Marine Research Findings of the VECTORS Project

This website provides access to the research results of the VECTORS project, which can be used to support marine management decisions, policies and governance as well as future research and investment. VECTORS was a large scale project that brought together more than 200 expert researchers from 16 different countries. It examined the significant changes taking place in European seas, their causes, and the impacts they will have on society.

Publications

All of the publications created as part of the VECTORS project are listed below (latest first).
Please use the search box below to find a publication by title, author(s), year or keyword; the most relevant results will be displayed at the top of the page.

  • Fauser, P., H. Sanderson, R.V. Hedegaard, J.J. Sloth, M.M. Larsen, T. Krongaard, R. Bossi and J.B. Larsen. (2012). Occurrence and sorption properties of arsenicals in marine sediments. Environmental Monitoring and Assessment 185(6), 4679-4691. doi:10.1007/s10661-012-2896-2 http://dx.doi.org/10.1007/s10661-012-2896-2
    View abstract The content of total arsenic, the inorganic forms: arsenite (As(III)) and arsenate (As(V)), the methylated forms: monomethylarsonic acid and dimethylarsinic acid (DMA), trimethylarsenic oxide, tetramethylarsenonium ion and arsenobetaine was measured in 95 sediment samples and 11 pore water samples from the Baltic Sea near the island of Bornholm at depths of up to 100 m. As(III+V) and DMA were detected in the sediment and As(III+V) was detected in the sediment pore water. Average total As concentration of 10.6±7.4 mg/kg dry matter (DM) in the sediment corresponds to previously reported values in the Baltic Sea and other parts of theworld. Existing data for on-site measurements of sorption coefficients (Kd) of arsenicals in marine and freshwater sediments show large variability from <1 to >1,000 L/kg. In this work, calculated sorption coefficients (Kd and Koc) for As(III+V) showed significant correlation with depth, dissolved oxygen (DO), salinity and sediment classification; for depths <70 m, salinity <11 %, DO >9 mg/L and sand/silt/clay sediments the Kd was 118±76 L/kg DM and for depths >70 m, salinity >11 %, DO<9 mg/L and muddy sediments the Kd was 513±233 L/kg DM. The authors recommend using the found Kd value for arsenic in marine sediments when conditions are similar to the Baltic Sea. At locations with significant anthropogenic point sources or where the local geology contains volcanic rock and sulphide mineral deposits, there may be significantly elevated arsenic concentrations, and it is recommended to determine on-site Kd values.
  • Teal, L.R., R. Van Hal, T. Van Kooten, P. Ruardij and A.D. Rijnsdorp. (2012). Bio-energetics underpins the spatial response of North Sea plaice (Pleuronectes platessa L.) and sole (Solea solea L.) to climate change. Global Change Biology 18(11), 3291-3305. doi:10.1111/j.1365-2486.2012.02795.x http://dx.doi.org/10.1111/j.1365-2486.2012.02795.x
    View abstract Climate change is currently one of the main driving forces behind changes in species distributions, and understanding the mechanisms that underpin macroecological patterns is necessary for a more predictive science. Warming sea water temperatures are expected to drive changes in ectothermic marine species ranges due to their thermal tolerance levels. Here, we develop a mechanistic tool to predict size- and season-specific distributions based on the physiology of the species and the temperature and food conditions in the sea. The effects of climate conditions on physiological based habitat utilization was then examined for different size-classes of two commercially important fish species in the North Sea, plaice, Pleuronectes platessa, and sole, Solea solea. The two species provide an attractive comparison as they differ in their physiology (e.g. preferred temperature range). Combining dynamic energy budget (DEB) models with the temperature and food conditions estimated by an ecosystem model (ERSEM), allowed spatial differences in potential growth (as a proxy for habitat quality) to be estimated for 2 years with contrasting temperature and food conditions. The resulting habitat quality maps were in broad agreement with observed ontogenetic and seasonal changes in distribution as well as with the recent changes in distribution which could be attributed to an increase in coastal temperatures. Our physiological-based model provides a powerful tool to explore the effect of climate change on the spatio-temporal fish dynamics, predict effects of local or broad-scale environmental changes and provide a physiological basis for observed changes in species distributions.
