5,629 research outputs found

    A review of mechanically stimulated bioluminescence of marine plankton and its applications

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    Bioluminescence is ubiquitous in marine ecosystems and found in uni- and multicellular organisms. Bioluminescent displays can be used to deter predators, attract mates, and lure and hunt prey. Mechanically stimulated flash kinetics of zooplankton and dinoflagellates are life stage-dependent and species-specific, and could prove effective at identification and monitoring biodiversity in bioluminescent species. Here, we provide a comprehensive review of mechanically stimulated bioluminescence for the main dinoflagellate and zooplankton clades in marine environments and assemble known flash kinetics and spectral emission data. Instruments and methods used in measuring bioluminescence are also discussed. Applications, research gaps, perspectives, and biases in approaches to studying bioluminescence are identified. Moreover, emission kinetics of most zooplankton are very poorly known and constitute a critical gap. Lastly, available knowledge is interpreted in terms of potential future changes in global bioluminescence driven by climate change

    Spatial analysis of demersal food webs through integration of eDNA metabarcoding with fishing activities

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    The evaluation of the status of marine communities, and especially the monitoring of those heavily exploited by fisheries, is a key, challenging task in marine sciences. Fishing activities are a major source of disruption to marine food webs, both directly, by selectively removing components at specific trophic levels (TL), and indirectly, by altering habitats and production cycles. Food web analysis can be very useful in the context of an Ecosystem Approach to Fisheries, but food web reconstructions demand large and expensive data sets, which are typically available only for a small fraction of marine ecosystems. Recently, new technologies have been developed to easily, quickly and cost-effectively collect environmental DNA (eDNA) during fishing activities. By generating large, multi-marker metabarcoding data from eDNA samples obtained from commercial trawlers, it is possible to produce exhaustive taxonomic inventories for the exploited ecosystems, which are suitable for food-web reconstructions. Here, we integrate and re-analyse the data of a recent study in which the α diversity was investigated using the eDNA opportunistically collected during fishing operations. Indeed, we collect highly resolved information on species feeding relationships to reconstruct the food webs at different sites in the Strait of Sicily (Mediterranean Sea) from eDNA and catch data. After observing that the trophic networks obtained from eDNA metabarcoding data are more consistent with the available knowledge, a set of food web indicators (species richness, number of links, direct connectance and generality) is computed and analysed to unravel differences in food webs structure through different areas (spatial variations). Species richness, number of links and generality (positively) and direct connectance (negatively) are correlated with increasing distance from the coast and fishing effort intensity. The combined effects of environmental gradients and fishing effort on food web structure at different study sites are then examined and modelled. Taken together, these findings indicate the suitability of eDNA metabarcoding to assist and food web analysis, obtain several food web-related ecological indicators, and tease out the effect of fishing intensity from the environmental gradients of marine ecosystems

    Microplastic burden in marine benthic invertebrates depends on species traits and feeding ecology within biogeographical provinces

