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Ralf Reinartz - One of the best experts on this subject based on the ideXlab platform.
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first evidence of hybridization between endangered sterlets acipenser ruthenus and exotic siberian Sturgeons acipenser baerii in the danube river
Biological Invasions, 2009Co-Authors: Arne Ludwig, Sebastian Lippold, Lutz Debus, Ralf ReinartzAbstract:Most natural populations of Eurasian Sturgeons have declined dramatically during recent decades, reaching historic low levels today. During the same period, Sturgeon has become very popular in European aquaculture. Because many hatcheries are located near rivers, their unintentional escape is often documented, especially during floods. Until now, no cases of successful hybridization of these escaped fish with wild stocks have been reported. In this study, the genetic structure of a highly threatened population of sterlets (Acipenser ruthenus) from the Upper Danube was analysed as a requirement for their conservation. Surprisingly, we observed genotypes and morphotypes of Siberian Sturgeon (Acipenser baerii), as well as hybrids between this species and native sterlets. This hybridization poses a serious threat for the survival of this isolated sterlet population in the upper part of the Danube. For the first time, natural reproduction is documented for Siberian Sturgeon outside their natural range in Europe. This finding demonstrates the risk of extinction by hybridisation of endangered populations. We would like to stress that taking into consideration the risks for native Sturgeon populations, farmed Sturgeon should not be released into the wild, and all measures should be taken to prevent their accidental escape.
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an action plan for the conservation of Sturgeons acipenseridae in the danube river basin
Österreichische Wasser- und Abfallwirtschaft, 2006Co-Authors: Jürg Bloesch, Ralf Reinartz, T. Jones, B StriebelAbstract:Six species of Sturgeons are native to the Danube River Basin, five are classified as either ‘Endangered’ or ‘Critically Endangered’, and one ‘Vulnerable’ according to the 2004IUCN Red List of Threatened Species. In fact, one of the five endangered species, the Atlantic Sturgeon (Acipenser sturio), is already extinct in the Danube River Basin. The key threats to Danube Sturgeons include: Over-exploitation (over-fishing linked with poaching and illegal trade), habitat loss and degradation including the disruption of spawning migrations and pollution, and potential alteration of the genetic and ecological status by the introduction of exotic species and genotypes. In December 2005, a Sturgeon Action Plan, jointly prepared by experts and stakeholders, was adopted by the Standing Committee of the Bern Convention in the frame of the Council of Europe. It puts forward a series of Objectives and associated Actions required to achieve the Plan’s ultimate Goal formulated as follows: “Through national action and international cooperation, to secure viable populations of all Danube Sturgeon species and forms by sustainable management and by restoration of their natural habitats and migratory movements”.
Arne Ludwig - One of the best experts on this subject based on the ideXlab platform.
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first evidence of hybridization between endangered sterlets acipenser ruthenus and exotic siberian Sturgeons acipenser baerii in the danube river
Biological Invasions, 2009Co-Authors: Arne Ludwig, Sebastian Lippold, Lutz Debus, Ralf ReinartzAbstract:Most natural populations of Eurasian Sturgeons have declined dramatically during recent decades, reaching historic low levels today. During the same period, Sturgeon has become very popular in European aquaculture. Because many hatcheries are located near rivers, their unintentional escape is often documented, especially during floods. Until now, no cases of successful hybridization of these escaped fish with wild stocks have been reported. In this study, the genetic structure of a highly threatened population of sterlets (Acipenser ruthenus) from the Upper Danube was analysed as a requirement for their conservation. Surprisingly, we observed genotypes and morphotypes of Siberian Sturgeon (Acipenser baerii), as well as hybrids between this species and native sterlets. This hybridization poses a serious threat for the survival of this isolated sterlet population in the upper part of the Danube. For the first time, natural reproduction is documented for Siberian Sturgeon outside their natural range in Europe. This finding demonstrates the risk of extinction by hybridisation of endangered populations. We would like to stress that taking into consideration the risks for native Sturgeon populations, farmed Sturgeon should not be released into the wild, and all measures should be taken to prevent their accidental escape.
