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Allen R Place - One of the best experts on this subject based on the ideXlab platform.
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a Fish Kill associated with a bloom of amphidinium carterae in a coastal lagoon in sydney australia
Harmful Algae, 2015Co-Authors: Shauna A. Murray, Gurjeet S Kohli, Hazel Farrell, Zoe B Spiers, Allen R Place, Juan Jose Dorantesaranda, Jason RuszczykAbstract:We report on a dense bloom (∼1.80 × 105 cells mL−1) of the marine dinoflagellate species Amphidinium carterae (Genotype 2) in a shallow, small intermittently open coastal lagoon in south eastern Australia. This bloom co-occurred with the deaths of >300 individuals of three different species of Fish. The opening of the lagoon to the ocean, as well as localized high nutrient levels, preceded the observations of very high cell numbers. A. carterae is usually benthic and sediment-dwelling, but temporarily became abundant throughout the water column in this shallow (<2 m) sandy habitat. Histopathological results showed that the Anguilla reinhardtii individuals examined had damage to epithelial and gill epithelial cells. An analysis of the bloom water indicated the presence of a compound with a retention time and UV spectra similar to Luteophanol A, a compound known from a strain of Amphidinium. Assays with a Fish gill cell line were conducted using a purified compound from cells concentrated from the bloom, and was found to cause a loss of 87% in cell viability in 6 h. The Fish deaths were likely due to the low dissolved oxygen levels in the water and/or the presence of Luteophanol A-like compounds released during the bloom.
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A Fish Kill associated with a bloom of Amphidinium carterae in a coastal lagoon in Sydney, Australia
Harmful algae, 2015Co-Authors: Shauna A. Murray, Gurjeet S Kohli, Hazel Farrell, Zoe B Spiers, Allen R Place, Juan José Dorantes-aranda, Jason RuszczykAbstract:We report on a dense bloom (∼1.80 × 105 cells mL−1) of the marine dinoflagellate species Amphidinium carterae (Genotype 2) in a shallow, small intermittently open coastal lagoon in south eastern Australia. This bloom co-occurred with the deaths of >300 individuals of three different species of Fish. The opening of the lagoon to the ocean, as well as localized high nutrient levels, preceded the observations of very high cell numbers. A. carterae is usually benthic and sediment-dwelling, but temporarily became abundant throughout the water column in this shallow (
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Ichthyotoxic Karlodinium veneficum (Ballantine) J Larsen in the Upper Swan River Estuary (Western Australia): Ecological conditions leading to a Fish Kill.
Harmful algae, 2015Co-Authors: Jason E. Adolf, Jonathan R. Deeds, Tsvetan R. Bachvaroff, Allen R PlaceAbstract:Abstract Ichthyotoxic Karlodinium veneficum has become a persistent problem in the eutrophic Swan River Estuary (SRE) near Perth, Western Australia. Karlotoxin (KmTx) concentrations and K. veneficum were sampled from March to July 2005, spanning a bloom confirmed by microscopy and genetics (ITS sequence), and a Fish Kill coincident with end of the bloom. The objective of this study was to investigate K. veneficum cell and toxin dynamics, and water quality conditions, leading up to the bloom and Fish Kill in this estuarine system. Abundance of K. veneficum increased as diatom abundance decreased over a 3-month period (Jan–Mar) preceding the bloom. Low freshwater flow to the SRE characterized the bloom initiation period, while elevated seasonal flows altered water quality and preceded the end of the bloom and Fish Kill. The bloom of K. veneficum was localized over a bottom layer of hypoxic water in a stratified water column. Low nitrate levels, DIN:DIP (mol) near unity, and particulate C:N:P of K. veneficum-rich water samples were consistent with nitrogen limitation of phytoplankton. A KmTx 2 congener was present in the concentration range 0–1052 ng KmTx mL−1, levels that were sufficient to Kill larval Fish in the laboratory within 4 h. A KmTx cell quota of 2.8 pg KmTx cell−1 was estimated for the bloom, which is moderately high for the species. Gill histopathology of Fish from this Fish Kill showed signs of damage similar to those caused by KmTx in the lab. Results from this study suggest that conditions in the SRE, including elevated K. veneficum abundance and KmTx cell quotas, as well as hypoxia in the upper SRE, likely contribute to seasonal Fish Kills observed in this system.
