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Jo Ann M. Burkholder - One of the best experts on this subject based on the ideXlab platform.
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comparative impacts of two major hurricane seasons on the neuse river and western pamlico sound ecosystems
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Jo Ann M. Burkholder, Gerald S Janowitz, Martin H Posey, Greg Melia, Carol A Kinder, Cavell Brownie, David B Eggleston, Robert E. Reed, Reide D CorbettAbstract:Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle–Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive Fish Kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major Fish Kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of Fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive Fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms.
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Re-evaluation of the Relationship between Pfiesteria and Estuarine Fish Kills
Ecosystems, 2003Co-Authors: Cavell Brownie, Robert E. Reed, Jo Ann M. Burkholder, Yongqiang TangAbstract:In recent years, Fish Kills along the mid-Atlantic US coast have become an increasing problem, with important economic, environmental, and public health implications (Glasgow and others 1995; Burkholder 1998; Grattan and others 1998; Haselow and others 2001; Shoemaker and Hudnell 2001). Research into the causes of these Fish Kills is ongoing, and monitoring and surveillance programs have been instituted to investigate (among other factors) the role of actively toxic forms of two known species within the dinoflagellate genus Pfiesteria (Burkholder and others 1995, 2001a; Steidinger and others 1996; Burkholder and Glasgow 1997; Glasgow and others 2001b). In their recent analyses of the relationship between Pfiesteria and Fish Kills, Burkholder and others (1999) and Stow (1999) stated, as others have noted previously (Meyer and Barclay 1990), that it is difficult to establish the causes of estuarine Fish Kills at the ecosystem level. The evaluation of Burkholder and others (1999) was based on the biology and toxic behavior of Pfiesteria, as well as empirical sampling of field Fish kill events then in progress, as supported by laboratory analyses of samples collected from each Fish kill. In contrast, Stow (1999) conducted theoretical probability calculations and argued that information demonstrating the presence of toxic Pfiesteria during Fish Kills was insufficient to prove that there was a cause-and-effect
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Discovery of the toxic dinoflagellate Pfiesteria in northern European waters
Proceedings. Biological sciences, 2002Co-Authors: Kjetill S. Jakobsen, Parke A. Rublee, Jo Ann M. Burkholder, David W. Oldach, Howard B Glasgow, Torstein Tengs, Holly A. Bowers, Andreas Vatne, Dag KlavenessAbstract:Several dinoflagellate strains of the genus Pfiesteria were isolated by culturing techniques from sediment samples taken in the Oslofjord region of Norway. Pfiesteria piscicida, well known as a Fish killer from the Atlantic coast of America, was identified by genetic methods and light microscopy. The related species Pfiesteria shumwayae was attracted from the sediment by the presence of Fish, and has proved toxic. This present survey demonstrates the wide distribution of these potentially harmful species, but so far they have not been connected with Fish Kills in Europe.
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field ecology of toxic pfiesteria complex species and a conservative analysis of their role in estuarine Fish Kills
Environmental Health Perspectives, 2001Co-Authors: Jo Ann M. Burkholder, Michael A Mallin, Nora J Deamermelia, Robert E. ReedAbstract:Within the past decade, toxic Pfiesteria outbreaks have been documented in poorly flushed, eutrophic areas of the largest and second largest estuaries on the U.S. mainland. Here we summarize a decadal field effort in Fish kill assessment, encompassing Kills related to Pfiesteria (49 major Kills in North Carolina estuaries since 1991 and 4 in Maryland estuaries in 1997) and to other factors such as low oxygen stress (79 major Fish Kills in North Carolina estuaries). The laboratory and field data considered in developing our protocols are described, including toxic Pfiesteria behavior, environmental conditions conducive to toxic Pfiesteria activity, and impacts of toxic clonal Pfiesteria on Fish health. We outline the steps of the standardized Fish bioassay procedure that has been used since 1991 to diagnose whether actively toxic Pfiesteria was present during estuarine Fish Kills. Detailed data are given for a 1998 toxic Pfiesteria outbreak in the Neuse Estuary in North Carolina to illustrate of the full suite of diagnostic steps completed. We demonstrate that our conservative approach in implicating toxic Pfiesteria involvement in Fish Kills has biased in favor of causes other than Pfiesteria. Data are summarized from experiments that have shown stimulation of toxic Pfiesteria strains by nutrient (N, P) enrichment, supporting field observations of highest abundance of toxic strains in eutrophic estuaries. On the basis of a decade of research on toxic Pfiesteria, we present a conceptual model of the seasonal dynamics of toxic strains as affected by changing food resources and weather patterns. We also recommend protocols and research approaches that will strengthen the science of Fish kill assessment related to Pfiesteria and/or other causative factors.
