Mediterranean Marine Biodiversity Research Articles

Review of Potential Effects of Oil Spills on Coastal and Marine Resources on Western Libyan Coastal

An oil spill can significantly affect coastal resources and the economy through economic activities that depend on clean seawater, coastal areas, and tourist sites, which may cause substantial economic losses after oil spills. However, this effect usually depends on the volume and type of oil spill and how sensitive it is to coastal and marine resources. Libya has one of the important Mediterranean marine biodiversity hotspots, which is the western Libyan coast that extends from western Tripoli city to the Gulf of Gabes with Tunisia. This work considers some of the effects of oil spills on a variety of coastal industries and social activities. In addition, this work provides a systematic literature review of biological, economic, and cultural resources and their sensitivity to oil spill scenarios on this coast. The findings of this work help provide a basis for the definition of priorities for protection to develop the capacity to respond to oil spills on the Libyan coast.

Variation and Diagnostic Power of the Internal Transcribed Spacer 2 in Mediterranean and Atlantic Eolid Nudibranchs (Mollusca, Gastropoda)

Mediterranean marine biodiversity is still underestimated especially for groups such as nudibranchs. The identification of nudibranchs taxa is challenging because few morphological characters are available and among them chromatic patterns often do not align with species delimitation. Molecular assessments helped unveiling cryptic diversity within nudibranchs and have been mostly based on mitochondrial markers. Fast evolving nuclear markers are much needed to complement phylogenetic and systematic assessments at the species and genus levels. Here, we assess the utility of the nuclear Internal Transcribed Spacer 2 (ITS2) to delimit species in the eolid nudibranchs using both primary and secondary structures. Comparisons between the variation observed at the ITS2 and at the two commonly used mitochondrial markers (COI and 16S) on 14 eolid taxa from 10 genera demonstrate the ability of ITS2 to detect congeneric, closely related, species. While ITS2 has been fruitfully used in several other mollusc taxa, this study represents the first application of this nuclear marker in nudibranchs.

Capturing the big picture of Mediterranean marine biodiversity with an end-to-end model of climate and fishing impacts

The Mediterranean Sea is one of the main hotspots of marine biodiversity in the world. The combined pressures of fishing activity and climate change have also made it a hotspot of global change amidst increasing concern about the worsening status of exploited marine species. To anticipate the impacts of global changes in the Mediterranean Sea, more integrated modelling approaches are needed, which can then help policymakers prioritize management actions and formulate strategies to mitigate impacts and adapt to changes. The aim of this study was to develop a holistic model of marine biodiversity in the Mediterranean Sea with an explicit representation of the spatial, multispecies dynamics of exploited resources subject to the combined influence of climate variability and fishing pressure. To this end, we used the individual-based OSMOSE model (Object-oriented Simulator of Marine ecOSystEms), including 100 marine species (fish, cephalopods and crustaceans) representing about 95% of the total declared catch, at a high spatial resolution (400 km2) and a large spatial scale (the entire Mediterranean basin) – the first time such a resolution and scale have been modelled. We then combined OSMOSE with the NEMOMED 12 physical model and the Eco3M-S biogeochemical low trophic level model to build the end-to-end model, OSMOSE-MED. We fitted OSMOSE-MED model with observed or estimated biomass and commercial catch data using a likelihood approach and an evolutionary optimization algorithm. The outputs of OSMOSE-MED were then verified against observed biomass and catch data, and compared with independent datasets (MEDITS data, diet composition and trophic levels). The model results – at different hierarchical levels, from individuals to the scale of the ecosystem – were consistent with current knowledge of the structure, functioning and dynamics of the ecosystems in the Mediterranean Sea. While the model could be further improved in future iterations, all the modelling steps – the comprehensive representation of key ecological processes and feedback, the selective parameterization of the model, and the comparison with observed data in the validation process – strengthened the predictive performance of OSMOSE-MED and thus its relevance as an impact model to explore the future of marine biodiversity under scenarios of global change. It is a promising tool to support ecosystem-based fishery management in the Mediterranean Sea.