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Dinoflagellate community analysis of a Fish Kill using denaturing gradient gel electrophoresis
Harmful Algae, 2005Co-Authors: Qian Wang, Allen R Place, Jonathan R. Deeds, Robert BelasAbstract:A molecular method using the polymerase chain reaction (PCR) amplification of small subunit gene sequences (18S rDNA) and denaturing gradient gel electrophoresis (DGGE) was used to determine both the population complexity and species identification of organisms in harmful algal blooms. Eighteen laboratory cultures of dinoflagellates, including Akashiwo, Gymnodinium, Heterocapsa, Karenia, Karlodinium, Pfiesteria, and Pfiesteria-like species were analyzed using dinoflagellate-specific oligonucleotide primers and DGGE. The method is sensitive and able to determine the number of species in a sample, as well as the taxonomic identity of each species, and is particularly useful in detecting differences between species of the same genus, as well as differences between morphologically similar species. Using this method, each of eight Pfiesteria-like species was verified as being clonal isolates of Pfiesteria piscicida. The sensitivity of dinoflagellate DGGE is approximately 1000 cells/ml, which is 100-fold less sensitive than real-time PCR. However, the advantage of DGGE lies in its ability to analyze dinoflagellate community structure without needing to know what is there, while real-time PCR provides much higher sensitivity and detection levels, if probes exist for the species of interest, attributes that complement DGGE analysis. In a blinded test, dinoflagellate DGGE was used to analyze two environmental Fish Kill samples whose species composition had been previously determined by other analyses. DGGE correctly identified the dominant species in these samples as Karlodinium micrum and Heterocapsa rotundata, proving the efficacy of this method on environmental samples. Toxin analysis of a clonal isolate obtained from the Fish Kill samples confirmed the presence of KmTx2, corroborating the earlier genetic identification of toxic K. micrum in the Fish Kill water sample.
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toxicity of karlodinium micrum dinophyceae associated with a Fish Kill in a south carolina brackish retention pond
Harmful Algae, 2002Co-Authors: Jason W Kempton, Jonathan R. Deeds, Alan J Lewitus, Mchugh J Law, Allen R PlaceAbstract:Abstract A dinoflagellate bloom was found associated with a Fish Kill event in a South Carolina brackish water retention pond. A multi-analytical approach was used to confirm the identity of the bloom dinoflagellate and evaluate its potential toxicity. Karlodinium micrum was confirmed through light microscopy, pigment profile comparisons, species-specific PCR, and gene sequence data. Necropsy findings on several Fish were suggestive of an acute Kill event. Toxicity of filtrate from bloom samples was tested by a hemolytic assay using rainbow trout ( Oncorhynchus mykis ) erythrocytes and an ichthyotoxicity assay using larval zebraFish ( Danio rerio ). Hemolytic activity was measurably high (>80% hemolysis) in both whole filtrate and fractionated filtrate (from the 80% MeOH C 18 column elution). This fraction also demonstrated high ichthyotoxic activity as exposed Fish experienced rapid death. These results implicate toxic K. micrum as a causative factor in Fish death in a non-aquaculture brackish pond associated with a housing development, and extend recent findings linking this species to Fish Kills in aquaculture ponds.
Tim J. Wrigley - One of the best experts on this subject based on the ideXlab platform.
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factors contributing to a Fish Kill in the australian wet dry tropics
Water Research, 1992Co-Authors: Simon A. Townsend, Kevin T. Boland, Tim J. WrigleyAbstract:Abstract Factors which contributed to the death of 5000 Fish, comprising 18 species, and accompanying water quality changes in Donkey Camp Pool, a part of the Katherine River system in the Australian wet/dry tropics, are discussed. The water quality of the pool was modified by the first run-off of the 1987–1988 wet season. A similar run-off event 9 days later caused significant water quality changes. Colour, turbidity, iron and manganese were at least an order of magnitude greater and coliform concentrations several orders of magnitude higher than typical dry season values. Furthermore, the pool was stratified with low surface dissolved oxygen concentrations and anoxic conditions at depth. These conditions remained until the pool was completely flushed by a large run-off event 11 days later. The Fish Kill was primarily related to natural causes associated with low dissolved oxygen concentrations. The pool water was displaced with cool run-off from a tributary of the Katherine River which carried a substantial organic load and had a high oxygen demand. It is concluded that the low dissolved oxygen concentrations were the major cause of the Fish Kill with possible additional harmful effects from toxic humic compounds. The event highlights the significant impact storm run-off can have on the quality of receiving waters in the Australian wet/dry tropics.