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Fish Kills, bottom-water hypoxia, and the toxic Pfiesteria complex in the Neuse River and Estuary
Marine Ecology Progress Series, 1999Co-Authors: Jo Ann M. Burkholder, Michael A Mallin, Howard B GlasgowAbstract:A recent paper by Paerl et al. 'Ecosystem responses to internal and watershed organic matter loading: consequences for hypoxia in the eutrophying Neuse River Estuary, North Carolina, USA' (1998; Mar Ecol Prog Ser 166:17-25) makes the statement that increased nitrogen loading to the Neuse River Estuary has led to algal blooms which produced organic matter loads capable of causing extensive hypoxic and anoxic conditions that, in turn, have induced widespread mortality of resident finand shellFish (p l?) . In this Comment we demonstrate that Paerl et al.'s central conclusion about finFish Kills is not supported either by their data or by any statistical analysis, despite invoking predictability ('Results and discussion', p 20-24, Paerl et al. 1998). The paper contains numerous misinterpretations and misuse of literature citations. Paerl et al. also made serious errors of omission, germane from the perspective of science ethics, in failing to cite peerreviewed, published information that attributed other causality to various Fish Kills that they described. When attempting to make the difficult step from correlation to implication of causality in a field setting, the available evidence for multiple causative factors should be considered-especially when dealing with a topic that has significant implications for policy makers, scientists, and the general public. Accordingly, formal correction of the Paerl et al. paper is necessary because of the authors' (1) lack of depth profiles of dissolved oxygen (DO) data to support any of their conclusions about Kills of surface-schooling Fish, (2) use of unrecorded or nonexistent Fish kill data, as well as misconveyance of Fish Kills as reported in the State database upon which they relied, (3) apparent lack of understanding about the behavior of resident Fish population~, (4) misuse of literature citations, (5) omission of a large body of peer-reviewed, published information on the same Fish Kills (1995-1996), and (6) lack of any supporting statistical analyses to demonstrate relationships among field dissolved oxygen, nutrient, and Fish kill data. Lack of supporting dissolved oxygenlFish kill data and literature. The only DO data that Paerl et al. presented were from the bottom water. A much more complete database (laboratory of J.M.B. & H.B.G.; summary reports covering the period 1993 through 1996, available from the Division of Water Quality [DWQ] of the North Carolina Department of Environment & Natural Resources [NC DENR]) than that discussed by Paerl et al. contains information for physical, chemical, and biological factors on the mesohaline Neuse. This area (Fig. 1) includes the segments addressed in Paerl et al. and the segments where major Fish Kills historically have occurred in that estuary. Here we compare Paerl et al.'s contentions, based on biweekly data from 6 to 8 mainstem Neuse stations, with the data of our State-certified laboratory, including DO depth profiles. We report weekly data from 6 stations in the mainstem, mesohaline Neuse (Flanners Beach/Kennel Beach to MinnesottKherry Point), as well as data from freshwater segments following a major storm in late summer 1996. These data show that in summers of averageprecipitation years without hurricanes, hypoxic waters in the Neuse Estuary generally were constrained to the bottom third of the water column (Figs. 2 to 4 of this paper; hypoxia considered as in Paerl et al.). Paerl et al. stated that they used a Fish kill database from NC DWQ (formerly the Division of Environmental Management [DEM] of the NC Department of Environment, Health & Natural Resources [NC DEHNR]) as
Robert E. Reed - One of the best experts on this subject based on the ideXlab platform.
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comparative impacts of two major hurricane seasons on the neuse river and western pamlico sound ecosystems
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Jo Ann M. Burkholder, Gerald S Janowitz, Martin H Posey, Greg Melia, Carol A Kinder, Cavell Brownie, David B Eggleston, Robert E. Reed, Reide D CorbettAbstract:Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle–Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive Fish Kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major Fish Kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of Fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive Fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms.