  • Terlizzi, A., P. Tedesco and P.P. Patamello. (2012). Spread of pathogens from marine cage aquaculture: a potential threat for wild fish assemblages under protection regimes? In: B. Yoğurtçuoğlu, editor. Aquaculture. InTech Publishing.http://dx.doi.org/10.5772/30826
    View abstract The spread and the control of pathogens represent a serious problem in aquaculture, implying important environmental and economic issues (Huntington, 2006; Sapkota et al., 2008). With the rapid development of aquaculture in recent decades (Food and Agriculture Organization [FAO], 2008), an increasing number of pathogens involved in fish disease, and the range of susceptible fish species have been identified and described. The increasing use of molecular tools has helped improve our knowledge in this area. Few studies have been performed to evaluate the interactions host/pathogen in the natural environment (Hedrick, 1998), or to investigate the mechanisms of infection and interaction between farmed and wild specimens, nor the ecological role assumed by infected wild hosts has been explored yet. In view of the current decline of fish stocks, which has recently been attributed not only to habitat loss and overfishing, but also even to the spread of pathogens (Daszak, 2000; Gozlan et al., 2005), understanding these mechanisms
  • Thomsen, M.S., T. Wernberg, A.H. Engelen, F. Tuya, M.A. Vanderklift, M. Holmer, K.J. McGlathery, F. Arenas, J. Kotta and B.R. Silliman. (2012). A meta-analysis of seaweed impacts on seagrasses: generalities and knowledge gaps. Plos One 7(1), e28595. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0028595
    View abstract Seagrasses are important habitat-formers and ecosystem engineers that are under threat from bloom-forming seaweeds. These seaweeds have been suggested to outcompete the seagrasses, particularly when facilitated by eutrophication, causing regime shifts where green meadows and clear waters are replaced with unstable sediments, turbid waters, hypoxia, and poor habitat conditions for fishes and invertebrates. Understanding the situations under which seaweeds impact seagrasses on local patch scales can help proactive management and prevent losses at greater scales. Here, we provide a quantitative review of available published manipulative experiments (all conducted at the patch-scale), to test which attributes of seaweeds and seagrasses (e.g., their abundances, sizes, morphology, taxonomy, attachment type, or origin) influence impacts. Weighted and unweighted meta-analyses (Hedges d metric) of 59 experiments showed generally high variability in attribute-impact relationships. Our main significant findings were that (a) abundant seaweeds had stronger negative impacts on seagrasses than sparse seaweeds, (b) unattached and epiphytic seaweeds had stronger impacts than 'rooted' seaweeds, and (c) small seagrass species were more susceptible than larger species. Findings (a) and (c) were rather intuitive. It was more surprising that 'rooted' seaweeds had comparatively small impacts, particularly given that this category included the infamous invasive Caulerpa species. This result may reflect that seaweed biomass and/or shading and metabolic by-products like anoxia and sulphides could be lower for rooted seaweeds. In conclusion, our results represent simple and robust first-order generalities about seaweed impacts on seagrasses. This review also documented a limited number of primary studies. We therefore identified major knowledge gaps that need to be addressed before general predictive models on seaweed-seagrass interactions can be build, in order to effectively protect seagrass habitats from detrimental competition from seaweeds.
  • Minchin, D., A. Lodola and A. Occhipinti-Ambrogi. (2012). The occurrence of Caprella scaura (Amphipoda: Caprellidae) in marinas in Lanzarote island (Canary archipelago, Macaronesia). Marine Biodiversity Records 5. doi:10.1017/S175526721200098X http://dx.doi.org/10.1017/S175526721200098X
    View abstract Caprella scaura is thought to come from the western Indian Ocean and was first recorded in the Atlanto-Mediterranean region in the Lagoon of Venice in 1994. Since then the species has rapidly spread throughout the Mediterranean Sea and it has recently been reported in the eastern Atlantic Ocean. The occurrence of C. scaura in two marinas in Lanzarote, Canary Islands, is discussed taking into account the possible pathways of introduction. The most likely vector of introduction is within the hull-fouling community on recreational craft. It may be expected to appear in other marinas within Macaronesia.