Non-indigenous marine species in the Mediterranean Sea—Myth and reality

The spread of non-indigenous species is a global phenomenon that affects most ecosystems. Although invasion biology is a well-investigated discipline, there are still gaps in knowledge that may prevent obtaining a complete and realistic picture of the impact and scale of biological invasions. It is important, indeed, to distinguish between knowledge (reality) and what is taken for granted (myth). This study focused on the state of knowledge regarding the non-indigenous marine species currently present in the Mediterranean Sea. On the one hand, the information is overall exhaustive as regards the total number of non-indigenous species, their traits, invasiveness potential and vectors of spread. In particular, the Mediterranean is one of the best-monitored seas thanks to the international networks of marine scientists. On the other hand, however, scientific evidence does not suffice to draw general conclusions on the real magnitude of the ecological impact of non-indigenous species. Most studies, indeed, have investigated very few invasive species, generally at local scale, while the long-term effects of non-indigenous species are poorly known. The myth does not consist in stating that there is an ecological impact on Mediterranean marine biodiversity but in taking for granted that we are currently able to assess the magnitude of this impact. These uncertainties have inevitable consequences at decision-making and management level that could be mitigated through open interaction between stakeholders involved in policy and science on the one hand, and society on the other hand.

Application of the ecosystem service concept at a small-scale: The cases of coralligenous habitats in the North-western Mediterranean Sea

The understanding of ecosystem services is essential to support sustainable use and preservation of ecosystems. Coralligenous habitats, main contributors of the Mediterranean marine biodiversity, are yet understudied in term of services provided. This study presents an original small-scale approach to investigate the services provided by coralligenous habitats of a French study area consisting of two marine sites (Marseille and Port-Cros sites) in order to cover two contrasted anthropogenic pressure despite the small-scale. Our results are based on the opinions of 43 experts who ranked 15 services in terms of existence and level of importance for human well-being: supporting ecological functions were considered the most important, then provisioning and cultural services. Regulating services were considered uncertain due to a lack of knowledge. The small-scale approach highlighted a need for a referential frame to determine the existence of services (e.g. geographical and temporal scales, benefits and beneficiaries levels).

Fast-spreading green beds of recently introduced Halimeda incrassata invade Mallorca island (NW Mediterranean Sea)

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 558:153-158 (2016) - DOI: https://doi.org/10.3354/meps11869 NOTE Fast-spreading green beds of recently introduced Halimeda incrassata invade Mallorca island (NW Mediterranean Sea) Josep Alós1,2,*, Fiona Tomas1,3, Jorge Terrados1, Heroen Verbruggen4, Enric Ballesteros5 1Instituto Mediterráneo de Estudios Avanzados, IMEDEA (CSIC-UIB). C/ Miquel Marqués 21, 07190, Esporles, Illes Balears, Spain 2Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany 3Department of Fisheries and Wildlife, Oregon State University, OR, USA 4School of BioSciences, University of Melbourne, Victoria 3010, Australia 5Centre d’Estudis Avançats de Blanes (CEAB-CSIC), C/ Accés Cala Sant Francesc 14, 17300, Girona, Spain *Corresponding author: alos@imedea.uib-csic.es ABSTRACT: Mediterranean marine biodiversity is undergoing a tropicalization process. We present the first record and spread dynamics of the tropical green seaweed Halimeda incrassata (Bryopsidales, Chlorophyta) from the Mediterranean Sea. Plants were observed at 2 sites off Mallorca island (NW Mediterranean), and species identification was confirmed molecularly. Since the first observation of this alien seaweed in 2011, it has spread rapidly in the shallow subtidal habitat of a marine protected area located in Palma Bay, which has a depth of up to ca. 20 m. By 2015, this species spread by a factor of 6.75 and extended to an area of 2.7 km2, covering a total of 41% of the monitored area. The dynamics of the invasion suggest rapid colonization and establishment and spreading of the species through shallow sedimentary and rocky habitats. H. incrassata has the potential to strongly alter the ecosystem services and functioning of shallow Mediterranean habitats. We encourage authorities to pay attention to the spread of this alien seaweed at larger scales and determine the positive and negative effects of the invasion in order to facilitate research-driven decision making. KEY WORDS: Alien species · Fisheries · Mediterranean Sea · Tropicalization · Sediments · tufA gene Full text in pdf format Supplementary material PreviousNextCite this article as: Alós J, Tomas F, Terrados J, Verbruggen H, Ballesteros E (2016) Fast-spreading green beds of recently introduced Halimeda incrassata invade Mallorca island (NW Mediterranean Sea). Mar Ecol Prog Ser 558:153-158. https://doi.org/10.3354/meps11869 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 558. Online publication date: October 25, 2016 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2016 Inter-Research.