-
Re-evaluation of the Relationship between Pfiesteria and Estuarine Fish Kills
Ecosystems, 2003Co-Authors: Cavell Brownie, Robert E. Reed, Jo Ann M. Burkholder, Yongqiang TangAbstract:In recent years, Fish Kills along the mid-Atlantic US coast have become an increasing problem, with important economic, environmental, and public health implications (Glasgow and others 1995; Burkholder 1998; Grattan and others 1998; Haselow and others 2001; Shoemaker and Hudnell 2001). Research into the causes of these Fish Kills is ongoing, and monitoring and surveillance programs have been instituted to investigate (among other factors) the role of actively toxic forms of two known species within the dinoflagellate genus Pfiesteria (Burkholder and others 1995, 2001a; Steidinger and others 1996; Burkholder and Glasgow 1997; Glasgow and others 2001b). In their recent analyses of the relationship between Pfiesteria and Fish Kills, Burkholder and others (1999) and Stow (1999) stated, as others have noted previously (Meyer and Barclay 1990), that it is difficult to establish the causes of estuarine Fish Kills at the ecosystem level. The evaluation of Burkholder and others (1999) was based on the biology and toxic behavior of Pfiesteria, as well as empirical sampling of field Fish kill events then in progress, as supported by laboratory analyses of samples collected from each Fish kill. In contrast, Stow (1999) conducted theoretical probability calculations and argued that information demonstrating the presence of toxic Pfiesteria during Fish Kills was insufficient to prove that there was a cause-and-effect
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field ecology of toxic pfiesteria complex species and a conservative analysis of their role in estuarine Fish Kills
Environmental Health Perspectives, 2001Co-Authors: Jo Ann M. Burkholder, Michael A Mallin, Nora J Deamermelia, Robert E. ReedAbstract:Within the past decade, toxic Pfiesteria outbreaks have been documented in poorly flushed, eutrophic areas of the largest and second largest estuaries on the U.S. mainland. Here we summarize a decadal field effort in Fish kill assessment, encompassing Kills related to Pfiesteria (49 major Kills in North Carolina estuaries since 1991 and 4 in Maryland estuaries in 1997) and to other factors such as low oxygen stress (79 major Fish Kills in North Carolina estuaries). The laboratory and field data considered in developing our protocols are described, including toxic Pfiesteria behavior, environmental conditions conducive to toxic Pfiesteria activity, and impacts of toxic clonal Pfiesteria on Fish health. We outline the steps of the standardized Fish bioassay procedure that has been used since 1991 to diagnose whether actively toxic Pfiesteria was present during estuarine Fish Kills. Detailed data are given for a 1998 toxic Pfiesteria outbreak in the Neuse Estuary in North Carolina to illustrate of the full suite of diagnostic steps completed. We demonstrate that our conservative approach in implicating toxic Pfiesteria involvement in Fish Kills has biased in favor of causes other than Pfiesteria. Data are summarized from experiments that have shown stimulation of toxic Pfiesteria strains by nutrient (N, P) enrichment, supporting field observations of highest abundance of toxic strains in eutrophic estuaries. On the basis of a decade of research on toxic Pfiesteria, we present a conceptual model of the seasonal dynamics of toxic strains as affected by changing food resources and weather patterns. We also recommend protocols and research approaches that will strengthen the science of Fish kill assessment related to Pfiesteria and/or other causative factors.
Howard B Glasgow - One of the best experts on this subject based on the ideXlab platform.
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Discovery of the toxic dinoflagellate Pfiesteria in northern European waters
Proceedings. Biological sciences, 2002Co-Authors: Kjetill S. Jakobsen, Parke A. Rublee, Jo Ann M. Burkholder, David W. Oldach, Howard B Glasgow, Torstein Tengs, Holly A. Bowers, Andreas Vatne, Dag KlavenessAbstract:Several dinoflagellate strains of the genus Pfiesteria were isolated by culturing techniques from sediment samples taken in the Oslofjord region of Norway. Pfiesteria piscicida, well known as a Fish killer from the Atlantic coast of America, was identified by genetic methods and light microscopy. The related species Pfiesteria shumwayae was attracted from the sediment by the presence of Fish, and has proved toxic. This present survey demonstrates the wide distribution of these potentially harmful species, but so far they have not been connected with Fish Kills in Europe.