  • Narščius, A., S. Olenin, A. Zaiko and D. Minchin. (2012). Biological invasion impact assessment system: From idea to implementation. Ecological Informatics 7, 46-51. http://www.sciencedirect.com/science/article/pii/S1574954111000938
    View abstract We describe the Biological Invasion Impact / Biopollution Assessment System (BINPAS), an online application for assessment of invasive species impacts. The methodology is based on a classification of the abundance and distribution range of alien species related to the magnitude of their impacts on communities, habitats and ecosystem functioning. Then formalized data is aggregated in a hybrid ranking and the system provides a "Biopollution Level" (BPL), ranging from "no measurable impact" (BPL=0) to "massive impact" (BPL=4). BINPAS was created using open source web technologies and relational database management systems. The system provides a user-friendly interface to calculate BPL, it allows for the sharing of ecological data, providing inter-regional comparisons and meta-analysis of biological invasion effects at different spatial and temporal scales.
  • Padedda, B.M., S. Pulina, P. Magni, N. Sechi and A. Lugliè. (2012). Phytoplankton dynamics in relation to environmental changes in a phytoplankton-dominated Mediterranean lagoon (Cabras Lagoon, Italy). Advances in Oceanography and Limnology 3(2), 147-169. doi:10.1080/19475721.2012.716792 http://dx.doi.org/10.1080/19475721.2012.716792
    View abstract In Mediterranean lagoons, macrophytes often surpass phytoplankton as the most important primary producers. Less frequently, phytoplankton dominates throughout the year, thus knowledge of its dynamics is relatively limited and scattered. In this study, we assessed over two years the dynamics of phytoplankton assemblages, including potential harmful algal species (HAS), in relation to environmental changes in the phytoplankton-dominated Cabras Lagoon (Sardinia, Italy). The lagoon was characterised by uniform spatial conditions, wide temporal variations in salinity (<3 to >40 PSU) and high nutrient availability. Phosphorus was highest in summer, possibly recycled within the system, while dissolved inorganic nitrogen increased in winter and spring due to watershed discharge. Chlorophyll a, positively correlated with nutrients and rainfall, showed a typical bimodal pattern with summer-winter blooms. Modifications in phytoplankton composition strongly correlated with extreme weather events, such as intense rainfall. This generated an abrupt salinity decrease that, combined with high nutrient availability, favoured the dominance of Cyanophyceae of reduced cell size, such as Cyanobium and Rhabdoderma species. We suggest that the prolonged and intense dominance of Cyanophyceae, added to other HAS, has a negative impact on the primary economic activities of the lagoon, such as fishery, and generally on the whole lagoon functioning.
  • Paganelli, D., A. Marchini and A. Occhipinti-Ambrogi. (2012). Functional structure of marine benthic assemblages using Biological Traits Analysis (BTA): A study along the Emilia-Romagna coastline (Italy, North-West Adriatic Sea). Estuarine, Coastal and Shelf Science 96, 245-256. http://www.sciencedirect.com/science/article/pii/S0272771411004653
    View abstract The functional diversity index has shown that the functional diversity of the macrobenthic community increased along a spatial gradient of distance from the Po river delta (Emilia-Romagna coast, Italy, North- Adriatic Sea), which suggests that riverine inputs have a detrimental effect on community functioning. This study focuses on two different depths along a southward gradient of increasing distance from the Po river delta where the Po river is the main source of freshwater and nutrient inputs in the North-Adriatic Sea. A Biological Traits Analysis (BTA) was used to examine a dataset of 156 soft-bottom macrobenthic species that were collected at eight stations in this area. Instead of comparing communities on the basis of their taxonomic composition, BTA uses a series of life history, morphological and behavioural characteristics of species to indicate aspects of their ecological functioning. The variability of the Emilia-Romagna dataset was governed by relatively few biological traits: growth form, trophic group, type of movement, habit, adult mobility and bioturbation activity. The community closer to the coastline was mainly composed of moderately mobile vermiform organisms with burrowing or tube-dwelling behaviour, and deposit feeding behaviour. However, the offshore community was mainly characterized by organisms with a laterally compressed or globose body and tube-dwelling behaviour; filter feeders and deposit feeders were dominant.