Mediterranean marine biodiversity under threat: Reviewing influence of marine litter on species

The Mediterranean Sea is one of the most polluted seas worldwide, especially with regard to plastics. The presence of this emerging man made contaminant in marine environments precludes large effects and interactions with species exposed to massive litter quantities. In this review, available data of floating and seafloor litter around Mediterranean sub-basins are reported. A review of scientific literature on the interaction of plastic with marine biota resulted in the identification of 134 species, several taxa and feeding strategies affected from 1986 to 2014. Data from 17,334 individuals showed different levels of ingestion and effects on catalogued IUCN species (marine mammals and sea turtles) in addition to several pelagic fish and elasmobranchs. Biodiversity is certainly under threat, and knowledge of the extent of taxa affected is of concern considering the increasing plastic loads in the Mediterranean Sea and worldwide.

Impacts of climate change on coastal benthic ecosystems: assessing the current risk of mortality outbreaks associated with thermal stress in NW Mediterranean coastal areas

In the framework of climate change, the increase in ocean heat wave frequency is expected to impact marine life. Large-scale positive temperature anomalies already occurred in the northwestern Mediterranean Sea in 1999, 2003 and 2006. These anomalies were associated with mass mortality events of macrobenthic species in coastal areas (0–40 m in depth). The anomalies were particularly severe in 1999 and 2003 when thousands of kilometres of coasts and about 30 species were affected. The aim of this study was to develop a methodology to assess the current risk of mass mortality associated with temperature increase along NW Mediterranean continental coasts. A 3D regional ocean model was used to obtain the temperature conditions for the period 2001–2010, for which the model outputs were validated by comparing them with in situ observations in affected areas. The model was globally satisfactory, although extremes were underestimated and required correction. Combined with information on the thermo-tolerance of a key species (the red gorgonian P. clavata) as well as its spatial distribution, the modelled temperature conditions were then used to assess the risk of mass mortality associated with thermal stress for the first time. Most of the known areas of observed mass mortality were found using the model, although the degree of risk in certain areas was underestimated. Using climatic IPCC scenarios, the methodology could be applied to explore the impacts of expected climate change in the NW Mediterranean. This is a key issue for the development of sound management and conservation plans to protect Mediterranean marine biodiversity in the face of climate change.

New Mediterranean Marine biodiversity records (December, 2013)

Based on recent biodiversity studies carried out in different parts of the Mediterranean, the following 19 species are included as new records on the floral or faunal lists of the relevant ecosystems: the green algae Penicillus capitatus (Maltese waters); the nemertean Amphiporus allucens (Iberian Peninsula, Spain); the salp Salpa maxima (Syria); the opistobranchs Felimida britoi and Berghia coerulescens (Aegean Sea, Greece); the dusky shark Carcharhinus obscurus (central-west Mediterranean and Ionian Sea, Italy); Randall’s threadfin bream Nemipterus randalli, the broadbanded cardinalfish Apogon fasciatus and the goby Gobius kolombatovici (Aegean Sea, Turkey); the reticulated leatherjack Stephanolepis diaspros and the halacarid Agaue chevreuxi (Sea of Marmara, Turkey); the slimy liagora Ganonema farinosum, the yellowstripe barracuda Sphyraena chrysotaenia, the rayed pearl oyster Pinctada imbricata radiata and the Persian conch Conomurex persicus (south-eastern Crete, Greece); the blenny Microlipophrys dalmatinus and the bastard grunt Pomadasys incisus (Ionian Sea, Italy); the brown shrimp Farfantepenaeus aztecus (north-eastern Levant, Turkey); the blue-crab Callinectes sapidus (Corfu, Ionian Sea, Greece). In addition, the findings of the following rare species improve currently available biogeographical knowledge: the oceanic pufferfish Lagocephalus lagocephalus (Malta); the yellow sea chub Kyphosus incisor (Almuñécar coast of Spain); the basking shark Cetorhinus maximus and the shortfin mako Isurus oxyrinchus (north-eastern Levant, Turkey).