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    This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: The research data supporting this publication are openly available from Harvard Dataverse at: https://doi.org/10.7910/DVN/E57LOA. The data for the Van Sebille 2015 model can be found at: https://figshare.com/collections/data_of_Van_Sebille_et_al_2015_ERL_paper/5764184. Ocean boundaries (Spalding’s Provinces) used in Fig. 1 are freely available at: https://www.worldwildlife.org/publications/marine-ecoregions-of-the-world-a-bioregionalization-of-coastal-and-shelf-areas. Longhurst provinces used as a geographical variable in the initial analysis are freely available from: https://www.marineregions.org/gazetteer.php?p=details&id=22538. The world country shapefiles used in Fig. 1 are available from ESRI at: https://hub.arcgis.com/datasets/esri::world-countries-generalized/about and available for use under the ESRI Master License Agreement. Taxonomy for all species was verified and curated using the World Register of Marine Species match taxa function available at: https://www.marinespecies.org/aphia.php?p=match. Biological trait categories were modified using those provided by the Marine Life Information Network (MarLIN) Biological Traits Information Catalogue (BIOTIC) available at: https://www.marlin.ac.uk/biotic/resources.php. Latitudes and Longitudes when not specifically mentioned in the individual study were approximated using Google Maps.The microplastic body burden of marine animals is often assumed to reflect levels of environmental contamination, yet variations in feeding ecology and regional trait expression could also affect a species' risk of contaminant uptake. Here, we explore the global inventory of individual microplastic body burden for invertebrate species inhabiting marine sediments across 16 biogeographic provinces. We show that individual microplastic body burden in benthic invertebrates cannot be fully explained by absolute levels of microplastic contamination in the environment, because interspecific differences in behaviour and feeding ecology strongly determine microplastic uptake. Our analyses also indicate a degree of species-specific particle selectivity; likely associated with feeding biology. Highest microplastic burden occurs in the Yellow and Mediterranean Seas and, contrary to expectation, amongst omnivores, predators, and deposit feeders rather than suspension feeding species. Our findings highlight the inadequacy of microplastic uptake risk assessments based on inventories of environmental contamination alone, and the need to understand how species behaviour and trait expression covary with microplastic contamination.Natural Environment Research Council (NERC

    Helminths found in common species of the herpetofauna in Ukraine

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    Only a few comprehensive studies have been carried out on parasites in amphibians and reptiles in Ukraine. This has resulted in identifying over 100 helminth species across these vertebrate groups. However, most of the studies were performed in the 20th century and the taxonomy of many parasites and their hosts has changed ever since, in addition to the discovery of new species and registrations of species that had not been previously known for Ukraine. In recent decades, there have been very few publications on helminths from amphibian or reptile hosts in this region. Notably, just one of these recent studies is a faunistic study, providing a list of helminths found in two species of green frogs – Pelophylax ridibundus (Pallas, 1771) and Pelophylax esculentus (Linnaeus, 1758). Therefore, it is clear that publishing datasets of modern records of helminths in these vertebrate groups, based on modern taxonomy, is an essential step in further studies of their parasitic diversity. Additionally, such study is important in terms of global climate change, the growing number of possibilities of invasion of alien species (both hosts and parasites) that might potentially become a threat to native biota and growing anthropogenic pressure on local populations of hosts that affect the parasites as well. In future, this study is planned to be used for the creation of a checklist of helminths of the herpetofauna of Ukraine. The present dataset is an inventory of various species of helminths parasitising common species of the herpetofauna in central, northern, western and southern Ukraine recorded during field studies in the 2021-2023 period.The dataset is the first one to represent the up-to-date and unified data on helminths of reptiles and amphibians of Ukraine. Previously, records of this group of organisms with reference to their hosts were presented as several separate records within the country. Currently, this is the largest dataset presenting geocoded records of non-human-related helminths in the fauna of Ukraine. It reports helminth species from 15 hosts (205 individuals), including eight amphibians and seven reptilian species found in various Ukrainian regions. A total of 47 helminth species have been documented in the research and during 2021-2023 period on the territory of northern (Kyiv and Zhytomyr), western (Lviv, Zakarpattia Ivano-Frankivsk), central (Vinnytsia, Dnipropetrovsk, Cherkasy, Zaporizhzhia and Poltava) and southern (Odesa) regions of Ukraine. The identified helminth species belong to the following phyla: Acanthocephala (Centrorhynchidae (2), Echinorhynchidae (2)); Nematoda (Acuariidae, Anisakidae, Cosmocercidae (3), Dioctophymatidae, Gnathostomatidae (1), Kathlanidae (1), Molineidae (7), Onchocercidae (1), Pharyngodonidae (1), Rhabdiasidae (6), Strongyloididae); Platyhelminthes (Diplodiscidae (1), Diplostomidae (2), Encyclometridae (1), Haematoloechidae (1), Leptophallidae (2), Macroderidae (1), Mesocestoididae, Opisthorchiidae (2), Plagiorchiidae (3), Pleurogenidae (2), Polystomatidae (3), Proteocephalidae (1), Strigeidae (1) and Telorchiidae (3)). Only some helminths in the dataset were not identified to species level. Material is stored in the collection of the department of Parasitology of the I. I. Schmalhausen Institute of Zoology NAS of Ukraine