  • Stabili, L., F. Cardone, P. Alifano, S.M. Tredici, S. Piraino, G. Corriero and E. Gaino. (2012). Epidemic mortality of the sponge Ircinia variabilis (Schmidt, 1862) associated to proliferation of Vibrio bacterium. Microbial Ecology 64(3), 802-813. doi:10.1007/s00248-012-0068-0 http://dx.doi.org/10.1007/s00248-012-0068-0
    View abstract In recent years, several episodes of mass mortality of sessile epibenthic invertebrates, including sponges, have been recorded worldwide. In the present study, we report a disease event on Ircinia variabilis recorded in September 2009 along the southern Adriatic and Ionian seas (Apulian coast), with the aim to quantify the mortality incidence on the sponge population, to investigate the effect of the disease on the sponge tissues and to assess whether the disease is associated with vibrios proliferation. The injured sponges showed wide necrotic areas on the surface or disruption of the body in several portions. Necrotic areas were whitish and often were covered with a thin mucous coat formed by bacteria. In the most affected specimens, sponge organisation resulted partial or complete loss, with the final exposure of the dense skeletal network of spongine fibres to the environment. The results of microbiological cultural analysis using in parallel Marine Agar 2216 and thiosulphate/citrate/bile salts/sucrose agar demonstrated that, in affected specimens, vibrios represented 15.8 % of the total I. variabilis surface culturable bacteria. Moreover, all the isolated vibrios, grown from the wide whitish areas that characterize the surface of the diseased sponges, were identified, and their assignment to the Vibrio rotiferianus was consistent with phylogenetic analysis and data of morphological, cultural and biochemical tests. Studies on V. rotiferianus have shown that its pathogenicity, with respect to various aquatic organisms, is higher than that of Vibrio harveyi. The factors triggering the disease outbreak in Ircinia variabilis populations remain unclear. At present, we can hypothesize the involvement in the disease of a synergetic mechanism that, under stressful physiological conditions (high temperature, elevated nutrients and reduced water flow), induces sponge pathogens, in our case V. rotiferanius, to become virulent, making sponges unable to control their proliferation. Additional studies are needed to understand the etiological processes as well as the factors involved in sponges recovering from this epidemic event allowing them to face mass mortality. A drastic reduction of sponge-specific representatives could have marked a negative impact on the environmental health on account of their role in the sea remediation processes as filter-feeding organisms.
  • Tagliapietra, D., M. Sigovini and P. Magni. (2012). Saprobity: a unified view of benthic succession models for coastal lagoons. Hydrobiologia 686(1), 15-28. doi:10.1007/s10750-012-1001-8 http://dx.doi.org/10.1007/s10750-012-1001-8
    View abstract We briefly review and expand upon classic conceptual models describing the succession of benthic communities along a gradient of organic matter (OM) enrichment developed for freshwater (the Saprobity System), coastal marine (the Pearson-Rosenberg [P-R] model) and lagoon (the Gue'lorget- Perthuisot [G-P] model) ecosystems. Differences and similarities between various approaches and models are highlighted and the P-R and G-P models are unified under a single conceptual framework of habitat saprobity in coastal lagoons. We refer to saprobity as the state of an aquatic ecosystem resulting from the input and decomposition of OM and the removal of its catabolites. In addition to other factors, such as salinity, saprobity is viewed as a selection factor for species diversity. The higher the saprobity is, the more impaired the system is, with progressively poorer benthic communities characterized by species that are increasingly tolerant of reducing conditions and toxicity. In coastal lagoons, these processes are strongly driven by hydrodynamics, which govern the land-sea gradient. Based on our review and analysis, we find that saprobity can be a useful descriptor of ecosystem state as determined by OM metabolism, suitable for characterizing the natural conditions of coastal lagoons and assessing their quality.
  • Rochette, S., M. Huret, E. Rivot and O. Le Pape. (2012). Coupling hydrodynamic and individual-based models to simulate long-term larval supply to coastal nursery areas. Fisheries Oceanography 21(4), 229-242. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2419.2012.00621.x/abstract
    View abstract For many marine fish species, recruitment is strongly related to larval survival and dispersal to nursery areas. Simulating larval drift should help assessing the sensitivity of recruitment variability to early life history. An individual-based model (IBM) coupled to a hydrodynamic model was used to simulate common sole larval supply from spawning areas to coastal and estuarine nursery grounds at the population scale in the eastern Channel on a 14-yr time series, from 1991 to 2004. The IBM allowed each particle released to be transported by currents from the hydrodynamic model, to grow with temperature, to migrate vertically giving stage development, and possibly to die according to drift duration, representing the life history from spawning to metamorphosis. Despite sensitivity to the larval mortality rate, the model provided realistic simulations of cohort decline and spatio-temporal variability of larval supply. The model outputs were analysed to explore the effects of hydrodynamics and life history on the interannual variability of settled sole larvae in coastal nurseries. Different hypotheses of the spawning spatial distribution were also tested, comparing homogeneous egg distribution to observation and potential larval survival (PLS) maps. The sensitivity analyses demonstrated that larval supply is more sensitive to the life history along larval drift than to the phenology and volume of spawning, providing explanations for the lack of significant stock-recruitment relationship. Nevertheless, larval supply is sensitive to spawning distribution. Results also suggested a very low connectivity between supposed different sub-populations in the eastern Channel.