Biogeographical homogeneity in the eastern Mediterranean Sea. II. Temporal variation in Lebanese bivalve biota

Lebanon (eastern Mediterranean Sea) is an area of particular biogeographic signifi- cance for studying the structure of eastern Mediterranean marine biodiversity and its recent changes. Based on literature records and original samples, we review here the knowledge of the Lebanese marine bivalve biota, tracing its changes during the last 170 yr. The updated checklist of bivalves of Lebanon yielded a total of 114 species (96 native and 18 alien taxa), accounting for ca. 26.5% of the known Mediterranean Bivalvia and thus representing a particularly poor fauna. Analysis of the 21 taxa historically described on Lebanese material only yielded 2 available names. Records of 24 species are new for the Lebanese fauna, and Lioberus ligneus is also a new record for the Mediterranean Sea. Comparisons between molluscan records by past (before 1950) and modern (after 1950) authors revealed temporal variations and qualitative modifications of the Lebanese bivalve fauna, mostly affected by the introduction of Erythraean species. The rate of recording of new alien species (evaluated in decades) revealed later first local arrivals (after 1900) than those observed for other eastern Mediterranean shores, while the peak in records in conjunc- tion with our samplings (1991 to 2010) emphasizes the need for increased field work to monitor their arrival and establishment. Finally, the scarce presence (or total absence) in the most recent samples of some once common habitat-forming species, as well as of some other native taxa, con- firmed their recent rarefaction (or local extinction), possibly related to their replacement by the aliens Brachidontes pharaonis, Spondylus spinosus and Chama pacifica.

Wrecks on the Bottom: Useful, Ecological Sentinels?

AbstractWrecks play an important role in enhancing marine biodiversity. SCUBA diving video-samplings were performed on eight wrecks, including seven shipwrecks and a sunken airplane, scattered over 180 km along the Ligurian coastline in the northwestern Mediterranean Sea, in water depths of 30‐65 m. Differences in composition of macrobenthic communities were found to be related to the bottom sedimentology and the composition and geometry of the investigated structures. The iron, flat, and even substrata of shipwrecks were dominated by Bivalvia (Ostrea edulis) and Anthozoa (Corynactis viridis), whereas the aluminum, cage-like structure of the airplane was dominated by massive sponges and bryozoans. Furthermore, abundances of some macrobenthic invertebrates were greater on the wrecks than those observed on natural, rocky substrates. Because of the increasing popularity of use of video and photo digital apparatuses among recreational divers, combined with wreck resistance to corrosion, artificial geometries and available surfaces that facilitate species’ settlement and growth, data from wrecks consisting of images and related metadata (depth, date, water temperature, etc.) could provide a new opportunity for monitoring Mediterranean marine biodiversity.

New Mediterranean Marine biodiversity records (June 2013)

This paper concerns records of species that have extended their distribution in the Mediterranean Sea. The finding of the rare brackish angiosperm Althenia filiformis in the island of Cyprus is interesting since its insertion in the Red Data Book of the Flora of Cyprus is suggested. The following species enriched the flora or fauna lists of the relevant countries: the red alga Sebdenia dichotoma (Greece), the hydrachnid mite Pontarachna adriatica (Slovenia), and the thalassinid Gebiacantha talismani (Turkey). Several alien species were recorded in new Mediterranean localities. The record of the burrowing goby Trypauchen vagina in the North Levantine Sea (Turkish coast), suggests the start of spreading of this Lessepsian immigrant in the Mediterranean Sea. The findings of the following species indicate the extension of their occurrence in the Mediterranean Sea: the foraminifer Amphistegina lobifera (island of Zakynthos, Greece), the medusa Cassiopea andromeda (Syria), the copepod Centropages furcatus (Aegean Sea), the decapod shrimp Melicertus hathor (island of Kastellorizo, Greece), the crab Menoethius monoceros (Gulf of Tunis), the barnacles Balanus trigonus, Megabalanus tintinnabulum, Megabalanus coccopoma and the bivalves Chama asperella, Cucurbitula cymbium (Saronikos Gulf, Greece).

