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.

  • Gueroun, S.K.M., O.K.-D. Yahia, A. Deidun, V. Fuentes, S. Piraino and M.N.D. Yahia. (2014). First record and potential trophic impact of Phyllorhiza punctata (Cnidaria: Scyphozoa) along the north Tunisian coast (South Western Mediterranean Sea). Italian Journal of Zoology. doi:10.1080/11250003.2014.981306 http://www.tandfonline.com/doi/full/10.1080/11250003.2014.981306#abstract
    View abstract The Australian spotted scyphomedusa Phyllorhiza punctata was recorded for the first time in Tunisian waters in August 2012, in the lagoon of Bizerte (Tunisia). Metaephyrae and juveniles occurred simultaneously in August 2012. The occurrence of adult medusae was detected from September to November 2012, and from August to October 2013. This is the second record of a reproducing population of P. punctata in the Mediterranean Sea. The low abundance of mesozooplankton in summer and autumn 2012 coincides temporally with the highest density of P. punctata recorded in the lagoon, suggesting that predation by this alien jellyfish may have been a limiting factor for the mesozooplankton abundance on site.
  • Isinibilir, M., L. Martell, E.N. Topçu, I.N. Yilmaz and S. Piraino. (2014). First inventory of the shallow-water benthic hydrozoan assemblages of Gökçeada Island (northern Aegean Sea). Italian Journal of Zoology. doi:10.1080/11250003.2014.977970 http://www.tandfonline.com/doi/full/10.1080/11250003.2014.977970#abstract
    View abstract The hydroid fauna of the Mediterranean Sea is considered one of the best known in the world, but the hydrozoans of the Aegean Sea remain poorly studied, hindering efforts to identify alien and invasive species in the region. The spatial and seasonal composition of the shallow-water (0–20 m depth) benthic hydrozoan assemblage from Gökçeada Island was investigated in summer 2012 and winter 2013. Overall, 48 hydrozoan taxa were identified, and their presence and ecological features are discussed herein. Twelve species are recorded for the first time in the Aegean Sea, and the same number for the Turkish coasts. Differences in species composition were detected between the northern and southern coasts of Gökçeada by cluster, multidimensional scaling (MDS) and permutational multivariate analysis of variance (PERMANOVA) analysis, whereas seasonal and vertical distribution patterns were not statistically significant. Differences in species richness and composition between the northern and southern coasts may be explained by the distinct geomorphological aspects of the shores, providing a spatial heterogeneity in the availability of substrates for the hydroid colonies. Observed differences are attributable to the occurrence and/or abundance of common species such as Sertularella ellisii, Aglaophenia tubiformis, Clytia hemisphaerica, Clytia linearis, Eudendrium racemosum, Plumularia obliqua, Eudendrium capillare, Turritopsis dorhnii and Dynamena disticha, rather than to the presence of rare, exclusive species
  • Wlodarska-Kowalczuk, M., E. Jankowska, L. Kotwichi and P. Balazy. (2014). Evidence of season-dependency in vegetation effects on macrofauna in temperate seagrass meadows (Baltic Sea). Plos One 9(7), e100788. doi:10.1371/journal.pone.0100788 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0100788
    View abstract Seagrasses and associated macrophytes are important components of coastal systems as ecosystem engineers, habitat formers, and providers of food and shelter for other organisms. The positive impacts of seagrass vegetation on zoobenthic abundance and diversity (as compared to bare sands) are well documented, but only in surveys performed in summer, which is the season of maximum canopy development. Here we present the results of the first study of the relationship between the seasonal variability of seagrass vegetation and persistence and magnitude of contrasts in faunal communities between vegetated and bare sediments. The composition, abundance, biomass, and diversity of macrozoobenthos in both habitats were compared five times throughout the year in temperate eelgrass meadows in the southern Baltic Sea. Significant positive effects of macrophyte cover on invertebrate density and biomass were recorded only in June, July, and October when the seagrass canopy was relatively well developed. The effects of vegetation cover on faunal species richness, diversity, and composition persisted throughout the year, but the magnitude of these effects varied seasonally and followed changes in macrophyte biomass. The strongest effects were observed in July and coincided with maximums in seagrass biomass and the diversity and biomass of other macrophytes. These observations indicate that in temperate, clearly seasonal systems the assessment of macrophyte impact cannot be based solely on observations performed in just one season, especially when that season is the one in which macrophyte growth is at its maximum. The widely held belief that macrophyte cover strongly influences benthic fauna in marine coastal habitats, which is based on summer surveys, should be revisited and complemented with information obtained in other seasons.