  • Peck, M.A., K.B. Huebert and J.K. Llopiz. (2012). Chapter 3 - Intrinsic and extrinsic factors driving match-mismatch dynamics during the early life history of marine fishes. In: G. Woodward, J. Ute and E. J. O'Gorman, editors. Advances in Ecological Research. Academic Press. p. 177-302.http://www.sciencedirect.com/science/article/pii/B978012398315200003X
    View abstract We review intrinsic traits of the early life stages of marine fishes to gain a better understanding of how climate-driven changes in abiotic (temperature) and biotic (match-mismatch dynamics with prey) factors may differ among taxonomic groups and/or habitats (from low to high latitudes). Intrinsic traits related to the thermal sensitivity of development of endogenously feeding life stages included the time required for eggs to hatch (58 species, 26 families), the size of larvae at hatch (31 spp., 15 families) and the time required for young larvae to deplete energy reserves (48 spp., 22 families). These intrinsic factors will influence spatiotemporal match-mismatch dynamics at first feeding, a critical period for growth and survival. In exogenously feeding larvae, key intrinsic traits reviewed included differences in early morphology and developmental trajectories (64 spp., 20 families) and the foraging ability of marine fish larvae. Routine and critical swimming speeds were 5-10 times higher in the larvae of species from low (tropical) versus higher (temperate/polar) latitudes. Based solely on routine metabolic losses (26 spp., 15 families), sevenfold increases in larval foraging requirements were estimated between 5 and 25°C to offset starvation. Finally, a thorough review of larval diets (57 spp., 20 families) found clear differences (particularly at first feeding) by taxon and habitat. Our review and synthesis highlights gaps in knowledge and recommends future research directions to stengthen how larval development, feeding, and growth are depicted within individual based models, which are useful tools for examining climate-driven processes affecting marine fishes and how intrinsic properties and extrinsic factors interact to influence survival. We argue that thorough, taxonomic and habitat-based comparisons of intrinsic properties of fish larvae are required to adequately project potential impacts of climate change on the distribution and productivity of marine fish species.
  • Peck, M.A. and M. Hufnagl. (2012). Can IBMs tell us why most larvae die in the sea? Model sensitivities and scenarios reveal research needs. Journal of Marine Systems 93(S1), 77-93. doi:10.1016/j.jmarsys.2011.08.005 http://dx.doi.org/10.1016/j.jmarsys.2011.08.005
    View abstract Biophysical individual-based models (IBMs) are the only tools that can provide estimates of spatial and temporal changes in mortality rates of marine fish early life stages as well as the various processes that contribute to those changes. Given the increasing use of these models, one must ask the question: How much faith can we have in their estimates? We briefly review mortality processes acting on marine fish early life stages and how IBMs have been used to estimate those processes. Next, we provide a summary of the sensitivity analyses and scenario results conducted in 50 studies that provided estimates of: 1) advection-based losses from drift modeling, 2) mortality due to starvation from foraging and growth modeling, and/or 3) modeled mortality due to predators. We illustrate how IBM estimates of larval distribution and survival can be sensitive to assumptions regarding the magnitude and timing of mortality by performing drift model simulations for Atlantic herring (Clupea harengus) larvae in the North Sea. Despite the growing number of studies applying IBMs, less than 25% reviewed here included formal sensitivity analyses of parameters. Our literature review indicated a need for biological research on 1) larval swimming behavior including cues for movements, 2) foraging parameters such as larval visual field estimates, and 3) parameters associated with growth physiology including assimilation efficiency and energy losses due to active metabolism. Ontogenetic changes in those factors are particularly relevant to examine for modeling activities. Methods also need to be developed for depicting predator encounter in a dynamic way (e.g., based upon predator-prey overlap). High priority should be given to developing (and funding) research programs that not only construct and apply IBMs but also that measure the aspects of larval behavior and physiology as well as aspects of the larval environment needed to parameterize them. Coupling these research activities will strengthen our confidence in IBM-derived estimates of mortality and the processes responsible for death of larvae in the sea.