Protecting Persistent Dynamic Oceanographic Features: Transboundary Conservation Efforts Are Needed for the Critically Endangered Balearic Shearwater

The protection of key areas for biodiversity at sea is not as widespread as on land and research investment is necessary to identify biodiversity hotspots in the open ocean. Spatially explicit conservation measures such as the creation of representative networks of marine protected areas (MPAs) is a critical step towards the conservation and management of marine ecosystems, as well as to improve public awareness. Conservation efforts in ecologically rich and threatened ecosystems are specially needed. This is particularly urgent for the Mediterranean marine biodiversity, which includes highly mobile marine vertebrates. Here, we studied the at sea distribution of one of the most endangered Mediterranean seabird, the critically endangered Balearic shearwater Puffinus mauretanicus. Present knowledge, from vessel-based surveys, suggests that this species has a coastal distribution over the productive Iberian shelf in relation to the distribution of their main prey, small pelagic fish. We used miniaturised satellite transmitters to determine the key marine areas of the southern population of Balearic shearwaters breeding on Eivissa and spot the spatial connections between breeding and key marine areas. Our tracking study indicates that Balearic shearwaters do not only forage along the Iberian continental shelf but also in more distant marine areas along the North African coast, in particular W of Algeria, but also NE coast of Morocco. Birds recurrently visit these shelf areas at the end of the breeding season. Species distribution modelling identified chlorophyll a as the most important environmental variable in defining those oceanographic features characterizing their key habitats in the western Mediterranean. We identified persistent oceanographic features across time series available in the study area and discuss our results within the current conservation scenario in relation to the ecology of the species.

Temperature Anomalies and Mortality Events in Marine Communities: Insights on Factors behind Differential Mortality Impacts in the NW Mediterranean

Two large-scale mass mortality events (MMEs) of unprecedented extent and severity affecting rocky benthic communities occurred during the summers of 1999 and 2003 along the coasts of the NW Mediterranean Sea. These mortality outbreaks were associated with positive thermal anomalies. In this study, we performed an analysis of inter-regional and inter-annual differences in temperature (T) conditions associated with MMEs of the red gorgonian Paramuricea clavata by analyzing high resolution T time series (hourly records for 3 to 8 years) from four regions of the NW Mediterranean with differing hydrological conditions and biological impacts. High resolution records allowed a detailed analysis using classical and new descriptors to characterize T anomalies. We were able to determine that the MMEs were triggered by two main types of positive thermal anomalies, with the first type being characterized by short periods (2 to 5 days) with high Mean T reaching more than 27°C in some regions and being associated with high intra-day and intra-period variability, while the second type of anomaly presented long duration (near one month) at warm T (24°C) with low intra-period variability. Inter-regional patterns arose; some regions displayed both types of anomalies, while others exhibited only one type. The results showed that T conditions should be considered as the main factor that explains the observed inter-regional and inter-annual differences in mortality impacts. In explaining these differences, the late timing of T anomalies, in addition to their magnitude was found to be determinant. Finally, by combining thermotolerance experimental data with the maximal T stress conditions observed in the four regions, we were able to determine the differential risk of mass mortality across regions. We conclude that expanding high resolution T series is important for the development of sound management and conservation plans to protect Mediterranean marine biodiversity in the face of climate change.