  • Gasche, L., S. Mahévas and P. Marchal. (2013). Supporting fisheries management by means of complex models: can we point out isles of robustness in a sea of uncertainty? Plos One 8(10), e77566. doi:10.1371/journal.pone.0077566 http://dx.doi.org/10.1371%2Fjournal.pone.0077566
    View abstract Ecosystems are usually complex, nonlinear and strongly influenced by poorly known environmental variables. Among these systems, marine ecosystems have high uncertainties: marine populations in general are known to exhibit large levels of natural variability and the intensity of fishing efforts can change rapidly. These uncertainties are a source of risks that threaten the sustainability of both fish populations and fishing fleets targeting them. Appropriate management measures have to be found in order to reduce these risks and decrease sensitivity to uncertainties. Methods have been developed within decision theory that aim at allowing decision making under severe uncertainty. One of these methods is the information-gap decision theory. The info-gap method has started to permeate ecological modelling, with recent applications to conservation. However, these practical applications have so far been restricted to simple models with analytical solutions. Here we implement a deterministic approach based on decision theory in a complex model of the Eastern English Channel. Using the ISIS-Fish modelling platform, we model populations of sole and plaice in this area. We test a wide range of values for ecosystem, fleet and management parameters. From these simulations, we identify management rules controlling fish harvesting that allow reaching management goals recommended by ICES (International Council for the Exploration of the Sea) working groups while providing the highest robustness to uncertainties on ecosystem parameters.
  • Galil, B.S. (2013). Going going gone: the loss of a reef building gastropod (Mollusca: Caenogastropoda: Vermetidae) in the southeast Mediterranean Sea. Zoology in the Middle East 59(2), 179-182. doi:10.1080/09397140.2013.810885 http://dx.doi.org/10.1080/09397140.2013.810885
    View abstract The gregarous vermetid gastropods modify their environment, both ecologically and physically (Chemello & Silenzi, 2011). Yet the existence of the vermetid protected platforms which mitigate and hinder wave-induced coastal erosion depends on a delicate balance between opposing forces: vermetid accretion deposition and cementation on one hand, bioerosion and marine erosion on the other. Mediterranean vermetid reefs depend for the existence on the actively-built rims constructed by gastropods of the genus Dendropoma Morch, 1861. As early as 1961 Safriel (1966) observed that along the central coast of Israel "although the raised margins of the platforms and terraces are completely coated by Dendropoma shells, the majority of these are empty, the animals having been probably killed by overgrowth of a dense algal population". Living individual s are confined to patches clear of seaweeds, mainly found around burrows inhabited by the crab Pachygrapsus which feeds on the surrounding algae. The majority of living patches are on the exposed rims of the platforms.� With fewer individuals than are need to counterbalance marine and bio-erosion, we may fact decimation of this particular endemic seascape.
  • Galil, B.S., P. Genovesi, H. Ojaveer, G. Quílez-Badia and A. Occhipinti. (2013). Mislabeled: eco-labeling an invasive alien shellfish fishery. Biological Invasions 15(6). doi:10.1007/s10530-013-0460-9 http://dx.doi.org/10.1007/s10530-013-0460-9
    View abstract The invasive alien Manila clam fishery from Ria Arousa, Spain, was recommended for a Marine Stewardship Council certificate which implies the fishery maintains the integrity of the ecosystem. By certifying an environmentally harmful invasive alien clam fishery, the MSC harms the environment and risks its credibility, at the time when environmental responsibility and social responsibility are increasingly important to policymakers, industry, and consumers, particularly in Europe. We call on the MSC to reassess their evaluation of the Ruditapes philippinarum fishery in Ria Arousa, Spain.
  • Galil, B.S. and R. Gevili. (2013). A moveable feast: Beroe cucumis sensu Mayer, 1912 (Ctenophora; Beroida; Beroidae) preying on Mnemiopsis leidyi A. Agassiz, 1865 (Ctenophora; Lobata; Bolinopsidae) off the Mediterranean coast of Israel. BioInvasions Records 2(3), 191-194. doi:10.3391/bir.2013.2.3.03 http://dx.doi.org/10.3391/bir.2013.2.3.03
    View abstract In the winter months of 2012 and 2013 aggregations of the native comb jelly Beroe cucumis were observed and photographed along the Israeli coast preying on the invasive American comb jelly Mnemiopsis leidyi. It is suggested that native beroid may take part in controlling populations of the invasive ctenophore.