    Status of urban ecology in Africa: a systematic review

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    Urbanization is an extreme human activity and is expanding worldwide, consequently increasing the attention of scientists across research areas of urban ecology. Recent studies have warned of the lack of information from certain regions, particularly Africa, which is rapidly urbanizing. Thus, we did a detailed literature search to determine the state of knowledge in African urban ecology in the last century. We found 795 relevant papers from where data were collected and tested to understand geographic and ecological mismatches in research effort, allowing us to identify important knowledge gaps (e.g., taxonomy and scientific fields). We also tested the effect of current and future urbanization intensity, human population density, size and conservation status of ecoregions and Gross Domestic Product (GDP) on research effort. Our results suggest a low turnout of papers and a dearth of knowledge about African urban ecology. Studies were conducted in 72% of African countries, with South Africa alone accounting for almost 40% of all published papers. The studies were either conducted at the city (55%) or local/country (34%) level, suggesting the lack of transnational research collaboration. Interestingly, only country GDP and the size and conservation status of ecoregions significantly predicted the number of publications, suggesting that research effort is driven by economic reasons and the relevance of conservation in African urban ecology. We need to account for these biases to advance our understanding of the impacts of urbanization on African biodiversity

    ECOfast – An integrative ecological evaluation index for an ecosystem-based assessment of shallow rocky reefs

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    The degradation of marine ecosystems is a growing concern worldwide, emphasizing the need for efficient tools to assess their ecological status. Herein, a novel ecosystem-based ecological evaluation index of shallow rocky reefs is introduced and tested in the Aegean and Ionian Seas (NE Mediterranean). The index focuses on a specific set of pre-selected species, including habitat-forming, key, commercially important, and non-indigenous species, across a wide range of trophic levels (1.00–4.53). Data acquisition is conducted through rapid non-destructive SCUBA diving surveys to assess all macroscopic food web components (macroalgae, invertebrates, and fish). Two versions of the index, ECOfast and ECOfast-NIS, were developed, each applying a different approach to account for the impact of non-indigenous species. In our case study, the correlations between the two versions of the index and sea surface temperature, protection status, occurrence of carnivorous fish, and non-indigenous herbivores were assessed through generalized additive models (GAMs). The assessment assigned 93% (ECOfast) or 96% (ECOfast-NIS) of the sites to a moderate to bad ecological status, indicating an alarming situation in the shallow rocky reefs of the NE Mediterranean. Sites evaluated as poor or bad were characterized by extensive coverage of ephemeral macroalgae, absence or minimal presence of large indigenous carnivorous fish, and complete absence of one to three out of five invertebrate functional trophic groups. The community composition of macroalgae, herbivorous species, and carnivorous fishes differed between the 5 m and 15 m depth zones. Surface temperature and carnivorous fish occurrence were the most important tested predictors of the ecological status of shallow rocky reefs. The best GAMs showed that the ECOfast score declined with sea surface temperature and increased with the occurrence of carnivorous fish; ECOfast-NIS declined with sea surface temperature and the occurrence of non-indigenous fish and increased with the occurrence of carnivorous fish. The non-destructive and integrative nature of this approach, its speed of data acquisition and analysis, and its capacity to account for highly mobile predatory fish and non-indigenous species render the ECOfast index a novel, robust, and valuable tool for assessing the ecological status of shallow rocky reefs

    Population Growth Model and Mortality of Pakistan Lobster (Panulirus polyphagus) in Estuary Waters of Tarakan City

