Beyond a simple understanding of the distribution of marine species, data describing how variations in spatio-temporal dynamics impact ecosystem functioning and the evolution of species are required. Marine Functional Connectivity (MFC) characterizes the flows of matter, genes and energy produced by organism movements and migrations across the seascape. As such, MFC determines the ecological and evolutionary interdependency of populations, and ultimately the fate of species and ecosystems. Gathering effective MFC knowledge can therefore improve predictions of the impacts of environmental change and help to refine management and conservation strategies for the seas and oceans. Gathering these data are challenging however, as access to, and survey of marine ecosystems still presents significant challenge. Over 50 European institutions currently investigate aspects of MFC using complementary methods across multiple research fields, to understand the ecology and evolution of marine species. The aim of SEA-UNICORN, a COST Action within the European Union Horizon 2020 framework programme, is to bring together this research effort, unite the multiple approaches to MFC, and to integrate these under a common conceptual and analytical framework. The consortium brings together a diverse group of scientists to collate existing MFC data, to identify knowledge gaps, to enhance complementarity among disciplines, and to devise common approaches to MFC. SEA-UNICORN will promote co-working between connectivity practitioners and ecosystem modelers to facilitate the incorporation of MFC data into the predictive models used to identify marine conservation priorities. Ultimately, SEA-UNICORN will forge strong forward-working links between scientists, policy-makers and stakeholders to facilitate the integration of MFC knowledge into decision support tools for marine management and environmental policies.

The excess input of nutrients that triggers eutrophication processes is one of the main destabilizing factors of coastal ecosystems, being coastal lagoons prone to suffer these effects and present dystrophic crises. This process is aggravated by the current trend of rising temperatures and more frequent torrential rains due to climate change. We observed that the Mar Menor lagoon had a great capacity for self-regulation of its trophic web and resistance to the eutrophication process, but after 30 years of nutrient input due to the change in the agricultural regime in its drainage basin in the 1990s, the lagoon ecosystem has suffered several of these events. In this work, we characterize the seasonal dynamic of the pelagic system during the last dystrophic crises. Phosphorus and nitrogen alternate as the limiting nutrient for phytoplankton proliferation. The entrance of phosphorus is mainly related to vacation periods, while nitrogen inputs, both superficial and sub-superficial, are more related to chronic high nitrates concentration in the water table after the agricultural activities carried out in the area changed. Our analysis reveals that the summer season is prone to suffer periodical hypoxia events when the N/P ratio decreases, and the temperature rises. In the Mar Menor, the ecological balance has been maintained in recent decades thanks to, among other mechanisms, the spatial and temporal segregation of top-down control over phytoplankton exerted by three species of jellyfish. However, the deep reduction in the abundance of the summer jellyfish species and the excessive proliferation of phytoplankton has meant the loss of this control. Moreover, we have registered a decline in the abundance of all the other zooplanktonic groups during the dystrophic crises. We suggest that management actions should address the input sources of water and nutrients, and an integrated management of the activities carried out throughout the watershed.

142 scientific publications have been reviewed on the characteristics of the scyphozoans with respect to their ability to develop blooms and the most significant environmental characteristics that determine them. Special attention was paid to depth, temperature, salinity, chlorophyll concentration, and the habitat of the 39 registered blooming genera. After the review, we find that over the past decades, the number of scyphozoan blooming-species is higher than previously recorded, increasing from circa 14% to 25% of the class. Species that inhabit depths less than 27.1 m are prone to produce blooms, particularly in semienclosed areas with low rates of water renewal and high thermal amplitudes. Temperature appears as the main environmental factor controlling blooms, but food availability is essential to sustain the proliferations. Interspecies variability in the response to environmental factors observed in this work suggest that bloom predictive models should be constructed species-habitat-specific.

How far do marine larvae disperse in the ocean? Decades of population genetic studies have revealed generally low levels of genetic structure at large spatial scales (hundreds of kilometre). Yet this result, typically based on discrete sampling designs, does not necessarily imply extensive dispersal. Here, we adopt a continuous sampling strategy along 950 km of coast in the Northwestern Mediterranean Sea to address this question in four species. In line with expectations, we observe weak genetic structure at a large spatial scale. Nevertheless, our continuous sampling strategy uncovers a pattern of isolation by distance at small spatial scales (few tens of kilometre) in two species. Individual-based simulations indicate that this signal is an expected signature of restricted dispersal. At the other extreme of the connectivity spectrum, two pairs of individuals that are closely related genetically were found more than 290 km apart, indicating long-distance dispersal. Such a combination of restricted dispersal with rare long-distance dispersal events is supported by a high-resolution biophysical model of larval dispersal in the study area, and we posit that it may be common in marine species. Our results bridge population genetic studies with direct dispersal studies and have implications for the design of marine reserve networks.

Usually, suspension feeding holothurians are considered as passive suspension feeders because they depend exclusively on ambient water movements. In general, suspension feeders, and in particular passive suspension feeders, have structures (tentacles, tube beet, arms, etc.) that enhance the rate of particle capture by changing the scale of turbulence in the water, in terms of the number of Reynolds. As more long are the filtration structures, more turbulent became the flux.

