Publications by authors named "Ali S Tarkan"

Background: Biological invasions are a major threat to global biodiversity, with freshwater ecosystems being among the most susceptible to the successful establishment of non-native species and their respective potential impacts. In Poland, the introduction and spreading of non-native fish has led to biodiversity loss and ecosystem homogenisation.

Methods: Our study applies the Dispersal-Origin-Status-Impact (DOSI) assessment scheme, which is a population-level specific assessment that integrates multiple factors, including dispersal mechanisms, origin, status, and impacts, providing a nuanced framework for assessing invasion risks at local and regional levels.

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  • * A new online portal has been developed to provide up-to-date global distribution data for crayfish and their pathogens, improving accessibility and management decisions.
  • * This database is publicly available, allowing users to easily view, embed, and download data, aiming to enhance conservation planning and biodiversity management in the future.
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The contemporary management of fragmented river systems is in a trade-off between the societal benefits of instream barriers (e.g. hydropower, flood risk management) and the ecological harms of their adverse impacts on fish populations.

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In the current anthropogenic era characterised by human-induced environmental changes, long-term biomonitoring has become a crucial component for understanding ecological patterns and detecting shifts in biodiversity. However, spatiotemporal inconsistencies in biomonitoring efforts hinder transboundary progress in understanding and mitigating global environmental change effectively. The International Long-Term Ecosystem Research (ILTER) network is one of the largest standardised biomonitoring initiatives worldwide, encompassing 44 countries globally, including 26 European countries that are part of the European Long-Term Ecosystem Research network (eLTER).

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Native to Central and Eastern Europe, the euryhaline pikeperch Sander lucioperca can acclimatize to elevated salinity levels (e.g., up to 30‰), but it remains unknown whether their invasive populations use this ability to inhabit and/or disperse through brackish waters, such as estuaries and inshore areas.

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Habitat alterations and the introduction of non-native species have many ecological impacts, including the loss of biodiversity and a deterioration of ecosystem functioning. The effects of these combined stressors on the community trophic web and functional niche are, however, not completely clear. Here, we investigated how artificial ecosystems (i.

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Biological invasions pose a rapidly expanding threat to the persistence, functioning and service provisioning of ecosystems globally, and to socio-economic interests. The stages of successful invasions are driven by the same mechanism that underlies adaptive changes across species in general-via natural selection on intraspecific variation in traits that influence survival and reproductive performance (i.e.

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  • - Biological invasions are a big problem for ecosystems and economies, and Türkiye is especially at risk due to its trade connections and location between Europe and Asia.
  • - Researchers analyzed the economic costs of invasive species in Türkiye and found it added up to about $4.1 billion from 1960 to 2022, mostly affecting agriculture and fisheries.
  • - The yearly costs of these invasive species are increasing and could reach $504 million a year soon, highlighting the need for better tracking of these costs and better management strategies to deal with them.
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Non-native species can lead to severe impacts on invaded ecosystems, including the decline of ecosystem function through deleterious impacts on species diversity. The successful establishment of non-native species in new environments is the first barrier a species must overcome, ultimately depending on its ability to either cope with or adapt to local site-specific conditions. Despite the widespread distribution and ecological consequences of many freshwater invaders, site-specific and climatic preferences are often unknown.

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  • Non-native species pose a significant threat to ecosystems, creating a need for effective decision support tools to identify those likely to become invasive.
  • The Weed Risk Assessment (WRA) has inspired the creation of Invasiveness Screening Kits (ISK), with the Terrestrial Plant Species Invasiveness Screening Kit (TPS-ISK) representing the latest advancements, offering more comprehensive and effective screening capabilities.
  • The TPS-ISK provides numerous benefits over the WRA, including improved protocol standards, comprehensive questionnaires, climate change considerations, and user-friendly design, allowing for reliable risk assessments of various plant species.
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Changes in oxidative status represent organismal response to stressful external stimuli. While there is substantial knowledge on the influence of abiotic factors on the antioxidant system of different organisms, the impact of biotic factors remains largely unexplored. The aim of the present study was to evaluate the effect of acute competitive interactions on oxidative stress.

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  • - Biological invasions by species like the European perch threaten aquatic ecosystems, particularly in biodiversity-rich lakes such as İznik Lake in Turkey, impacting both the ecosystem and human well-being.
  • - Stable isotope analysis was used to predict that the introduction of perch would mainly prey on native fish species Vimba vimba and Rutilus rutilus, creating significant feeding pressure and threatening these populations.
  • - The study emphasizes the potential disruption in predator-prey relationships due to competition between the perch and the native upper predator, European catfish, urging the need for regulations and monitoring to protect native aquatic communities.
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Despite the potential ecological and economic impacts of invasive species, there is a dearth of data on the presence, impacts, and management implications of potentially invasive Orthoptera species. This lack of research and inconsistent data, including risk screenings and impact assessments, is especially evident in Europe. Consequently, assessing the status, distribution, and potential threats of nonnative Orthoptera in Europe remains challenging, impeding the development of effective management strategies.