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    Lobster Panulirus polyphagus has a fairly high economic value and is found in the estuary waters of Tarakan City. This research aims to study the growth and mortality model of Lobster P. polyphagus originating in the estuary waters of Tarakan City. The research method was carried out using a quantitative descriptive method. Sampling was conducted 14 times from December 2021-May 2022 using gill nets. The results showed that the male sex ratio was more than the female. Allometric growth of males and females is negative allometric with a thin body shape. The structure of the size obtained was mostly in males ranging from 18.3-20.6 cm, and females around 20.5-22.2 cm. The maximum length growth of P. polyphagus based on von Bertalanffy's growth model was 31.519 cm in males and 31.374 cm in females. The total mortality (Z) of P. polyphagus for males and females was 1.104 and 1.119; catch mortality (F) of 0.106 and 0.253; natural mortality (M) of 0.998 and 0.866; exploitation rate (E) of 0.096 and 0.226, respectively. The high natural mortality causes the extinction of the Lobster species, so good management is needed so that it is sustainable

    First record of peregrine shrimp Metapenaeus stebbingi Nobili, 1904 (Crustacea, Decapoda: Penaeidae) in the Iraqi waters, North-West Arabian Gulf

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    One male specimen of the species Metapenaeus stebbingi Nobili, 1904 was first recorded in November 2021 from the Iraqi territorial waters, Northwest of the Arabian Gulf. Therefore, the investigated shrimp species nominally corresponds to the original description of M. stebbing through the main diagnostic features. It must be adopted in the spread and expansion of species, a new record of the area, and a distinctive addition to the species of commercial shrimp within the Iraqi marine waters

    Fish aggregating devices (FADs) as conservation tools: understanding community dynamics at pelagic moored FADs

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    The pelagic ocean covers the majority of the planet and is the largest ecosystem by volume. It is estimated to harbor considerable biodiversity, and a few select species support some of the largest fisheries in existence. The expanse of the open ocean provides important resources and services to humans, and also poses challenges to understanding the biology and ecology of its resident species. Focusing effort, both fishing and research, on hotspots or other aggregation sites increases the feasibility of interacting with these often patchily-distributed animals. Fish aggregating devices (FADs) have become a widespread fishing tool in many of the world’s oceans. Leveraging the natural behavior of many fish species to aggregate around floating or submerged structures, FADs are used to increase the capture efficiency in a range of marine fisheries and the scale of their use has raised concerns around potential effects these artificial structures have on the ecosystems in which they are used. Research efforts have focused on understanding these impacts by taking advantage of the fisheries-related opportunities and data made available by these fishing tools and the fleets that use them. However, this may potentially bias studies towards fishing hotspots and larger, commercially important species. Here, we discuss how subsurface FADs, purpose-built and discretely deployed, can act as useful research platforms to address important pelagic ecology questions and conservation topics. We describe the colonization of new FADs and the aggregation fluctuations through long-term video and visual surveys, provide evidence for invertebrate micronekton aggregation as a potential mechanism behind fish attraction to FADs, and detail a new acoustic telemetry array design that can provide previously unavailable position metrics of tagged fish in the open ocean, a notably challenging habitat to study. These new data and scientific tools will allow for the continued and enhanced study of the pelagic ecosystem and the diversity of species that inhabit it

    Monitoring Arthropods in maize and pasture fields in São Miguel and São Jorge Islands: IPM-Popillia Project

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    ABSTRACT: The dataset presented here is an achievement of the H2020 European project "Integrated Pest Management of the Invasive Japanese Beetle, Popillia japonica (IPM-Popillia)". This project addresses the challenge of a new risk to plant health in Europe, the invasion of the Japanese beetle, Popillia japonica (Newman, 1838) (Coleoptera, Rutelidae) and provides an environmentally friendly IPM Toolbox to control the expanding pest populations across Europe. This study aims to present the records of terrestrial arthropod diversity with a special focus on four groups belonging to Carabids and Staphylinid beetles (Coleoptera), Opiliones and Anisolabididae (Dermaptera), collected with the potential to be used as biocontrol agents against P. japonica in future Integrated Pest Management programmes. A thorough sampling programme was conducted in maize and pasture fields in two Islands of the Azores (São Miguel and São Jorge) in the summer of 2022.info:eu-repo/semantics/publishedVersio
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