Tackling environmental problems not only requires the detection of harmful agents or the drivers that induce changes in ecosystems and their effects, but also knowledge of their action mechanisms and the processes involved in order to design solutions, recover the damaged systems and, above all, prevent any deterioration before it occurs. In recent years conservation physiology has been proposed as a discipline that could play an important role in this context. However, the main problem in generalizing physiological indicators in order to assess ecological status is the leap in scale from the internal physiology of an individual to its relevance for ecosystem functioning. In this paper, we propose that the study of the physiological bases and epigenetic mechanisms that determine the allocation of energy resources, in the context of Dynamic Energy Budget theory, can be the hinge that allows us to pass from the physiology of the individual to the scale of population dynamics, the structure of populations and ecosystems. This proposal is based on the strong relationship shown by the parameters of the life story of individuals, such as body growth rate, maximum size, life expectancy or generation time, with the parameters that determine population growth and the ecological strategies of the species. There is growing evidence that the relationship between these parameters is not completely fixed and does not only respond to evolutionary scales, but may be flexible within certain limits throughout ontogeny and the life of individuals, producing consequences in populations in response to environmental conditions, environmental stress and, in the case of fish, the effects of fishing. Lay summary Biological index to detect environmental impacts can be applied from cell to ecosystem scale. However, at lower levels, although they give important information on the mechanisms involved it is difficult to infer the real consequences of the detected changes on the ecosystems. The review of the regularities existing in ecological guilds relationships of fishes suggests that the study of the physiological and epigenetic bases that determine the allocation of energy resources in the context of Dynamic Energy Budget theory can be the hinge that allows us to pass from the effects on the physiology of the individual to the scale of population dynamics and ecosystems when modelling the consequences of changes in environmental stress.

Coastal lagoons count among the marine habitats with the highest biological productivity, playing an important ecological role. Together with wetlands in general and coral reefs, they are also amongst the habitats with the highest value derived from the services they provide. This work aims to assess the natural goods and services provided by the Mar Menor coastal lagoon in Murcia (Spain), as well as the environmental risks it is exposed to. This ecosystem, as many coastal lagoons throughout the world, supports a great variety of important services but the resulting pressures are also the reasons that have led to its deterioration, showing signs of impact, whether environmental, social and even economic. In 2011 the European Commission proposed a common strategy on biodiversity, in an attempt to avoid its decline, and claim it as one of the main bases for sustainable economic development. In this context, this work also looks at the socioeconomic value of this emblematic environment using the contingent valuation method (CVM). A questionnaire was developed and presented to inhabitants and visitors of the Mar Menor area, including a broad representation of professions and activities, to identify stakeholder perception of the environment and how they evaluate the importance of ecological processes for maintaining ecosystem functioning and the goods and services provided. The perception and valuation of goods and services provided by ecosystem functioning and biodiversity in the Mar Menor lagoon depended on the different groups considered (by age, professional activity, residence, educational background or sex), although in general, stakeholders, including fishermen, perceived that tourism services are the most important. Interestingly, the sectors related to construction and fishing were well aware of the risks derived from their own activities. The evaluation of services and the perception of the principal environmental risks and impacts were high for all the groups of users considered, and the indirect use and non-use value of the lagoon ecosystem conservation was established in 43,326,181 Euros/year.

International audience; The study of organism dispersal is fundamental for elucidating patterns of connectivity between populations, thus crucial for the design of effective protection and management strategies. This is especially challenging in the case of coastal fish, for which information on egg release zones (i.e. spawning grounds) is often lacking. Here we assessed the putative location of egg release zones of the saddled sea bream (Oblada melanura) along the southeastern coast of Spain in 2013. To this aim, we hindcasted propagule (egg and larva) dispersal using Lagrangian simulations, fed with species-specific information on early life history traits (ELTs), with two approaches: 1) back-tracking and 2) comparing settler distribution obtained from simulations to the analogous distribution resulting from otolith chemical analysis. Simulations were also used to assess which factors contributed the most to dispersal distances. Back-tracking simulations indicated that both the northern sector of the Murcia region and some traits of the North-African coast were hydrodynamically suitable to generate and drive the supply of larvae recorded along the coast of Murcia in 2013. With the second approach, based on the correlation between simulation outputs and field results (otolith chemical analysis), we found that the oceanographic characteristics of the study area could have determined the pattern of settler distribution recorded with otolith analysis in 2013 and inferred the geographical position of main O. melanura spawning grounds along the coast. Dispersal distance was found to be significantly affected by the geographical position of propagule release zones. The combination of methods used was the first attempt to assess the geographical position of propagule release zones in the Mediterranean Sea for O. melanura, and can represent a valuable approach for elucidating dispersal and connectivity patterns in other coastal species.

Coastal lagoons are transitional ecosystems between epicontinental aquatic systems, transitional waters, and coastal marine ecosystems. This border situation determines the existence of intense gradients that make them globally one of the most productive ecosystems, but at the same time they can develop communities with an important diversity and complex mechanisms of self-regulation. In addition, despite their small size compared to the ocean, the lagoonal influence on the genetic diversity of marine populations, adaptations to climate change of marine species and even in the oceanographic conditions of the adjacent sea is much greater than expected. All of this makes them very unique ecosystems that provide an important number of ecosystem services and societal goods and benefits. This translates into increasing anthropogenic pressures in which a deep knowledge of lagoonal functioning and organization is needed in order to manage them efficiently; this becomes more important in a future scenario that tends to increase pressures in a framework of climate change. However, this knowledge is still limited and has been conditioned by previous assumptions that are gradually being reconsidered. This highlights the importance of international collaboration in research networks for the comparison of the great variety of coastal lagoons environments in order to extract their singularities and regularities in order to deepen our knowledge of these important ecosystems.

Achieving sustainable use of kelps is key for small-scale fishers’ livelihoods and biodiversity. During the last three decades, Chile has implemented different policy approaches to manage kelps. Unfortunately, assessments of the biological impacts of these management regimes have not received the attention they deserve. In this study, we explore biomass, density, size structure and holdfast diameter/stipe length relation of the kelp Lessonia spp., associated to a territorial user rights policy, which grant exclusive access to fishers, and a regional management plan policy which defines control rules in what were historically de facto open access areas. We compare these with marine protected areas where harvesting is banned, thus serving as a benchmark. The study was performed along the coast of two of the main kelp harvesting regions of Chile. The analyses, performed in two time periods, shows that biomass is greater inside areas managed through territorial user rights and in marine protected areas compared to areas where regional management plans have been implemented, which perform in a similar way to open access sites. Enforcement is a key driver of kelp response. Densities of recruits and juveniles are higher in areas where harvesting and gathering are allowed, whilst adult plants have higher density in marine protected areas. In all cases, kelps have become denser after eleven years. The holdfast diameter/stipe length relation provides an indicator of protection efficiency: stricter regulatory measures are related to larger holdfast diameters and shorter stipes. We conclude that, in general, territorial user rights policies and marine protected areas have contributed to the conservation of wild intertidal Lessonia populations. Results highlight the potential of the regional management plans policy to improve kelp management, but it will probably need important adjustments to enhance enforcement and compliance. In addition management innovations such as rotational harvest strategies could provide an important complement which should be further assessed.