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Biological invasions are a global challenge that has received insufficient attention. Recently available cost syntheses have provided policy- and decision makers with reliable and up-to-date information on the economic impacts of biological invasions, aiming to motivate effective management. The resultant database is now publicly and freely accessible and enables rapid extraction of monetary cost information.

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Background: Biological invasions threaten the functioning of ecosystems, biodiversity, and human well-being by degrading ecosystem services and eliciting massive economic costs. The European Union has historically been a hub for cultural development and global trade, and thus, has extensive opportunities for the introduction and spread of alien species. While reported costs of biological invasions to some member states have been recently assessed, ongoing knowledge gaps in taxonomic and spatio-temporal data suggest that these costs were considerably underestimated.

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Diplozoidae are common monogenean ectoparasites of cyprinoid fish, with the genus being the most diversified. Despite recent studies on Diplozoidae from Europe, Africa and Asia, the diversity, distribution and phylogeny of this parasite group appears to be still underestimated in the Middle East. The objective of this study was to investigate the diversity, endemism and host specificity of diplozoids parasitizing cyprinoid fish from the Middle East, considering this region as an important historical interchange of fish fauna, and to elucidate the phylogenetic position of Middle Eastern species within Diplozoidae.

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  • Monitoring oxidative stress biomarkers helps assess how organisms respond to their environment and stressors.
  • In this study, researchers examined round goby fish to see if males and females differ in their response to heat stress, hypothesizing that males would be more affected.
  • Results showed that male gobies had a stronger reaction in their liver to heat stress, suggesting that their reproductive roles make them more sensitive to environmental changes, while females prioritize their antioxidant defenses for future reproduction.
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The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium- and low-risk categories under current and predicted climate conditions.

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  • * This study utilized long-term monitoring and stable isotopes analysis to investigate the trophic behavior of the invasive channel catfish in Lake Kasumigaura, revealing significant variations in their growth and feeding habits.
  • * A new metric called the Isotopic Plasticity Index (IPI) was introduced to measure the variability in these feeding behaviors, highlighting the complex and varied impacts of invasions on native fish communities and underscoring the importance of considering trophic plasticity in management strategies.
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The western tubenose goby is one of the most wide-spread invasive fish species in European freshwaters, though information of its life-history in relation to its invasion success is limited. We compared the reproductive traits, growth rate and condition of three populations that differed in their stage of invasion in its expanding range in the River Vistula: core - the oldest population established at the centre of the invasive range; intermediate - long established by downstream dispersal from the core area but continuously supplemented by drifting specimens; front - new population at the edge of the invasive range, upstream from the core area. Pronounced differences in life-history traits were found between the 'core' and the 'front' populations.

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Rapid adaptation to global change can counter vulnerability of species to population declines and extinction. Theoretically, under such circumstances both genetic variation and phenotypic plasticity can maintain population fitness, but empirical support for this is currently limited. Here, we aim to characterize the role of environmental and genetic diversity, and their prior evolutionary history (via haplogroup profiles) in shaping patterns of life history traits during biological invasion.

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Risk screening tools are being increasingly used to identify the potential invasiveness and associated risks of non-native species. In this study, the Aquatic Species Invasiveness Screening Kit was used to evaluate the invasiveness risks of extant and horizon non-native marine fish species for the coastal waters of South Korea. In total, 57 marine fish species were screened and the threshold scores for the Basic Risk Assessment (BRA) and the BRA + Climate Change Assessment (BRA+CCA) (5.

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The aim of the present study was to risk screen 45 jellyfish species (30 hydromedusae, 14 scyphomedusae, one cubomedusa) for their potential invasiveness in the Mediterranean Sea to aid managers in making informed decisions on targeting appropriate species for management. Using the Aquatic Species Invasiveness Screening Kit (AS-ISK), calibrated basic and climate-change threshold assessment scores of 6.5 and 12.

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Facilitated by the intensification of global trading, the introduction and dispersal of species to areas in which they are historically non-native is nowadays common. From an evolutionary standpoint, invasions are paradoxical: not only non-native environments could be different from native ones for which introduced individuals would be ill-adapted, but also small founding population size should be associated with reduced adaptive potential. As such, biological invasions are considered valuable real-time evolutionary experiments.

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Non-native species are often linked to the introduction of novel pathogens with detrimental effects on native biodiversity. Since Sphaerothecum destruens was first discovered as a fish pathogen in the United Kingdom, it has been identified as a potential threat to European fish biodiversity. Despite this parasite's emergence and associated disease risk, there is still a poor understanding of its origin in Europe.

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