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Factors contributing to a Fish Kill in the Australian wet/dry tropics
Water Research, 1992Co-Authors: Simon A. Townsend, Kevin T. Boland, Tim J. WrigleyAbstract:Abstract Factors which contributed to the death of 5000 Fish, comprising 18 species, and accompanying water quality changes in Donkey Camp Pool, a part of the Katherine River system in the Australian wet/dry tropics, are discussed. The water quality of the pool was modified by the first run-off of the 1987–1988 wet season. A similar run-off event 9 days later caused significant water quality changes. Colour, turbidity, iron and manganese were at least an order of magnitude greater and coliform concentrations several orders of magnitude higher than typical dry season values. Furthermore, the pool was stratified with low surface dissolved oxygen concentrations and anoxic conditions at depth. These conditions remained until the pool was completely flushed by a large run-off event 11 days later. The Fish Kill was primarily related to natural causes associated with low dissolved oxygen concentrations. The pool water was displaced with cool run-off from a tributary of the Katherine River which carried a substantial organic load and had a high oxygen demand. It is concluded that the low dissolved oxygen concentrations were the major cause of the Fish Kill with possible additional harmful effects from toxic humic compounds. The event highlights the significant impact storm run-off can have on the quality of receiving waters in the Australian wet/dry tropics.
Sheikh Raisuddin - One of the best experts on this subject based on the ideXlab platform.
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biomarkers of oxidative stress in wallago attu bl and sch during and after a Fish Kill episode at panipat india
Science of The Total Environment, 2006Co-Authors: Suhel Parvez, Suwarna Pandey, Mehboob Ali, Sheikh RaisuddinAbstract:The present investigation was carried out by sampling water, sediment and Fish during a Fish-Kill episode at Panipat (Haryana, India), and again sampling at the same site was conducted after a gap of two months. During the second sampling no Fish-Kill was observed and the water was relatively less turbid and clear. Antioxidant profile and lipid peroxidation (LPO) in Fish tissues were studied. Analysis was also carried out on the physico-chemical characteristics of water samples along with heavy metal and pesticide analysis in water and sediment samples during and after the episode. Dissolved oxygen level was substantially low during the Fish-Kill episode. Heavy metals (copper and chromium) and pesticides like BHC (Benzene hexachloride), DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) were also detected during the episode in water and sediment samples. Various oxidative stress biomarkers in liver, kidney and gill tissues in the Indian freshwater Fish Wallago attu (Bl. and Sch.) collected from the site were investigated. The levels of reduced glutathione and non-protein thiol were significantly (P < 0.001) higher in the liver of Wallago attu collected from Panipat after the Fish-Kill episode. Ascorbic acid levels in all the tissues did not change significantly after the episode. The LPO in liver, kidney and gills was significantly low (P < 0.01–0.001) in all tissues of Fish collected after the Fish-Kill episode. The protein carbonyl levels were significantly low (P < 0.05–0.01) in all the Fish organs sampled after the Fish-Kill episode. The findings suggest that industrial effluent may result in the massive loss of a commercial commodity. The simultaneous measurement of the physicochemical parameters of the water samples showed a good correlation between the biomarkers responses and the environmental chemical stress conditions.
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Biomarkers of oxidative stress in Wallago attu (Bl. and Sch.) during and after a Fish-Kill episode at Panipat, India.
The Science of the total environment, 2006Co-Authors: Suhel Parvez, Suwarna Pandey, Mehboob Ali, Sheikh RaisuddinAbstract:The present investigation was carried out by sampling water, sediment and Fish during a Fish-Kill episode at Panipat (Haryana, India), and again sampling at the same site was conducted after a gap of two months. During the second sampling no Fish-Kill was observed and the water was relatively less turbid and clear. Antioxidant profile and lipid peroxidation (LPO) in Fish tissues were studied. Analysis was also carried out on the physico-chemical characteristics of water samples along with heavy metal and pesticide analysis in water and sediment samples during and after the episode. Dissolved oxygen level was substantially low during the Fish-Kill episode. Heavy metals (copper and chromium) and pesticides like BHC (Benzene hexachloride), DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) were also detected during the episode in water and sediment samples. Various oxidative stress biomarkers in liver, kidney and gill tissues in the Indian freshwater Fish Wallago attu (Bl. and Sch.) collected from the site were investigated. The levels of reduced glutathione and non-protein thiol were significantly (P
Simon A. Townsend - One of the best experts on this subject based on the ideXlab platform.