Connectivity among marine populations plays a fundamental role in the dynamic of metapopulations and communities. Moreover, genetic connectivity is important for the evolutionary history and adaptive capability of species while demographic connectivity is essential to maintain ecological processes. In coastal lagoons, isolation degree or confinement is considered the main factor structuring biological assemblages. These environments also function as nursery areas for many marine species that colonize the lagoons as larvae or juveniles, returning to the sea for reproduction. It is therefore essential to know the connectivity between lagoons and sea for the management of biodiversity and the exploitation of coastal living resources. This work anases the role that connectivity between coastal lagoons and sea plays in the assemblages and subpopulations structure of the first. To this purpose, a finite element hydrodynamic model was used coupled with a lagrangian module to simulate the potential exchange of organisms between Mar Menor lagoon (Western Mediterranean) and the adjacent sea. Connectivity parameters from 40 stations, located inside and outside the Mar Menor, have been estimated. The outcomes of the eight simulations carried out were compared with field data, including ichthyoplankton species composition and genetic fluxes in 6 species with different life stories. The results suggest that pelagic larval phases are longer than expected or the species can extend PLD within certain limits if the conditions for the settlement are not adequate. Repetition can improve the chance of self-recruitment, coupling larval duration, competency period and finding the adequate location for settlement. The results also show that connectivity between all lagoon and Mediterranean stations is very low and is independent of geographical distance. There is a strong asymmetry in the probability of receiving particles, being lower the probability of colonization of the lagoon stations from the sea than vice versa. Despite its low values, connectivity can explain up to 65% of the similarities in species composition of the ichthyoplankton and between 30 and 96% of the variance in genetic differentiation of the studied species. The low value of connectivity and colonization rates is enough, however, to maintain the genetic fluxes between populations and, at the same time, restricted connectivity can play an important role in maintaining high diversity and heterogeneous assemblage structure. Connectivity among marine populations plays a fundamental role in the dynamic of metapopulations and communities. Moreover, genetic connectivity is important for the evolutionary history and adaptive capability of species while demographic connectivity is essential to maintain ecological processes. In coastal lagoons, isolation degree or confinement is considered the main factor structuring biological assemblages. These environments also function as nursery areas for many marine species that colonize the lagoons as larvae or juveniles, returning to the sea for reproduction. It is therefore essential to know the connectivity between lagoons and sea for the management of biodiversity and the exploitation of coastal living resources. This work anases the role that connectivity between coastal lagoons and sea plays in the assemblages and subpopulations structure of the first. To this purpose, a finite element hydrodynamic model was used coupled with a lagrangian module to simulate the potential exchange of organisms between Mar Menor lagoon (Western Mediterranean) and the adjacent sea. Connectivity parameters from 40 stations, located inside and outside the Mar Menor, have been estimated. The outcomes of the eight simulations carried out were compared with field data, including ichthyoplankton species composition and genetic fluxes in 6 species with different life stories. The results suggest that pelagic larval phases are longer than expected or the species can extend PLD within certain limits if the conditions for the settlement are not adequate. Repetition can improve the chance of self-recruitment, coupling larval duration, competency period and finding the adequate location for settlement. The results also show that connectivity between all lagoon and Mediterranean stations is very low and is independent of geographical distance. There is a strong asymmetry in the probability of receiving particles, being lower the probability of colonization of the lagoon stations from the sea than vice versa. Despite its low values, connectivity can explain up to 65% of the similarities in species composition of the ichthyoplankton and between 30 and 96% of the variance in genetic differentiation of the studied species. The low value of connectivity and colonization rates is enough, however, to maintain the genetic fluxes between populations and, at the same time, restricted connectivity can play an important role in maintaining high diversity and heterogeneous assemblage structure.

Coastal lagoons are among the most productive systems in the world. Many marine species make use of this by entering the lagoons as juveniles for nursery and growth before returning to the sea for reproduction. Humans take advantage of such fish migration processes by fishing, and exploit the high productivity for aquaculture activities. The Mar Menor is one of the largest coastal lagoons in the Mediterranean, sustaining relatively high fishing intensity despite the fact that it has traditionally been characterized as highly oligotrophic. However, in the last decades, this lagoon has suffered drastic changes induced by human activities. This has led to eutrophication, which started mainly as a consequence of changes in agricultural practices in the lagoon watershed, and triggered such fundamental changes in the system, as the mass development of jellyfish. The aim of this work is to capture and analyse the structure and functioning of the trophic web of the Mar Menor when it was still, in contrast to other coastal lagoons, oligotrophic, to provide a start point for analysing the consequences of changes in the distribution of macrophyte meadows and of eutrophication. We have compiled a detailed trophic model of this lagoon, comprising 94 compartments, using an ECOPATH model to capture the period 1980–1995. At this time the lagoon was an autotrophic system with a high net surplus of production that reached 9124.31gC/m2/year, while the production/biomass (P/B) ratio reached 34.56 and the total primary production/total respiration ratio was 7.01. The lagoon exported a 38.46% of total flows, including the catch by fishing, and 44.40% went to detritus. The primary production was mainly benthic (99.4%) due to the microphytobenthos and macrophytes. However, despite the fact that total fishery landings in the study period ranged between 144,835.5 and 346,708.5 kg, the gross efficiency was low, making up only 0.005% of the net primary production. This could partly be explained by the high trophic level of the fish catch (2.9), but mainly because most of the primary production (10,532.06 gC/m2/year) went directly to the detritus pool and was accumulated in the sediment in the Caulerpa prolifera meadows. We suggest several reasons why such high productivity coincided with low chlorophyll concentrations and good overall water quality: 1) the domination of both benthic biomass and primary production over pelagic ones with a high biomass of filter feeders, detritus feeders and scavengers, 2) high species diversity, complex and long food webs characterized by low connectance,3) the export of a significant part of the production from the system, and 4) the accumulation of surplus organic matter (as detritus) in sediments. We compare the food web of the Mar Menor in this mentioned oligotrophic stage to those of ten other lagoons in pursuit of more general implications regarding lagoon ecosystem functioning.