  • Hufnagl, M., M.A. Peck, R.D.M. Nash, T. Pohlmann and A.D. Rijnsdorp. (2013). Changes in potential North Sea spawning grounds of plaice (Pleuronectes platessa L.) based on early life stage connectivity to nursery habitats. Journal of Sea Research 84, 26-39. doi:http://dx.doi.org/10.1016/j.seares.2012.10.007 http://www.sciencedirect.com/science/article/pii/S1385110112001682
    View abstract We explored the hypothesis that spawning ground locations of North Sea plaice reflect the locations of nursery grounds using drift scenarios based on a baroclinic, shallow-water circulation model (HAMSOM). The transport of pelagic eggs and larvae was simulated each year from 1975 to 2006 using in situ forcing, temperature-dependent development and stage-specific behaviour of eggs and larvae. This long-term simulation period also allowed us to explore climate effects. A release position was considered a potential and suitable spawning site if larvae from that area reached coastal nurseries after the onset of metamorphosis. In general, larvae were transported in an anti-clockwise direction and settled in nurseries that were relatively close to the release positions. Spawning locations that were offshore were poorly connected to nursery grounds while those closer to the shore had higher connectivity. Simulated suitable spawning locations broadly agreed with the main centres of egg production (English Channel, Southern Bight, German Bight), except for the known spawning grounds south of Dogger Bank. Over the 31-year simulation period, positive and negative trends in transport success were found for the western and eastern parts of the North Sea, respectively. Changes in the west (Flamborough Head) were mainly due to changes in water circulation patterns whereas those in the east (northern German Bight) were induced by changes in both currents and water temperature. The implications of these findings, and the significant correlation between changes in drift and recruitment, suggest that climate-driven changes in the suitability of nursery grounds will directly affect the distribution and productivity of plaice in the North Sea.
  • Hooper, T.L. and M.C. Austen. (2013). Tidal barrages in the UK: Ecological and social impacts, potential mitigation, and tools to support barrage planning. Renewable and Sustainable Energy Reviews 23, 289-298. doi:http://dx.doi.org/10.1016/j.rser.2013.03.001 http://www.sciencedirect.com/science/article/pii/S1364032113001500
    View abstract The UK Government is committed to ambitious targets to reduce carbon emissions. The large tidal ranges in estuaries on the west coast of the UK make the deployment of tidal barrages an attractive proposition, and repeated feasibility studies have been undertaken. No barrage scheme has yet been taken forward, and one factor contributing to this reluctance to proceed is the significant environmental impacts that could result from the barrage construction and operation. This paper provides a detailed review of the current understanding of the potential ecological and social impacts of tidal barrages, including a case study of La Rance in northern France, and a discussion of strategies for mitigating barrage impacts. The review considers how more comprehensive ecological modelling could reduce uncertainty in predicting the impacts in specific estuaries, and discusses the use of Multi-criteria Analysis and ecosystem valuation as tools for evaluating the disparate costs and benefits of barrages schemes.
  • Gravili, C., C.G. Di Camillo, S. Piraino and F. Boero. (2013). Hydrozoan species richness in the Mediterranean Sea: past and present. Marine Ecology 34(Suppl. 1), 41-62. http://onlinelibrary.wiley.com/doi/10.1111/maec.12023/abstract
    View abstract The Mediterranean hydrozoan fauna (Siphonophora excluded) comprises 400 species; most (68%) occur in the Atlantic Ocean, 20% are endemic to the Mediterranean, 8% are of Indo-Pacific origin, and 4% are non-classifiable. There are 69 nonindigenous (NIS) species in the basin: 44% of these are casual (recorded just one or very few times), 28% established (widely recorded in the basin), 6% invasive (established NIS that are able rapidly or largely to disseminate away from the area of initial introduction, having a noticeable impact on the recipient community), and 22% questionable (of doubtful taxonomic status). Entry through the Suez Canal and range expansion through the Gibraltar Strait, often enhanced by ship traffic, appear to be the main processes for recent species introductions, but uncertainties remain for many NIS. Species additions immediately result in larger local or regional species pools, but the newcomers might impact on populations of native species, altering extinction probabilities. A more reliable evaluation of the species pool can be accomplished by adding new species when they enter the taxonomic record (i.e. the records of any taxon in all types of literature), and by removing species that have not been found for a "reasonable" time (e.g. several decades). Of the 400 non-siphonophoran hydrozoan species known to occur in the Mediterranean Sea, positive records in the last 10 years are available for 156 species (39%), whereas records of the remaining 244 species are older than a decade: 67 species have not been recorded for 41 years, 13 for 31-40 years, 79 for 21-30 years, and 85 for 11-20 years.