  • Rilov, G., R.C. Mant, D.A. Lyons, F. Bulleri, L. Benedetti-Cecchi, J. Kotta, A.M. Queiros, E. Chatzinikolaou, T.P. Crowe and T. Guy-Haim. (2012). How strong is the effect of invasive ecosystem engineers on the distribution patterns of local species, the local and regional biodiversity and ecosystem functions? Environmental Evidence 1(1), 10. http://www.environmentalevidencejournal.org/content/1/1/10
    View abstract One of the most influential forms of biological invasions is that of invasive ecosystem engineers, species that affect other biota via alterations to the abiotic environment. Such species can have wide-reaching consequences because they alter ecosystems and essentially "change the rules of existence" for a broad suite of resident biota. They thus affect resources or stressors that affect other organisms.The objective of this systematic review will be to quantify the positive and negative impacts of invasive ecosystem engineers on ecosystem structure and functioning, and to identify factors that cause their effects to vary. We will search a number of online databases to gather empirical evidence from the literature on the impacts of invasive ecosystem engineers on: (1) species richness and other univariate and multivariate measures of biodiversity; (2) productivity and abundance of algae, and animals; and (3) biogeochemical cycling and other flows of energy and materials, including trophic interactions. Data from relevant studies will be extracted and used in a random effects meta-analysis in order to estimate the average effect size of invasive ecosystem engineers on each response of interest.
  • Rindorf, A. and P. Lewy. (2012). Estimating the relationship between abundance and distribution. Canadian Journal of Fisheries and Aquatic Science 69, 382-397. doi:doi:10.1139/F2011-153 http://dx.doi.org/10.1139/F2011-153
    View abstract Numerous studies investigate the relationship between abundance and distribution using indices reflecting one of the three aspects of distribution: proportion of area occupied, aggregation, and geographical range. Using simulations and analytical derivations, we examine whether these indices provide unbiased estimates of the relationship when estimated from count data. The indices investigated include the proportion of empty samples, the proportion of structurally empty samples, Lloyds index of patchiness, measures derived from Lorenz curves (such as D95 and the Gini index), and measures based on Euclidean distance to the centre of gravity of the spatial distribution. Only the proportion of structurally empty areas, Lloyds index, and indices of the distance to the centre of gravity of the spatial distribution are unbiased at all levels of abundance. The remaining indices generate relationships between abundance and distribution even in cases where no underlying relationships exists, although the problem decreases for measures derived from Lorenz curves when samples contain more than four individuals on average. To illustrate the problem, the indices are applied to juvenile North Sea cod, Gadus morhua.
  • Edelist, D., D. Golani, G. Rilov and E. Spanier. (2011). The invasive venomous striped eel catfish Plotosus lineatus in the Levant: possible mechanisms facilitating its rapid invasional success. Marine Biology 159(2), 283-290. doi:10.1007/s00227-011-1806-4 http://dx.doi.org/10.1007/s00227-011-1806-4
    View abstract The venomous striped eel catfish Plotosus lineatus was first recorded in the Mediterranean in 2002. Within 1-3 years, it has spread throughout the entire Israeli coast. We have studied its spatiotemporal distribution patterns via trawl surveys in order to determine the scale and extent of this invasion. Findings indicate that a population explosion has occurred, and the catfish now inhabits all sandy and muddy substrates up to ca 80 m. P. lineatus was found to recruit in autumn in the Mediterranean and displays similar or improved growth patterns and condition factor compared to those found in its native habitat. We discuss the possible ecological mechanisms responsible for its success: Benthic invaders are among its main prey items, suggesting an invasional meltdown process. We also point to the decline of indigenous species using its trophic and behavioral-ecological niche and hypothesize that they might be outcompeted and displaced by the catfish.