Blooms of jellyfishes are perceived to have increased during the last decades causing interference with human activities of both recreational and professional type. Those blooms seem to hold correlation with human impacts and environmental changes such as overfishing, the increase of temperature, eutrophication or habitat modification. In this study we perform the first simultaneous analysis of population dynamics from three scyphozoan jellyfishes, Aurelia sp. (Linnaeus, 1758), Cotylorhiza tuberculata (Macri, 1778) and Rhizostoma pulmo (Macri, 1778). The effect of temperature, salinity, ichthyoplankton, nutrients and chlorophyll a concentration have been studied. These three species are present in the Mar Menor coastal lagoon where they show a spatial and temporal segregation of their populations and life cycles that allows them to reduce interspecific competition. Temperature and its seasonal cycle have been determined to be a key factor regulating the populations, triggering the strobilation process either by an increase in temperature (C. tuberculata) or by a decrease in it (Aurelia sp.). Such segregation has a decisive effect on the ecosystem, since it allows a continuous temporal succession of top-down control on the lagoon trophic network.

Tunisia occupies a strategic biogeographic position in the Mediterranean Sea and the Strait of Sicily is considered a biogeographical boundary that separates the eastern and western basins. Despite the importance of marine biodiversity in Tunisia, the few studies of Echinodermata fauna in this region data from long ago. In order to update and produce a validated checklist of the echinoderms that occur in northern Tunisia, a study of this phylum was carried out between 2012 and 2016. Forty-five species were inventoried and distributed into the five living Echinodermata classes (Crinoidea, Asteroidea, Ophiuroidea, Echinoidea and Holothuroidea). New occurrences of four species from Tunisian marine waters [Asterina pancerii (Gasco, 1876), Luidia atlantidea (Madsen, 1950), Ophiactis virens (Sars, 1859) and Leptopentacta tergestina (Sars, 1857)], are cited and discussed here for the first time. Túnez ocupa un área biogeográfica estratégica en el Mediterráneo. El estrecho tunecino-siciliano es considerado una frontera biogeográfica que separa las cubetas oriental y occidental. Sin embargo, a pesar de su interés, los estudios sobre la fauna de equinodermos de Túnez son antiguos y escasos. Con el fin de elaborar el inventario de los equinodermos de la región septentrional del mar de Túnez, se realizó un estudio de este filum entre los años 2012 y 2016. Se han inventariado cuarenta y cinco especies pertenecientes a las cinco clases actuales de Echinodermata (Crinoidea, Asteroidea, Ophiuroidea, Echinoidea y Holothuroidea). Cuatro especies [Asterina pancerii (Gasco, 1876), Luidia atlantidea (Madsen, 1950), Ophiactis virens (Sars, 1859) y Leptopentacta tergestina (Sars, 1857)] se han recolectado por primera vez en estas aguas.

Environmental stress influences biological assemblages, with species responding to stress by adopting particular life-history strategies (e.g., r vs. K ). Coastal lagoons and estuaries are considered naturally stressed and physically controlled systems with frequent environmental disturbances and fluctuations. At the same time, their transitional nature (between terrestrial, freshwater and marine) makes them especially vulnerable to human impacts and land and freshwater inputs. As a result, it is hypothesised that residents of coastal lagoons would display characteristics of r -selected species. The r -strategy involves increased reproductive effort through early reproduction, small and numerous offspring with a large dispersive capability, short lifespan and small adult body size. Together, these traits provide a selective advantage in such unpredictable or short-lived environments. Alternatively, immigrants to coastal lagoons should mostly be K -strategists, with a competitive advantage over the r -strategists, at least on a temporary time scale. These hypotheses were explored using a dataset from 73 Atlanto-Mediterranean sites: 27 estuaries, 42 coastal lagoons and 4 from the sea, obtained from published sources. A detailed analysis of the distributions of the different resident fish species according to lagoon characteristics indicated that in lagoons with a higher marine influence the families Gobiidae, Blenniidae and Syngnathidae were common, while lagoons with freshwater influence are characterized by Cyprinidae and other freshwater species. In analyzing the biological strategies of lagoon species we found that fish assemblages inhabiting marine influenced lagoons were characterized by solitary, necto-benthonic sedentary species. These species are often hermaphroditic, with benthic broods and many exhibit brooding behaviour. This suggests that marine influenced lagoons are dominated by K -strategist species, while r -strategy species will be more common in freshwater lagoons and among marine migrant species.