  • Galil, B.S., B. Kumar and A. Riyas. (2013). Marivagia stellata Galil and Gershwin, 2010 (Scyphozoa: Rhizostomeae: Cepheidae), found off the coast of Kerala, India. BioInvasions Records 2(4), 317-318. doi:10.3391/bir.2013.2.4.09 http://www.reabic.net/journals/bir/2013/4/BIR_2013_Galil_etal.pdf
    View abstract A specimen of the cepheid scyphozoan Marivagia stellata Galil and Gershwin, 2010, described from the Mediterranean coast of Israel, is here reported from Kerala, on the southwestern coast of India. The present record establishes M. stellata as the fourth scyphozoan species introduced to the Mediterranean through the Suez Canal.
  • Goren, M., N. Stern and B.S. Galil. (2013). Bridging the gap: first record of Mertens' prawn-goby Vanderhorstia mertensi in Israel. Marine Biodiversity Records 6, e63. doi:10.1017/s1755267213000419 http://dx.doi.org/10.1017/S1755267213000419
    View abstract The Indo-Pacific fish species Vanderhorstia mertensi was found, for the first time, off the Israeli coast in the Mediterranean. This shrimp-associated goby was reported so far only from the Mediterranean coast of Turkey. Its presence verifies the status of V. mertensi as an Erythraean alien.
  • Ferrario, J., D. Savini, A. Lodola, A. Marchini and A. Occhipinti Ambrogi. (2013). Risk of non-indigenous species introduction via international seafood trade: the case of Chioggia fish market. Biologia Marina Mediterranea 20(1), 236-237. http://www.sibm.it/Biologia%20Marina%20Mediterranea.htm
    View abstract Fish and shellfish trade and aquaculture have been increasing over the last few years due to the rising demand for live and processed products. In Italy, the most important area of production and exchange is the Adriatic Sea (www.fao.org), particularly the Lagoon of Venice. The global movement of organisms of economic interest is an important pathway of non-indigenous species (NIS) introduction into aquatic ecosystems by means of intentional release or unintentional dispersal of imported organisms-target species as well as non-target species associated with packaging (Weigle et al., 2005; Minchin, 2007). Within the EU-FP7 Project VECTORS (Vectors of Change in Ocean and Sea Marine Life, Impact on Economic Sectors) a preliminary investigation on species traded at the fish market of Chioggia, the most important fisherman locality near Venice, was carried out, with the aim of exploring the potential role of seafood trade in NIS introduction.
  • Ghabooli, S., T.A. Shiganova, E. Briski, S. Piraino, V. Fuentes, D. Thibault-Botha, D.L. Angel, M.E. Cristescu and H.J. MacIsaac. (2013). Invasion pathway of the ctenophore Mnemiopsis leidyi in the Mediterranean Sea. Plos One 8(11), e81067. doi:10.1371/journal.pone.0081067 http://dx.doi.org/10.1371%2Fjournal.pone.0081067
    View abstract Gelatinous zooplankton outbreaks have increased globally owing to a number of human-mediated factors, including food web alterations and species introductions. The invasive ctenophore Mnemiopsis leidyi entered the Black Sea in the early 1980s. The invasion was followed by the Azov, Caspian, Baltic and North Seas, and, most recently, the Mediterranean Sea. Previous studies identified two distinct invasion pathways of M. leidyi from its native range in the western Atlantic Ocean to Eurasia. However, the source of newly established populations in the Mediterranean Sea remains unclear. Here we build upon our previous study and investigate sequence variation in both mitochondrial (Cytochrome c Oxidase subunit I) and nuclear (Internal Transcribed Spacer) markers in M. leidyi, encompassing five native and 11 introduced populations, including four from the Mediterranean Sea. Extant genetic diversity in Mediterranean populations (n=8, Na=10) preclude the occurrence of a severe genetic bottleneck or founder effects in the initial colonizing population. Our mitochondrial and nuclear marker surveys revealed two possible pathways of introduction into Mediterranean Sea. In total, 17 haplotypes and 18 alleles were recovered from all surveyed populations. Haplotype and allelic diversity of Mediterranean populations were comparable to populations from which they were likely drawn. The distribution of genetic diversity and pattern of genetic differentiation suggest initial colonization of the Mediterranean from the Black-Azov Seas (pairwise FST=0.001-0.028). However, some haplotypes and alleles from the Mediterranean Sea were not detected from the well-sampled Black Sea, although they were found in Gulf of Mexico populations that were also genetically similar to those in the Mediterranean Sea (pairwise FST=0.010-0.032), raising the possibility of multiple invasion sources. Multiple introductions from a combination of Black Sea and native region sources could be facilitated by intense local and transcontinental shipping activity, respectively.