  • Edelist, D., O. Sonin, D. Golani, G. Rilov and E. Spanier. (2011). Spatio-temporal patterns of catch and discards of the Israeli Mediterranean trawl fishery in the early 1990s: ecological and conservation perspectives. Scientia Marina 75(4), 641-652. http://scientiamarina.revistas.csic.es/index.php/scientiamarina/article/view/1288/1365
    View abstract The spatiotemporal patterns of discards and catch composition of Israeli trawlers were examined using a 4-year (1990-1994), 324 haul dataset. Haul depth was found to be the main grouping variable for hauls, although significant seasonal differences were also found. 28.3% of the total catch was discarded, and there was a 40.1% discard percentage in shallow hauls. According to these figures, annual discards for the Israeli trawl fleet for the study period are estimated at ca. 440 to 700 t. Both the biomass and the number of discarded specimens peaked in summer, as well as the percentage of juvenile fish of commercial species. These findings suggest that a summer moratorium on trawling would reduce discards. The percentage of specimens of Indo-Pacific origin decreased from 51% in depths shallower than 37 m to 24% between 38 and 73 m, and 8% in deeper strata. Discards along the Israeli coast were comparable to those observed elsewhere in the Mediterranean. The findings presented here are the first quantitative account of fish community assemblages in the nearshore waters of the easternmost part of the Mediterranean, and thus provide valuable information for comparisons with more current datasets that are currently being assembled.
  • Galil, B.S., R. Gevili and T. Shiganova. (2011). Not far behind: First record of Beroe ovata Mayer, 1912 (Ctenophora: Beroida: Beroidae) off the Mediterranean coast of Israel. Aquatic Invasions 6(Supplement 1), S89-S90. http://www.aquaticinvasions.net/2011/Supplement/AI_2011_6_S1_Galil_etal.pdf
    View abstract The American brown comb jelly, Beroe ovata, was first noted off the Mediterranean coast of Israel on 10 June 2011, outside the port of Ashdod. The occurrence of B. ovata soon after its prey, Mnemiopsis leidyi, had been recorded follows the pattern of spread elsewhere, yet its presence in the warm and saline waters of the SE Levant is a surprise.
  • Gasith, A., S. Gafny, Y. Hershkovitz, H. Goldstein and B.S. Galil. (2011). The invasive freshwater medusa Craspedacusta sowerbii Lankester, 1880 (Hydrozoa: Olindiidae) in Israel. Aquatic Invasions 6(S1), 147-152. http://www.aquaticinvasions.net/2011/Supplement/AI_2011_6_S1_Gasith_etal.pdf
    View abstract The freshwater jellyfish Craspedacusta sowerbii, native to China, has been introduced to lentic and lotic habitats in artificial and natural bodies of water, in subtropical to temperate regions worldwide. In the Middle East it has been recorded from an artificial lake in the Nile Delta, Egypt, a recreational lake in Iraq, a reservoir and a dammed lake in Turkey. The first record in Israel dates back half a century - to an aquarium at the Hebrew University in Jerusalem. Since 2003 medusae of C. sowerbii have been observed in a perennial stream flowing into Sea of Galilee - Israel's principal freshwater storage and supply reservoir. The possible impacts of a substantial bloom are discussed.
  • Jaerv, L., J. Kotta, I. Kotta and T. Raid. (2011). Linking the structure of benthic invertebrate communities and the diet of native and invasive fish species in a brackish water ecosystem. Annales Zoologici Fennici 48(3), 129-141. http://www.sekj.org/AnnZool.html
    View abstract Recruitment variability of marine fish is influenced by the reproductive potential of the stock (i.e. stock characteristics and abundance) and the survival of early life stages, mediated by environmental conditions of both a physical (water temperature, salinity and oxygen conditions, ocean currents) and a biological nature (i.e. food, predators). The objective of this study is to assess the importance of variability in environmental conditions within different western Baltic cod spawning grounds for egg survival. Habitat identification was based on environmental threshold levels for egg survival and development and ambient hydrographical conditions at different times during the spawning season. The long-term resolution of environmental conditions allowing survival of western Baltic cod eggs indicates that favourable conditions predominantly occurred during the late spawning season in April/May, while minimum survival rates could be expected from January to March. Unsuitable time periods and habitats exhibiting the highest mortality rates are exclusively characterized by ambient water temperatures below the critical survival threshold. Despite the strong influence of water temperature on habitat suitability, the impact of habitat suitability on recruitment was not clearly defined, suggesting that other mechanisms regulate year class strength.
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