Phytoplankton community' dynamics were studied in Salgados coastal lagoon in order to evaluate the effects of excessive organic loads and also physical stress caused by the irregular opening of the lagoon. Salgados is a hypereutrophic intermittently open coastal lagoon, which received freshwater inputs from small rivers and from a wastewater treatment plant. Cyanophyceae dominated the phytoplankton communities most of the time; Bacillariophyceae became the main taxonomic group in winter when the lagoon was closed; Chlorophyceae was the major class in early summer; pico-nano flagellate algae accounted for a high percentage of total phytoplankton during spring. Potentially harmful taxa were observed during most of the sampling periods, forming blooms and accounting for a considerable percentage of total phytoplankton abundance. A strong differentiation among dry and wet seasons could be noticed. The dry season was dominated by Microsystis aeruginosa , Rhodomonas sp., pico-nano flagellate algae, Cyclotella spp. and Planktothrix sp., while the wet season, although still with the presence of Microsystis aeruginosa , was dominated by Dolichospermum spiroides . The best environmental variables explaining stations patterns and based on phytoplankton taxa were days of isolation, pH, and salinity. Temperature, cumulative rain and total phosphorus were also related with species and stations patterns. The high nutrient load in Salgados lagoon promoted the development and persistence of harmful algae blooms. Proper management of coastal lagoons involves not only the control of direct discharges of nutrients, but also of other factors, including water level and communication with the sea.

Benthic macroinvertebrate communities and environmental conditions were studied in two intermittently closed and open coastal lakes and lagoons (ICOLLs), located in southern Algarve (Foz do Almargem e Salgados), with the purpose of evaluating the effects of organic pollution, originated mainly from wastewater discharges, and the physical stress caused by the irregular opening of the lagoons. Most of the year, lagoons were isolated from the sea, receiving the freshwater inputs from small rivers and in Salgados, also from the effluents of a wastewater plant. According to environmental and biotic conditions, Foz do Almargem presented a greater marine influence and a lower trophic state (mesotrophic) than Salgados (hypereutrophic). Benthic macroinvertebrate communities in the lagoons were distinct, just as their relations with environmental parameters. Mollusca were the most abundant macroinvertebrates in Foz do Almargem, while Insecta, Oligochaeta and Crustacea were more relevant in Salgados. Corophium multisetosum occurred exclusively in Salgados stations and, just as Chironomus sp., other Insecta and Oligochaeta, densities were positively related to total phosphorus, clay content and chlorophyll a concentration in the sediment, chlorophyll a concentration in water and with total dissolved inorganic nitrogen. Abra segmentum, Cerastoderma glaucum, Peringia ulvae and Ecrobia ventrosa occurred only in Foz do Almargem, with lower values of the above mentioned parameters. Both lagoons were dominated by deposit feeders and taxa tolerant to environmental stress, although in Salgados there was a greater occurrence of opportunistic taxa associated to pronounced unbalanced situations, due to excess organic matter enrichment.

Mediterranean coastal lagoons are among the most productive of marine ecosystems but, at the same time, they are strongly affected by anthropogenic pressures that could alter their fisheries. This work looks at how the Mar Menor coastal lagoon fishery evolved from the eighteenth century to 2012, and provides data about landings, effort and gears. The relationships between fishing yields and the environmental consequences of the most important human activities in the lagoon (including the dredging and widening of inlets in the last two centuries and eutrophication episodes in the 1990s) are examined using uni- and multi-variate analysis. While mean total yield tended to remain constant, significant changes in the specific composition of the catch and in the dominance of the main target species have occurred. The lagoon seems to have the ability to support a wide range of pressures and environmental changes, since it has been seen to recover each time from specific human impacts, maintaining the fishery yields close to the total maximum sustainable yield. However, other factors, like climate change or the spread of aquaculture exploitations, may have overlapping effects, introducing long term trends in the fisheries concerned.

Seagrass communities are under direct threat as a result of anthropogenic impact and competition with macroalgae. Present day macrophyte meadows in the Mar Menor are the result of successive colonization events, associated with changes in the hydrographical conditions. In the last of these events, Caulerpa prolifera (Forsskal) J.V. Lamouroux colonized the lagoon in the early 1970's following the widening and deepening of the El Estacio inlet into a navigation channel, which caused a substantial decrease in the salinity level and a lower annual water temperature range. The seaweed C. prolifera expanded rapidly and replaced the previous seagrass meadows with monospecific algae meadows or with meadows mixed with the seagrass Cymodocea nodosa (Ucria) Ascherson. This work analyzes the factors that explain the distribution of macrophyte meadows and their evolution, as well as subsequent sediment alterations. The mean biomass of C. prolifera ( Ca ) in the deeper areas of the Mar Menor increased from 1982 to 1987 and remained constant thereafter until 2008, while the mean biomass of C. nodosa ( Cy ) showed a continuous decrease during the same period. The evolution of the Ca / Cy ratio showed a progressive expansion of C. prolifera monospecific meadows from north to south. The decline in the C. nodosa meadows was more pronounced in the deeper areas and was especially verified in the inner or more confined areas. At present, monospecific C. nodosa meadows are restricted to the southern and western, shallowest areas of the lagoon. The negative relationship between Caulerpa prolifera and Cymodocea nodosa shown by multiple regressions suggests that there is a competition between the two species. A complex interaction of factors could be responsible for the equilibrium and evolution of the relationships between both species in the Mar Menor. In shallow waters, coarse sediments, high light levels and physiological adaptations could favour C. nodosa . In deeper areas, light scarcity might limit C. nodosa biomass, but a negative effect of C. prolifera through increasing the sediment silt content, sulphide production, organic matter and anoxia, cannot be ruled out.

Different approaches based on macrophytes have been proposed in recent years to implement the European Water Framework Directive. However, their application to transitional environments presents difficulties as a consequence of the natural gradients of environmental conditions in these ecosystems. Three of the most widely used methodological approaches, the EEI, E-MaQI and BENTHOS index were applied under different stress conditions in order to evaluate their suitability for detecting anthropogenic pressures in coastal lagoons. For this purpose, 12 representative sampling stations were selected, including sites that suffer the greatest pressures in the Mar Menor (agricultural and urban wastes that reach the lagoon through the principal watercourses, and pleasure harbours) as well as sites considered to be in good ecological condition. Species respond not only to eutrophication and nutrient concentration gradients, but also to natural environmental stress and confinement. The assessment of stations according to substrate type differed between EEI and E-MaQI, the correlation between the scores assigned by each index being very low. Moreover, the explanatory variables selected by the regression models (GLM) show that the tested indices mainly respond to natural environmental stress and, only after excluding these variables from the analyses, did the relationship of the indices with eutrophic parameters, such as chlorophyll a or ammonium concentration, become evident.