  • González-Duarte, M.M., C. Megina, S. Piraino and J.L. Cervera. (2013). Hydroid assemblages acress the Atlantic-Mediterranean boundary: is the Strait of Gibraltar a marine ecotone? Marine Ecology 34(Suppl. 1), 33-40. http://onlinelibrary.wiley.com/doi/10.1111/maec.12022/abstract
    View abstract Strong gradients in physico-chemical properties between abutting water masses create prominent transition zones in the marine environment. The Strait of Gibraltar forms the well defined boundary between the Mediterranean and Atlantic, and this paper examines spatial variation of hydroid assemblages in this transition zone. Although several studies highlighted the transitional character of the Strait and defined it as an ecotone, the benthic hydroid assemblages did not show differences between the Gulf of Cadiz and the Alboran Sea. However, there is an asymmetrical influence of the Atlantic waters on the coastal benthic ecosystems of the Alboran Sea, which maintains a more Mediterranean character in the hydroid assemblages of the northern coast, whereas a more Atlantic character was found in the rest of the studied sites. The transition zone between Atlantic and Mediterranean benthic communities could be associated with an Atlantic Influence Zone rather than with the Strait of Gibraltar itself.
  • Daewel, U., S.S. Hjøllo, M. Huret, R. Ji, M. Maar, S. Hiiranen, M. Travers-Trolet, M.A. Peck and K.E. van de Wolfshaar. (2013). Predation control of zooplankton dynamics: a review of observations and models. ICES Journal of Marine Science 71(2), 254-271. doi:10.1093/icesjms/fst125 http://dx.doi.org/10.1093/icesjms/fst125
    View abstract We performed a literature review to examine to what degree the zooplankton dynamics in different regional marine ecosystems across the Atlantic Ocean is driven by predation mortality and howthe latter is addressed in available modelling approaches. In general, we found that predation on zooplankton plays an important role in all the six considered ecosystems, but the impacts are differently strong and occur at different spatial and temporal scales. In ecosystems with extreme environmental conditions (e.g. low temperature, ice cover, large seasonal amplitudes) and low species diversity, the overall impact of top-down processes on zooplankton dynamics is stronger than for ecosystems having moderate environmental conditions and high species diversity. In those ecosystems, predation mortality was found to structure the zooplankton mainly on local spatial and seasonal time scales. Modelling methods used to parameterize zooplankton mortality range from simplified approaches with fixed mortality rates to complex coupled multispecies models. The applicability of a specific method depends on both the observed state of the ecosystem and the spatial and temporal scales considered. Modelling constraints such as parameter uncertainties and computational costs need to be balanced with the ecosystem-specific demand for a consistent, spatial-temporal dynamic implementation of predation mortality on the zooplankton compartment.
  • Coppa, S., G.A. de Lucia, P. Magni, P. Domenici, F. Antognarelli, A. Satta and A. Cucco. (2013). The effect of hydrodynamics on shell orientation and population density of Pinna nobilis in the Gulf of Oristano (Sardinia, Italy). Journal of Sea Research 76, 201-210. doi:http://dx.doi.org/10.1016/j.seares.2012.09.007 http://dx.doi.org/10.1016/j.seares.2012.09.007
    View abstract Pinna nobilis is the largest endemic bivalve of the Mediterranean Sea, declared protected since 1992. Although hydrodynamic stress induced by waves is known to influence density, size and orientation of P. nobilis, the effect of other hydrological features is unknown. This paper considers a P. nobilis population living within a Posidonia oceanica meadow in the Gulf of Oristano (Sardinia, Italy). We hypothesize that spatial differences in density and orientation of P. nobilis may be related to significant wave height (HS), wave direction (DW), bottom current direction (DBC) and bottom current speed (SBC). A population of P. nobilis was investigated at different sites and its distribution was correlated to hydrodynamics by means of a numerical modeling approach. The spatial distribution was patchy, with a density of 0.06-6.7 ind.100 m-2. A non-uniform distribution of shell orientations (OS) was demonstrated in 4 sites out of 6. DBC and SBC were the main factors affecting OS, while waves had little influence. A SBC of 0.07 m s-1 appears to be the threshold for inducing specimen directionality with shells aligned to the current and the ventral side exposed to the flow. This suggests that feeding strategy is a key factor in determining OS, in addition to drag minimization. We also highlighted the role of adjacent lagoons in supporting high densities as a result of high food availability. These findings demonstrate the usefulness of modeling techniques in explaining the spatial distribution pattern of P. nobilis and in contributing to our knowledge of its ecological traits.