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the enigmatic caspian sea russian Sturgeon how many cryptic forms does it contain
Systematics and Biodiversity, 2005Co-Authors: Vadim J Birstein, Phaedra Doukakis, Arne Ludwig, Georgii Ruban, Rob DesalleAbstract:Abstract The Russian Sturgeon, Acipenser gueldenstaedtii, is closely related to three other Sturgeon species (A persicus, A. naccarii and A baerii), with populations in the Caspian Sea containing a cryptic lineage with an A. baerii‐like mtDNA profile. Using morphological evidence (morphometrics, meristics) and additional genetic analysis (cytochrome b gene and control region sequencing), cryptic lineages within the Russian Sturgeon and their relation to other closely related species of Sturgeons are further examined. These data indicate that three genetic forms exist within what is presently known as A. gueldenstaedtii. These forms include the pure A. gueldenstaedtii and A. baerii‐like individuals plus a third rare genetic form whose mtDNA is similar to the mtDNA of the Adriatic Sturgeon, A. naccarii. Morphological comparison of the three forms and the Yenisei River A baerii indicates that although the three forms of A. gueldenstaedtii are not different from one another, all three significantly differ fro...
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a fixed allele at microsatellite locus ls 39 exhibiting species specificity for the black caviar producer acipenser stellatus
Journal of Applied Ichthyology, 2001Co-Authors: Ingo Jenneckens, Lutz Debus, Bernie May, J N Meyer, Gabriele Horstgenschwark, H Wedekind, Arne LudwigAbstract:Summary The Sturgeon microsatellite LS-39 was amplified across 10 diAerent species of Acipenserinae and exhibited the potential to identify the black caviar producer Acipenser stellatus on a genomic DNA level. This was because of a fixed allele of 111 bp, which was absent in the other species which were investigated. Concerning the source of Sturgeon species, LS-39 is the first nuclear marker described to examine black caviar. Furthermore, new light is shed on the controversial ploidy state of Sturgeons. The present authors findings at this microsatellite locus support the hypothesis that extant 120 chromosomal species are modern diploids, whereas Sturgeons with 240 chromosomes should be considered as modern tetraploids.
Rob Desalle - One of the best experts on this subject based on the ideXlab platform.
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the enigmatic caspian sea russian Sturgeon how many cryptic forms does it contain
Systematics and Biodiversity, 2005Co-Authors: Vadim J Birstein, Phaedra Doukakis, Arne Ludwig, Georgii Ruban, Rob DesalleAbstract:Abstract The Russian Sturgeon, Acipenser gueldenstaedtii, is closely related to three other Sturgeon species (A persicus, A. naccarii and A baerii), with populations in the Caspian Sea containing a cryptic lineage with an A. baerii‐like mtDNA profile. Using morphological evidence (morphometrics, meristics) and additional genetic analysis (cytochrome b gene and control region sequencing), cryptic lineages within the Russian Sturgeon and their relation to other closely related species of Sturgeons are further examined. These data indicate that three genetic forms exist within what is presently known as A. gueldenstaedtii. These forms include the pure A. gueldenstaedtii and A. baerii‐like individuals plus a third rare genetic form whose mtDNA is similar to the mtDNA of the Adriatic Sturgeon, A. naccarii. Morphological comparison of the three forms and the Yenisei River A baerii indicates that although the three forms of A. gueldenstaedtii are not different from one another, all three significantly differ fro...