Aquatic ecosystems, water resources and their management are some of the main problems facing humanity. These problems vary from water scarcity and deteriorating quality for human consumption and use, to floods in areas with torrential rainfall, rising sea levels in coastal zones, the overexploitation of living resources and the loss of ecological quality and biodiversity. Proper water management needs to follow a hierarchical perspective, ranging from the whole planet to individual water bodies. Spatio-temporal scales change at each level, as do driving forces, impacts, and the processes and responses involved. Recently, the European Union adopted the Water Framework Directive (WFD) to establish the basic principles of sustainable water policy in member states, one of the main concerns being the need to consider the vulnerability of coastal aquatic ecosystems and to establish their ecological status. However, from a Mediterranean point of view, the actions of European countries (under the WFD regulations) and non-EU countries need to be coordinated. There are more than 100 coastal lagoons in the Mediterranean. They are habitats with an important ecological role, but also provide essentials goods and services for humans. In the present work, we look at the problems involved in understanding their definition and management. At water body management level, we emphasise that scientific cooperation is necessary to deal with the conceptual and ecological difficulties derived from inter and intra-lagoon variability in hydrology and biological assemblages, inherent factors in the functioning of these complex ecosystems.

The European Water Framework Directive (WFD) establishes a well differentiated typology of water bodies on the basis of scientific and biological criteria. For coastal waters, such criteria have long been established, while for transitional waters they are still under discussion. One of the difficulties when applying the WFD to coastal lagoons is to include them in only one of these categories, and while there is no doubt about the nature of estuaries as transitional waters, there is some controversy concerning lagoons. To what extent, reference conditions may be similar for estuaries and lagoons, or whether features common to all coastal lagoons are more important for differentiating them from other water bodies than the fact that there is (or is not) any fresh water influence, is something that remains unclear and is discussed in this work. Coastal lagoons and estuaries form part of a continuum between continental and marine aquatic ecosystems. Shelter, strong boundaries or gradients with adjacent ecosystems, anomalies in salinity regarding freshwater or marine ecosystems, shallowness, etc. all contribute to the high biological productivity of estuaries and lagoons and determine common ecological guilds in the species inhabiting them. On the other hand, fresh water influence, the spatial organization of gradients and environmental variability (longitudinal one-dimensional gradients in estuaries versus complex patterns and three-dimensional heterogeneity in lagoons) constitute the main differences, since these factors affect both the species composition and the dominance of certain ecological guilds and, probably, the system’s complexity and homeostatic capability. In the context of the WFD, coastal lagoons and estuaries are closer to each other than they are to continental or marine waters, and, on the basis of the shared features, they could be intercalibrated and managed together. However, coastal lagoons cannot be considered transitional waters according to the present definition. To assume that fresh water influence is an inherent characteristic to these ecosystems could lead to important changes in the ecological organization and functioning of coastal lagoons where natural fresh water input is low or null. In our opinion, the present day definition of transitional waters should be changed substituting the criterion of fresh water influence by another based on common features, such as relative isolation and anomalies in salinity in water bodies with marine influence. Otherwise, coastal lagoons should be considered a particularly characteristic type of water mass for establishing reference conditions of ecological status.

The role of Marine Protected Areas on distinct life stages of Mediterranean reef fish species (classified on the basis of their economic value and mobility categories) was assessed in a network of marine reserves in SE Spain. Only abundance and biomass of adult of both commercial and demersal species were positively affected by protection. Gradients across reserve boundaries (as a clue to the occurrence of spillover) were observed for fish abundance but not for biomass, indicating a protected fish assemblage with a predominance of small-sized individuals. Also, post-larvae of commercial species were negatively related to protected zones. Active selection of settlement preferred habitats, larval accumulation favoured by the geomorphological configuration of the coast or mixed effects has been proposed as possible explanations. Juveniles showed high spatial variability resulting in a lack of response to fishing protection measures. We highlight the need of including early life stages and overall suitable habitats for them when designing MPA networks due to the crucial importance of these stages to successful fulfillment of MPA objectives.

As coastal lagoons serve as nursery areas for some marine and estuarine fish, selective pressures of these brackish or hypersaline lagoons may influence the genetic structure of species and populations. We examined spatial and temporal genetic patterns at eight microsatellite loci in white seabream [Diplodus sargus (Linnaeus 1758)] recruits from the Mar Menor (Southeast Spain) and compared these loci with those in coastal populations from the open sea, observing a high degree of genetic diversity and spatio-temporal genetic stability. However, the results suggest the presence of subpopulations or genetic substructures in the Mar Menor D. sargus population that could be interpreted as a homogeneous mixture of individuals from three differentiated subpopulations in the Mediterranean and evidence of the Wahlund effect. It also suggests that D. sargus adults return to their original spawning habitat, thus conserving the genetic differences among the respective populations over time. Overall, this study demonstrates the importance of the Mar Menor coastal lagoon as a nursery area for the conservation of genetic diversity of D. sargus populations.

The present study aimed at exploring the habitat use by fish life stages and ontogenetic shifts in a South-western Mediterranean rocky reef. The relation with rocky reef habitat structure (complexity, heterogeneity, total cover and depth) was visually surveyed on a monthly basis, in four locations and during one year, for the abundance of young-of-the-year (YOY) and juvenile reef fish. Fish assemblage responded significantly to spatial and temporal variations of structural microhabitat, this response being species-specific. Abundance of fish life stages was directly related to temperature variation, with higher abundances occurring on warmer months. Also, habitat differences occurred between YOY and juveniles of a series of species from shallow steeper rocky habitats to deeper complex rocky bottoms with high total cover. Spatial differences in YOY and juvenile abundance across locations could be attributed to fine-scale habitat preference, from purely rocky, more complex sites, with greater slopes and depths, to sites harbouring more heterogeneous habitats. By characterising the microhabitat association of fish life stages (both YOY and juveniles), and identifying for what species this influence may interfere with spatial and temporal patterns, the present study can be used as a basis for pluriannual monitoring of fish recruitment success in the area in order to better understand their population dynamics.