Human health benefits supplied by Mediterranean marine biodiversity

This paper summarizes the overall benefits supplied by Mediterranean marine biodiversity to human health and highlights the anthropogenic and environmental causes that are threatening these benefits. First, the Mediterranean Sea is a valuable source of seafood, which is an important component of the so-called “Mediterranean diet”. This type of diet has several health benefits, including cardio and cancer protective effects, which are attributed to the high intake of seafood-derived n-3 (omega-3) fatty acids. Second, the Mediterranean marine organisms, particularly the benthic ones, have furnished a large variety of bioactive metabolites, some of which are being developed into new drugs to threat major human diseases such as cancer. Third, the Mediterranean coastal areas provide environments for practising maritime leisure activities that provide physical and psychological benefits to users. Despite all this, fishing, tourism, contamination and sea warming are deteriorating this rich marine ecosystem, which needs to be protected to assure human welfare.

Inferred level of calcification decreases along an increasing temperature gradient in a Mediterranean endemic coral

The correlation between solar radiation and sea surface temperature (SST) and growth was assessed along a latitudinal gradient. Extension rate and skeletal density were both correlated with calcification rate, indicating that calcium carbonate deposition was allocated evenly between skeletal density and linear extension. Unlike most studies on other tropical and temperate corals, in which calcification was positively correlated with solar radiation and SST, in the present study calcification was not correlated with solar radiation, whereas it was negatively correlated with SST. We hypothesize that photosynthesis of the symbiotic algae of Balanophyllia europaea is inhibited at high temperatures, consequently causing an inhibition of calcification. The regressions between calcification and SST predicted that the calcification of B. europaea would be depressed at 20.5–21.0°C mean annual SST. The scenarios of the Intergovernmental Panel on Climate Change conclude that by 2100, SST will exceed this physiological threshold for most of the populations considered in this study. This study comprises the first field investigation of the relationships between environmental parameters and calcification of a Mediterranean coral and highlights the risks of losing Mediterranean marine biodiversity over the course of future decades.

Regional warming‐induced species shift in north‐west Mediterranean marine caves

AbstractThe north‐western Mediterranean Sea's high biodiversity originates from a mixture of temperate and subtropical species. Large‐scale warming has been detected through northward range shifts of ‘warm‐water’ species, and mass‐mortality events for ‘cold‐water’ invertebrates. Marine caves are affected in a more subtle way. By monitoring endemic species of cave mysids (Crustacea) and comparing our results with data in the literature, we observed a strong decline in one species, coupled with the success of another. Near Marseille (France), this phenomenon began while two major thermal anomalies were reported. Different tolerances to temperature were demonstrated by both the species distribution ranges and laboratory experimentation. We provide a possible physiological explanation for populations of cold stenothermal species of endemic cave mysids being replaced by congeners of warmer affinities, with a high risk of extinction. We also found strong support for the view that Mediterranean marine biodiversity is already under the threat of global warming.

Marine Biodiversity of the Mediterranean Sea: Situation, Problems and Prospects for Future Research

Mediterranean marine biodiversity has received only a fraction of the attention accorded to its terrestrial counterpart, despite the great cultural and economic importance that the sea has been having for the Mediterranean countries. A rough estimate of more than 8500 species of macroscopic marine organisms should live in the Mediterranean Sea, corresponding to somewhat between 4% and 18% of the world marine species. This is a conspicuous figure if one considers that the Mediterranean Sea is only 0.82% in surface area and 0.32% in volume as compared to the world ocean. The high biodiversity of the Mediterranean Sea may be explained by historical (its tradition of study dates older than for almost any other sea), paleogeographic (its tormented geological history through the last 5 my has been determining the occurrence of distinct biogeographic categories), and ecological (its variety of climatic and hydrologic situations within a single basin has probably no equals in the world) reasons. Present-day Mediterranean biodiversity is undergoing rapid alteration under the combined pressure of climate change and human impact, but protection measures, either for species or ecosystems, are still scarce. To understand the role and patterns of Mediterranean marine biodiversity, marine ecological research should: first, re-value those scientific areas currently unfashionable with funding agencies (systematics, biogeography and taxonomy); second, start monitoring biodiversity with a long-term approach at a whole Mediterranean scale, possibly through an internationally co-ordinated network of marine protected areas.