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molecular identification of acipenser sturio specimens a warning note for recovery plans
Biological Conservation, 1998Co-Authors: Vadim J Birstein, Jessica Betts, Rob DesalleAbstract:Partial sequences of the cytochrome b gene were generated for six Sturgeons caught recently in the historic range of Acipenser sturio. Four samples studied were identified as A. sturio: two individuals from the Gironde River (France), and two individuals caught in the North and Baltic Seas. Two remaining samples were identified as from the clade of fishes which includes the Adriatic Sturgeon A. naccarii and Siberian Sturgeon A. baerii. Several DNA sequence differences were found between individuals of A. sturio from the Gironde River population and from the North and Baltic Seas. A careful genetic evaluation of each captured putative A. sturio individual which potentially can be used for breeding in restoration projects is recommended.
Vadim J Birstein - One of the best experts on this subject based on the ideXlab platform.
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the enigmatic caspian sea russian Sturgeon how many cryptic forms does it contain
Systematics and Biodiversity, 2005Co-Authors: Vadim J Birstein, Phaedra Doukakis, Arne Ludwig, Georgii Ruban, Rob DesalleAbstract:Abstract The Russian Sturgeon, Acipenser gueldenstaedtii, is closely related to three other Sturgeon species (A persicus, A. naccarii and A baerii), with populations in the Caspian Sea containing a cryptic lineage with an A. baerii‐like mtDNA profile. Using morphological evidence (morphometrics, meristics) and additional genetic analysis (cytochrome b gene and control region sequencing), cryptic lineages within the Russian Sturgeon and their relation to other closely related species of Sturgeons are further examined. These data indicate that three genetic forms exist within what is presently known as A. gueldenstaedtii. These forms include the pure A. gueldenstaedtii and A. baerii‐like individuals plus a third rare genetic form whose mtDNA is similar to the mtDNA of the Adriatic Sturgeon, A. naccarii. Morphological comparison of the three forms and the Yenisei River A baerii indicates that although the three forms of A. gueldenstaedtii are not different from one another, all three significantly differ fro...
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molecular identification of acipenser sturio specimens a warning note for recovery plans
Biological Conservation, 1998Co-Authors: Vadim J Birstein, Jessica Betts, Rob DesalleAbstract:Partial sequences of the cytochrome b gene were generated for six Sturgeons caught recently in the historic range of Acipenser sturio. Four samples studied were identified as A. sturio: two individuals from the Gironde River (France), and two individuals caught in the North and Baltic Seas. Two remaining samples were identified as from the clade of fishes which includes the Adriatic Sturgeon A. naccarii and Siberian Sturgeon A. baerii. Several DNA sequence differences were found between individuals of A. sturio from the Gironde River population and from the North and Baltic Seas. A careful genetic evaluation of each captured putative A. sturio individual which potentially can be used for breeding in restoration projects is recommended.
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Sturgeon biodiversity and conservation