To detect changes in ecosystems due to human impact, experimental designs must include replicates at the appropriate scale to avoid pseudoreplication. Although coastal lagoons, with their highly variable environmental factors and biological assemblages, are relatively well-studied systems, very little is known about their natural scales of variation. In this study, we investigate the spatio-temporal scales of variability in the Mar Menor coastal lagoon (SE Spain) using structured hierarchical sampling designs, mixed and permutational multi-variate analyses of variance, and ordination multi-variate analyses applied to hydrographical parameters, nutrients, chlorophyll a and ichthyoplankton in the water column, and to macrophyte and fish benthic assemblages. Lagoon processes in the Mar Menor show heterogeneous patterns at different temporal and spatial scales. The water column characteristics (including nutrient concentration) showed small-scale spatio-temporal variability, from 10 0 to 10 1 km and from fortnightly to seasonally. Biological features (chlorophyll a concentration and ichthyoplankton assemblage descriptors) showed monthly changes and spatial patterns at the scale of 10 0 (chlorophyll a) e 10 1 km (ichthyoplankton). Benthic assemblages (macrophytes and fishes) showed significant differences between types of substrates in the same locality and between localities, according to horizontal gradients related with confinement in the lagoon, at the scale of 10 0 e10 1 km. The vertical zonation of macrophyte assemblages (at scales of 10 1 e10 2 cm) overlaps changes in substrata and horizontal gradients. Seasonal patterns in vegetation biomass were not significant, but the significant interaction between Locality and Season indicated that the seasons of maximum and minimum biomass depend on local environmental conditions. Benthic fish assemblages showed no significant patterns at the monthly scale but did show seasonal patterns. 2007 Elsevier Ltd. All rights reserved.

Population connectivity scales are important tools to achieve a mechanistic understanding of the factors regulating the abundance and distribution of marine populations and therefore support conservation actions to manage fisheries and stocks. We used 10 microsatellites markers on mullets' samples across the Spanish coast to determine the spatial scale of gene flow as well as the origin of post-larvae caught inside two MPAs. Population structure varied from complete homogeneity for Mullus barbatus, to high spatial variability in Mullus surmuletus samples. Differential habitat utilization by species, geomorphological features and oceanographic patterns are discussed as potential causes of patterns observed. Although we were unable to verify the origin of most post-larvae caught inside MPAs we suggest that they may act as genetic reservoirs due to high heterozigosity levels found in adult specimens inside (M. surmuletus) and nearby (both) them. Our results indicate that early life history traits (i.e. larvae) may not be the only determinant on species dispersal capability, suggesting that other mechanisms such as fine scale adult or juvenile movement may have been underestimated as promoting population connectivity.

Light traps have been used worldwide to sample pre-settlement stages as a good estimator of larval availability and distribution to nearshore habitats; however few studies have been performed to date in temperate environment, such as Mediterranean rocky reefs. Here we describe the spatial and temporal variability of post-larval assemblage in the south-western Mediterranean Sea using light traps, and the effects of environmental variables on their abundances. We sampled 2 coastal localities with 9 light-traps for 2 consecutive nights during 13 months. Post-larval occurrence presented a seasonal pattern in which greater abundances and richness occurred during summer and autumn months. Sea surface temperature, currents and winds were the most important variables related to larval abundance. Important spatial differences in terms of diversity and post-larval abundances were found in an area protected from fishing. Although not tested, we suggest that 1) bottom morphology, 2) presence and distribution of habitat types in coastal areas, including those of adults, 3) local oceanographic conditions, and 4) direct and indirect MPA effects, may influence post-larval distribution, resulting in fine-scale spatial differences. These results reinforce the need to undertake further studies on early life stages of fishes to better understand the dynamic of coastal fish populations.

Post-settlement events can significantly alter the density distribution of settlers and subsequently the adult population structure. The temporal and inter-annual variability of settlement and the effects of mortality on recruitment were investigated across 2 years in the vicinities of Cabo de Palos–Islas Hormigas Marine Reserve by visual census and light trap sampling. Settlement was seasonal with greater species richness and abundance in summer. Although temporal synchronization was observed between larval supply and settlement, densities of settlers could not be predicted from post-larval abundances. Timing of settlement was consistent between years but with high inter-annual variation in abundance. High mortality (~80 %) and general decoupling between post-larval and settlement stages suggest that early mortality is driving such patterns. Nevertheless, indications of habitat-mediated mortality were found for benthic species such as Symphodus and Diplodus, highlighting the importance of habitat in shaping population demography.

Servicio de Pesca y Acuicultura (D.G. Producción Agrícola, Ganadera y del Medio Marino, Consejería de Agua, Agricultura, Ganadería, Pesca y Medio Ambiente, Comunidad Autónoma de la Región de Murcia), y Fondo Europeo Marítimo y de la Pesca (FEMP)

The physiological status of Cystoseira compressa, Padina pavonica and Palisada tenerrima was studied by in vivo chlorophyll fluorescence, pigment content, stoichiometry (C:N), accumulation of UV photoprotectors and antioxidant activity; comparing their photosynthetic response in a coastal lagoon (Mar Menor) and in Mediterranean coastal waters. In general, the specimens reached their highest ETRmax in spring in the Lagoon, but in summer in the Mediterranean, coinciding with their maximum biomass peak. The species exhibited a dynamic photoinhibition. Except C. compressa, they showed a lower decrease in Fv/Fm and higher recovery rates in the Mediterranean populations when exposed to high irradiance. The higher salinity and temperature of the lagoon could impair the photoprotection mechanisms. The acclimation to lagoon environments is species-specific and involves complex regulatory mechanisms. The results underline the importance of N in repair, avoidance, quenching and scavenging mechanisms. In general, Lagoon specimens showed higher pigment concentration. Although xanthophylls play important photo-protective and antioxidant roles, the observed trend is more likely to be explained by the higher temperatures reached in the lagoon compared to Mediterranean. Therefore the studied photosynthetic and biochemical mechanisms can be effective not only for high irradiance, but also for higher temperatures in a climate change scenario, but are highly dependent on nutrient availability.