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factors contributing to a Fish Kill in the australian wet dry tropics
Water Research, 1992Co-Authors: Simon A. Townsend, Kevin T. Boland, Tim J. WrigleyAbstract:Abstract Factors which contributed to the death of 5000 Fish, comprising 18 species, and accompanying water quality changes in Donkey Camp Pool, a part of the Katherine River system in the Australian wet/dry tropics, are discussed. The water quality of the pool was modified by the first run-off of the 1987–1988 wet season. A similar run-off event 9 days later caused significant water quality changes. Colour, turbidity, iron and manganese were at least an order of magnitude greater and coliform concentrations several orders of magnitude higher than typical dry season values. Furthermore, the pool was stratified with low surface dissolved oxygen concentrations and anoxic conditions at depth. These conditions remained until the pool was completely flushed by a large run-off event 11 days later. The Fish Kill was primarily related to natural causes associated with low dissolved oxygen concentrations. The pool water was displaced with cool run-off from a tributary of the Katherine River which carried a substantial organic load and had a high oxygen demand. It is concluded that the low dissolved oxygen concentrations were the major cause of the Fish Kill with possible additional harmful effects from toxic humic compounds. The event highlights the significant impact storm run-off can have on the quality of receiving waters in the Australian wet/dry tropics.
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Factors contributing to a Fish Kill in the Australian wet/dry tropics
Water Research, 1992Co-Authors: Simon A. Townsend, Kevin T. Boland, Tim J. WrigleyAbstract:Abstract Factors which contributed to the death of 5000 Fish, comprising 18 species, and accompanying water quality changes in Donkey Camp Pool, a part of the Katherine River system in the Australian wet/dry tropics, are discussed. The water quality of the pool was modified by the first run-off of the 1987–1988 wet season. A similar run-off event 9 days later caused significant water quality changes. Colour, turbidity, iron and manganese were at least an order of magnitude greater and coliform concentrations several orders of magnitude higher than typical dry season values. Furthermore, the pool was stratified with low surface dissolved oxygen concentrations and anoxic conditions at depth. These conditions remained until the pool was completely flushed by a large run-off event 11 days later. The Fish Kill was primarily related to natural causes associated with low dissolved oxygen concentrations. The pool water was displaced with cool run-off from a tributary of the Katherine River which carried a substantial organic load and had a high oxygen demand. It is concluded that the low dissolved oxygen concentrations were the major cause of the Fish Kill with possible additional harmful effects from toxic humic compounds. The event highlights the significant impact storm run-off can have on the quality of receiving waters in the Australian wet/dry tropics.
Alan J Lewitus - One of the best experts on this subject based on the ideXlab platform.
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a novel heterosigma akashiwo raphidophyceae bloom extending from a south carolina bay to offshore waters
Harmful Algae, 2008Co-Authors: Jason W Kempton, Alan J Lewitus, Charles J Keppler, Andrew Shuler, Susan B WildeAbstract:Abstract In April 2003, a novel Heterosigma akashiwo bloom was observed that extended from Bulls Bay, South Carolina USA, to approximately 8 km offshore. The bloom was associated with a Fish Kill of approximately 104 Fish. The bloom coincided with salinities anomalously low for the region and optimal for H. akashiwo growth. The low salinities were related to the rediversion of freshwater a month earlier from the Cooper River into the Santee River, which partially feeds into Bulls Bay. H. akashiwo identification was confirmed using a species-specific real-time PCR assay modified for the direct amplification of target DNA from the bloom sample. Because this H. akashiwo bloom was associated with a Fish Kill, and exposure to bloom waters caused sublethal toxic effects on oysters, the resolution of the cause and potential recurrence of the bloom are of importance to Fishery management.
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toxicity of karlodinium micrum dinophyceae associated with a Fish Kill in a south carolina brackish retention pond
Harmful Algae, 2002Co-Authors: Jason W Kempton, Jonathan R. Deeds, Alan J Lewitus, Mchugh J Law, Allen R PlaceAbstract:Abstract A dinoflagellate bloom was found associated with a Fish Kill event in a South Carolina brackish water retention pond. A multi-analytical approach was used to confirm the identity of the bloom dinoflagellate and evaluate its potential toxicity. Karlodinium micrum was confirmed through light microscopy, pigment profile comparisons, species-specific PCR, and gene sequence data. Necropsy findings on several Fish were suggestive of an acute Kill event. Toxicity of filtrate from bloom samples was tested by a hemolytic assay using rainbow trout ( Oncorhynchus mykis ) erythrocytes and an ichthyotoxicity assay using larval zebraFish ( Danio rerio ). Hemolytic activity was measurably high (>80% hemolysis) in both whole filtrate and fractionated filtrate (from the 80% MeOH C 18 column elution). This fraction also demonstrated high ichthyotoxic activity as exposed Fish experienced rapid death. These results implicate toxic K. micrum as a causative factor in Fish death in a non-aquaculture brackish pond associated with a housing development, and extend recent findings linking this species to Fish Kills in aquaculture ponds.