Copeia, 1997Co-Authors: Vadim J Birstein, John R Waldman, William E BemisAbstract:Prelude to Sturgeon Biodiversity and Conservation E.K. Balon. Sturgeon Biodiversity and Conservation: An Introduction W.E. Bemis, et al. Part 1: Diversity and Evolution of Sturgeons and Paddlefishes. An Overview of Acipenseriformes W.E. Bemis, et al. Osteology and Phylogenetic Interrelationships of Sturgeons (Acipenseridae) E.K. Findeis. Phylogeny of the Acipenseriformes: Cytogenetic and Molecular Approaches V.J. Birstein, et al. How Many Species are there within the Genus Acipenser? V.J. Birstein, W.E. Bemis. Part 2: Biology and Status Reports on Sturgeons and Paddlefishes. Sturgeon Rivers: An Introduction to Acipenseriform Biogeography and Life History W.E. Bemis, B. Kynard. Past and Current Status of Sturgeons in the Upper and Middle Danube River K. Hensel, J. Holcik. Endangered Migratory Sturgeons of the Lower Danube River and its Delta N. Bacalbasa-Dobrovici. Present Status of Commercial Stocks of Sturgeons in the Caspian Sea Basin R.P. Khodorevskaya, et al. Species Structure, Contemporary Distribution and Status of the Siberian Sturgeon, Acipenser baerii G.I. Ruban. Endemic Sturgeons of the Amur River: Kaluga, Huso dauricus, and Amur Sturgeon, Acipenser schrenckii M.L. Krykhtin, V.G. Svirskii. Biology, Fisheries, and Conservation of Sturgeons and Paddlefish in China Q. Wei, et al. Biology and Life History of Dabry's Sturgeon, Acipenser dabryanus, in the Yangtze River P. Zhuang, et al. Observations on the Reproductive Cycle of Cultured White Sturgeon, Acipenser transmontanus S.I. Doroshov, et al. Contemporary Status of the North American Paddlefish, Polyodon Spathula K. Graham. Life History and Status of the Shovelnose Sturgeon, Scaphirhynchusplatorynchus K.D. Keenlyne. The Status and Distribution of Lake Sturgeon, Acipenser fulvescens, in the Canadian Provinces of Manitoba, Ontario and Quebec: a Genetic Perspective M.M. Ferguson, G.A. Duckworth. Lake Sturgeon Management in the Menominee River, a Wisconsin-Michigan Boundary Water T.F. Thuemler. Life History, Latitudinal Patterns, and Status of the Shortnose Sturgeon, Acipenser brevirostrum B. Kynard. Status and Management of Atlantic Sturgeon, Acipenser oxyrinchus, in North America T.I.J. Smith, J.P. Clugston. Atlantic and Shortnose Sturgeons of the Hudson River: Common and Divergent Life History Attributes M.B. Bain. Biological Characteristics of the European Atlantic Sturgeon, Acipenser sturio, as the Basis for a Restoration Program in France P. Williot, et al. Part 3: Controversies, Conservation and Summary. Sturgeons in the Aral Sea Ecological Catastrophe I. Zholdasova. Threatened Fishes of the World: Pseudoscaphirhynchus spp. (Acipenseridae) V.J. Birstein. Molecular Analysis in the Conservation of Sturgeons and Paddlefish I.I. Wirgin, et al. Sensitivity of North American Sturgeons and Paddlefish to Fishing Mortality J. Boreman. Alternatives for the Protection and Restoration of Sturgeons and their Habitat R.C.P. Beamesderfer, R.A. Farr. Threatened Fishes of the World: Scaphirhynchus suttkusi Williams & Clemmer, 1991 R.L. Mayden, B.R. Kuhajda. Threatened Fishes of the World: Scaphirhynchus albus (Forbes & Richardson, 1905) R.L. Mayden, B.R. Kuhajda. Sturgeon Poaching and Black Market Caviar: A Case Study A. Cohen. The Threatened Status of Acipenseriform Fishes: A Summary B.J. Birstein, et al. Species and Subject Index.
Markus Hecker - One of the best experts on this subject based on the ideXlab platform.