Coastal lagoons are considered to be among the most productive ecosystems in the world. Many of them support important fisheries, and some of them maintain intensive and extensive aquacultural exploitations. Their particular features, such as shallowness, relative isolation and protection from the sea, and the presence of boundaries with strong physical and ecological gradients help explain this high productivity. Despite the fact that coastal lagoons are among the most studied ecosystems in the world, our knowledge on fisheries in coastal lagoons or why some lagoons capable of maintaining profitable fisheries seem inadequate for intensive aquaculture remains limited. Scarce, too, is our knowledge of the characteristics of target species, their exploitation status, and the ecological processes that are affected by fisheries or that influence them, including the impact of human activities or climatic change. Here, we review present day knowledge on lagoon fisheries and analyse gaps in the science, stressing the need for adequate management of these important resources.

At the end of May, 17 scientists involved in an EU COST Action on Conservation Physiology of Marine Fishes met in Oristano, Sardinia, to discuss how physiology can be better used in modelling tools to aid in management of marine ecosystems. Current modelling approaches incorporate physiology to different extents, ranging from no explicit consideration to detailed physiological mechanisms, and across scales from a single fish to global fishery resources. Biologists from different sub-disciplines are collaborating to rise to the challenge of projecting future changes in distribution and productivity, assessing risks for local populations, or predicting and mitigating the spread of invasive species.

Anogramma leptophylla is one of few homosporous ferns with ephemeral sporophytes and perennial gametophytic tubercules. This rare aspect of the life cycle has considerable bearing on the reproductive features of the gametophyte. Four populations in the Iberian Peninsula were selected to provide spores for laboratory cultures and to sample natural populations of gametophytes for comparative studies. Sexual expression and the role of the tubercule in the reproductive biology of this fern were studied. No significant differences were found between percentages of sexual versus asexual prothalli in natural populations or laboratory cultures, or between percentages of unisexual and bisexual prothalli. These results may indicate that sex in A. leptophylla is genetically determined instead of environmentally controlled as in most ferns. The presence of a gametophytic tubercule with nutrient reserves seems to be most favourable for the development of archegonia, and for the establishment of young sporophytes. This...

Brackish water ecosystems are often exposed to wide variations in environmen-tal variables, including temperature and salinity, which may cause strong selec-tive pressures on organisms modifying the genetic patterns of species. The aimof this work was to test whether there is a ‘divergence-with-gene flow’ incoastal lagoon populations of white seabream (Diplodus sargus) (Ria Formosa,S Portugal and Mar Menor, SE Spain) respect to four marine populations, byusing partial sequences of cyt b mitochondrial gene and information from ninemicrosatellite loci. Genetic diversity was highest in both coastal lagoons (MarMenor and Ria Formosa) considering mitochondrial and nuclear markers.Although some of F ST population pairwise comparisons were not significant,analyses of molecular variance (AMOVAs) detected differences between groups(coastal lagoon and marine) close to significance. Also, only two haplotypes(Cytb-17 and Cytb-18) were detected in both coastal lagoon sampling sites andthese localities (Mar Menor and Ria Formosa) showed the highest number ofsingletons, some of them with a high number of mutations, as has been alreadydescribed for other Mar Menor populations (Pomatochistus marmoratus andHolothuria polii). Also, several tests detected significant positive and balancingselection considering mtDNA and microsatellite data. These data support thehypothesis of selection as one of the drivers of the genetic differences foundbetween coastal lagoon and marine populations. The life strategy adopted byDiplodus sargus in coastal lagoons allows it to decrease its mortality rate andimprove the heritability of its genes. Also, the increase time spent in coastallagoons with different temperatures and salinities favours the fitness selectionand the maintenance of exclusive haplotypes and genotypes in coastal lagooninhabitants favouring the ‘divergence-with-gene-flow’.

We assessed the genetic structure of populations of the widely distributed sea cucumber Holothuria (Holothuria) mammata Grube, 1840, and investigated the effects of marine barriers to gene flow and historical processes. Several potential genetic breaks were considered, which would separate the Atlantic and Mediterranean basins, the isolated Macaronesian Islands from the other locations analysed, and the Western Mediterranean and Aegean Sea (Eastern Mediterranean). We analysed mitochondrial 16S and COI gene sequences from 177 individuals from four Atlantic locations and four Mediterranean locations. Haplotype diversity was high (H = 0.9307 for 16S and 0.9203 for COI), and the haplotypes were closely related (π = 0.0058 for 16S and 0.0071 for COI). The lowest genetic diversities were found in the Aegean Sea population. Our results showed that the COI gene was more variable and more useful for the detection of population structure than the 16S gene. The distribution of mtDNA haplotypes, the pairwise FST values and the results of exact tests and amova revealed: (i) a significant genetic break between the population in the Aegean Sea and those in the other locations, as supported by both mitochondrial genes, and (ii) weak differentiation of the Canary and Azores Islands from the other populations; however, the populations from the Macaronesian Islands, Algarve and West Mediterranean could be considered to be a panmictic metapopulation. Isolation by distance was not identified in H. (H.) mammata. Historical events behind the observed findings, together with the current oceanographic patterns, were proposed and discussed as the main factors that determine the population structure and genetic signature of H. (H.) mammata.