  • David, M., S. Gollasch and M. Pavliha. (2013). Global ballast water management and the "same location" concept: a clear term or a clear issue? Ecological Applications 23(2), 331-338. doi:10.1890/12-0992.1 http://dx.doi.org/10.1890/12-0992.1
    View abstract The United Nations recognized the transfer of harmful organisms and pathogens across natural barriers as one of the four greatest pressures to the world's oceans and seas, causing global environmental changes, while also posing a threat to human health, property, and resources. Ballast water transferred by vessels was recognized as a prominent vector of such species and was regulated by the International Convention for the Control and Management of Ship's Ballast Water and Sediments (2004). Permanent exceptions from ballast water management requirements may apply when the uptake and discharge of ballast water occur at the "same location." However, the "same location" concept may be interpreted differently, e.g., a port basin, a port, an anchorage, or a larger area even with more ports inside. Considering that the Convention is nearing the beginning of enforcement, national authorities all around the world will soon be exposed to applications for exceptions. Here we consider possible effects of different interpretations of the "same location" concept. We have considered different possible extensions of the same location through environmental, shipping, and legal aspects. The extension of such areas, and the inclusion of more ports, may compromise the Convention's main purpose. We recommend that "same location" mean the smallest practicable unit, i.e., the same harbor, mooring, or anchorage. An entire smaller port, possibly also including the anchorage, could be considered as same location. For larger ports with a gradient of environmental conditions, "same location" should mean a terminal or a port basin. We further recommend that IMO consider the preparation of a guidance document to include concepts, criteria, and processes outlining how to identify "same location", which limits should be clearly identified.
  • David, M., S. Gollasch and E. Leppakoski. (2013). Risk assessment for exemptions from ballast water management--the Baltic Sea case study. Marine Pollution Bulletin 75(1-2), 205-217. doi:10.1016/j.marpolbul.2013.07.031 http://www.ncbi.nlm.nih.gov/pubmed/23958222
    View abstract The International Convention for the Control and Management of Ship's Ballast Water and Sediments sets requirements to prevent organism transfers. Vessels on certain routes can be exempted from such requirements based on risk assessment (RA). As the convention nears its entry into force, the interest in exemptions increases. Such RA should be conducted according to the International Maritime Organization G7 Guidelines. We present a RA study for exemptions applied to intra-Baltic shipping considering different RA methods, i.e., environmental matching, species specific method including target species and species biogeographical aspects. As reliable species data in the ports considered are unavailable and following the precautionary principle, no exemptions should be granted. To ensure data reliability, port baseline surveys and regular monitoring programs should be undertaken during the exemption period as new species found influence the RA result. The RA model prepared is considered as of value to other areas worldwide.
  • Brachvogel, R., L. Meskendahl, J.-P. Herrmann and A. Temming. (2013). Functional responses of juvenile herring and sprat in relation to different prey types. Marine Biology 160, 465-478. http://link.springer.com/article/10.1007/s00227-012-2104-5
    View abstract The relationship between particulate-feeding rates and prey concentrations (functional response) of juvenile herring and sprat (5-9 cm total length) was investigated in controlled feeding experiments monitored by an underwater camera system. A special tank system was developed allowing the regulation and quantification of low prey concentrations (1-160 L-1). Non-evasive Artemia nauplii was used as prey to estimate the maximum biting rate of both predators. In contrast, Acartia tonsa with a high escape ability was used as a realistic prey type. Herring and sprat showed a type II functional response for both prey types. Nonlinear mixed effects model revealed no significant difference between the functional responses of both predators, except that herring showed significantly higher biting rates than sprat at A. tonsa concentrations below *40 L-1. For both predators feeding rates were significantly higher with Artemia nauplii than with A. tonsa. Video analysis indicated that sprat, unlike herring, is an obligate particulate-feeder.
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