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Background Results
2016Co-Authors: Jon Doering, Steve Wiseman, John P Giesy, Markus Hecker, Shawn Beitel, Figure Juvenile, White SturgeonAbstract:• Worldwide many species of Sturgeons (Acipenseridae) have faced massive population declines with some species nearing extinction. • These declines are attributed to a variety of human activities including habitat alteration, overfishing, and pollution. • Sturgeon are uniquely susceptible to bioaccumulation of dioxin-like compounds relative to other species of fish because they: are extremely long lived have a higher lipid content mature later • Deformities and enzyme induction have been observed in Sturgeon collected from some contaminated sites however, little is known about the sensitivity of Sturgeon to dioxin-like compounds. • White Sturgeon have been found to be highly responsive to exposure to a model dioxin-like compound (β-naphthoflavone) with regard to inducibility of cytochrome P450 1A (Demonstrated in Figure 1 from Doering et al, 2012)
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Acknowledgements
2016Co-Authors: Jon Doering, Steve Wiseman, John P Giesy, Shawn Beitel, Sarah Patterson, Song Tang, Bryanna Eisner, Markus HeckerAbstract:• Worldwide many species of Sturgeons (Acipenseridae) have faced massive population declines with some species nearing extinction. • These declines are attributed to a variety of human activities including pollution. • Due to their benthic nature and longevity, Sturgeons are at risk to bioaccumulative contaminants, such as dioxin-like compounds. • The pleiotropic responses of exposure to dioxin-like compounds are mediated through activation of the aryl hydrocarbon receptor (AhR) signaling pathway. • AhR1 and AhR2 of white Sturgeon have been shown to be the most sensitive AhRs studied to date to exposure to 2,3,7,8-TCDD in vitro using transfected COS-7 cells (Table 1). • However, nothing is known about the transcriptional responses of AhR activation in Sturgeons or the resulting toxic responses
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functionality of aryl hydrocarbon receptors ahr1 and ahr2 of white Sturgeon acipenser transmontanus and implications for the risk assessment of dioxin like compounds
Environmental Science & Technology, 2014Co-Authors: Jon A Doering, Reza Farmahin, Steve Wiseman, Sean W Kennedy, John P Giesy, Markus HeckerAbstract:Worldwide, populations of Sturgeons are endangered, and it is hypothesized that anthropogenic chemicals, including dioxin-like compounds (DLCs), might be contributing to the observed declines in populations. DLCs elicit their toxic action through activation of the aryl hydrocarbon receptor (AhR), which is believed to regulate most, if not all, adverse effects associated with exposure to these chemicals. Currently, risk assessment of DLCs in fishes uses toxic equivalency factors (TEFs) developed for the World Health Organization (WHO) that are based on studies of embryo-lethality with salmonids. However, there is a lack of knowledge of the sensitivity of Sturgeons to DLCs, and it is uncertain whether TEFs developed by the WHO are protective of these fishes. Sturgeons are evolutionarily distinct from salmonids, and the AhRs of Sturgeons differ from those of salmonids. Therefore, this study investigated the sensitivity of white Sturgeon (Acipenser transmontanus) to DLCs in vitro via the use of luciferase rep...
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Functionality of Aryl Hydrocarbon Receptors (AhR1 and AhR2) of White Sturgeon (Acipenser transmontanus) and Implications for the Risk Assessment of Dioxin-like Compounds
2014Co-Authors: Jon A Doering, Reza Farmahin, Steve Wiseman, Sean W Kennedy, John P Giesy, Markus HeckerAbstract:Worldwide, populations of Sturgeons are endangered, and it is hypothesized that anthropogenic chemicals, including dioxin-like compounds (DLCs), might be contributing to the observed declines in populations. DLCs elicit their toxic action through activation of the aryl hydrocarbon receptor (AhR), which is believed to regulate most, if not all, adverse effects associated with exposure to these chemicals. Currently, risk assessment of DLCs in fishes uses toxic equivalency factors (TEFs) developed for the World Health Organization (WHO) that are based on studies of embryo-lethality with salmonids. However, there is a lack of knowledge of the sensitivity of Sturgeons to DLCs, and it is uncertain whether TEFs developed by the WHO are protective of these fishes. Sturgeons are evolutionarily distinct from salmonids, and the AhRs of Sturgeons differ from those of salmonids. Therefore, this study investigated the sensitivity of white Sturgeon (Acipenser transmontanus) to DLCs in vitro via the use of luciferase reporter gene assays using COS-7 cells transfected with AhR1 or AhR2 of white Sturgeon. Specifically, activation and relative potencies (RePs) of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachloro-dibenzofuran, 2,3,7,8-tetrachloro-dibenzofuran, 3,3′,4,4′,5-pentachlorobiphenyl, 3,3′,4,4′-tetrachlorobiphenyl, and 2,3,3′,4,4′-pentachlorobiphenyl were determined for each AhR. It was demonstrated that white Sturgeon expresses AhR1s and AhR2s that are both activated by DLCs with EC50 values for 2,3,7,8-TCDD that are lower than those of any other AhR of vertebrates tested to date. Both AhRs of white Sturgeon had RePs for polychlorinated dibenzofurans more similar to TEFs for birds, while RePs for polychlorinated biphenyls were most similar to TEFs for fishes. Measured concentrations of select DLCs in tissues of white Sturgeon from British Columbia, Canada, were used to calculate toxic equivalents (TEQs) by use of TEFs for fishes used by the WHO and TCDD equivalents (TCDD-EQs) via the use of RePs for AhR2 of white Sturgeon as determined by transfected COS-7 cells. TCDD-EQs calculated for endangered populations of white Sturgeon were approximately 10-fold greater than TEQs and were within ranges known to cause adverse effects in other fishes, including other species of Sturgeons. Therefore, TEFs used by the WHO might not adequately protect white Sturgeon, illuminating the need for additional investigation into the sensitivity of these fish to DLCs
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Functionality of aryl hydrocarbon receptors (AhR1 and AhR2) of white Sturgeon (Acipenser transmontanus) and implications for the risk assessment of dioxin-like compounds
2014Co-Authors: Jon A Doering, Reza Farmahin, Steve Wiseman, Sean W Kennedy, Markus Hecker, ‡,⊥,#,∇,○ John P Giesy, Environment CanadaAbstract:ABSTRACT: Worldwide, populations of Sturgeons are endangered, and it is hypothesized that anthropogenic chemicals, including dioxin-like compounds (DLCs), might be contributing to the observed declines in populations. DLCs elicit their toxic action through activation of the aryl hydrocarbon receptor (AhR), which is believed to regulate most, if not all, adverse effects associated with exposure to these chemicals. Currently, risk assessment of DLCs in fishes uses toxic equivalency factors (TEFs) developed for the World Health Organization (WHO) that are based on studies of embryo-lethality with salmonids. However, there is a lack of knowledge of the sensitivity of Sturgeons to DLCs, and it is uncertain whether TEFs developed by the WHO are protective of these fishes. Sturgeons are evolutionarily distinct from salmonids, and the AhRs of Sturgeons differ from those of salmonids. Therefore, this study investigated the sensitivity of white Sturgeon (Acipenser transmontanus) to DLCs in vitro via the use of luciferase reporter gene assays using COS-7 cells transfected with AhR1 or AhR2 of white Sturgeon. Specifically, activation and relative potencies (RePs) of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran, 2,3,7,8-tetrachloro-dibenzofuran, 3,3′,4,4′,5-pentachlorobiphenyl, 3,3′,4,4′-tetrachlorobiphenyl, and 2,3,3′,4,4′-pentachlorobiphenyl were determined for each AhR. It was demonstrated that white Sturgeon expresses AhR1s and AhR2s that are both activated by DLCs with EC 50 values for 2,3,7,8-TCDD that are lower than those of any other AhR of vertebrates tested to date. Both AhRs of white Sturgeon had RePs for polychlorinated dibenzofurans more similar to TEFs for birds, while RePs for polychlorinated biphenyls were most similar to TEFs for fishes. Measured concentrations of select DLCs in tissues of white Sturgeon from British Columbia, Canada, were used to calculate toxic equivalents (TEQs) by use of TEFs for fishes used by the WHO and TCDD equivalents (TCDD-EQs) via the use of RePs for AhR2 of white Sturgeon as determined by transfected COS-7 cells. TCDD-EQs calculated for endangered populations of white Sturgeon were approximately 10-fold greater than TEQs and were within ranges known to cause adverse effects in other fishes, including other species of Sturgeons. Therefore, TEFs used by the WHO might not adequately protect white Sturgeon, illuminating the need for additional investigation into the sensitivity of these fish to DLCs