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Fish Kills, bottom-water hypoxia, and the toxic Pfiesteria complex in the Neuse River and Estuary
Marine Ecology Progress Series, 1999Co-Authors: Jo Ann M. Burkholder, Michael A Mallin, Howard B GlasgowAbstract:A recent paper by Paerl et al. 'Ecosystem responses to internal and watershed organic matter loading: consequences for hypoxia in the eutrophying Neuse River Estuary, North Carolina, USA' (1998; Mar Ecol Prog Ser 166:17-25) makes the statement that increased nitrogen loading to the Neuse River Estuary has led to algal blooms which produced organic matter loads capable of causing extensive hypoxic and anoxic conditions that, in turn, have induced widespread mortality of resident finand shellFish (p l?) . In this Comment we demonstrate that Paerl et al.'s central conclusion about finFish Kills is not supported either by their data or by any statistical analysis, despite invoking predictability ('Results and discussion', p 20-24, Paerl et al. 1998). The paper contains numerous misinterpretations and misuse of literature citations. Paerl et al. also made serious errors of omission, germane from the perspective of science ethics, in failing to cite peerreviewed, published information that attributed other causality to various Fish Kills that they described. When attempting to make the difficult step from correlation to implication of causality in a field setting, the available evidence for multiple causative factors should be considered-especially when dealing with a topic that has significant implications for policy makers, scientists, and the general public. Accordingly, formal correction of the Paerl et al. paper is necessary because of the authors' (1) lack of depth profiles of dissolved oxygen (DO) data to support any of their conclusions about Kills of surface-schooling Fish, (2) use of unrecorded or nonexistent Fish kill data, as well as misconveyance of Fish Kills as reported in the State database upon which they relied, (3) apparent lack of understanding about the behavior of resident Fish population~, (4) misuse of literature citations, (5) omission of a large body of peer-reviewed, published information on the same Fish Kills (1995-1996), and (6) lack of any supporting statistical analyses to demonstrate relationships among field dissolved oxygen, nutrient, and Fish kill data. Lack of supporting dissolved oxygenlFish kill data and literature. The only DO data that Paerl et al. presented were from the bottom water. A much more complete database (laboratory of J.M.B. & H.B.G.; summary reports covering the period 1993 through 1996, available from the Division of Water Quality [DWQ] of the North Carolina Department of Environment & Natural Resources [NC DENR]) than that discussed by Paerl et al. contains information for physical, chemical, and biological factors on the mesohaline Neuse. This area (Fig. 1) includes the segments addressed in Paerl et al. and the segments where major Fish Kills historically have occurred in that estuary. Here we compare Paerl et al.'s contentions, based on biweekly data from 6 to 8 mainstem Neuse stations, with the data of our State-certified laboratory, including DO depth profiles. We report weekly data from 6 stations in the mainstem, mesohaline Neuse (Flanners Beach/Kennel Beach to MinnesottKherry Point), as well as data from freshwater segments following a major storm in late summer 1996. These data show that in summers of averageprecipitation years without hurricanes, hypoxic waters in the Neuse Estuary generally were constrained to the bottom third of the water column (Figs. 2 to 4 of this paper; hypoxia considered as in Paerl et al.). Paerl et al. stated that they used a Fish kill database from NC DWQ (formerly the Division of Environmental Management [DEM] of the NC Department of Environment, Health & Natural Resources [NC DEHNR]) as
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new phantom dinoflagellate is the causative agent of major estuarine Fish Kills
Nature, 1992Co-Authors: Jo Ann M. Burkholder, Edward J Noga, Cecil H Hobbs, Howard B GlasgowAbstract:A WORLDWIDE increase in toxic phytoplankton blooms over the past 20 years1,2 has coincided with increasing reports of Fish diseases and deaths of unknown cause3. Among estuaries that have been repeatedly associated with unexplained Fish Kills on the western Atlantic Coast are the Pamlico and Neuse Estuaries of the southeastern United States4. Here we describe a new toxic dinoflagellate with 'phantom-like' behaviour that has been iden-tified as the causative agent of a significant portion of the Fish Kills in these estuaries, and which may also be active in other geographic regions. The alga requires live finFish or their fresh excreta for excystment and release of a potent toxin. Low cell densities cause neurotoxic signs and Fish death, followed by rapid algal encystment and dormancy unless live Fish are added. This dinoflagellate was abundant in the water during major Fish Kills in local estuaries, but only while Fish were dying; within several hours of death where carcasses were still present, the flagellated vegetative algal population had encysted and settled back to the sediments. Isolates from each event were highly lethal to finFish and shellFish in laboratory bioassays. Given its broad temperature and salinity tolerance, and its stimulation by phosphate enrichment, this toxic phytoplankter may be a widespread but undetected source of Fish mortality in nutrient-enriched estuaries.
Timothy C. Haab - One of the best experts on this subject based on the ideXlab platform.
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The Welfare Effects of Pfiesteria-Related Fish Kills in Seafood Markets: A Contingent Behavior Analysis.” Agricultural and Resource Economic Review
2015Co-Authors: George R. Parsons, John C. Whitehead, Ash Morgan, Timothy C. HaabAbstract:We use contingent behavior analysis to study the effects of pfiesteria-related Fish Kills on the demand for seafood in the Mid-Atlantic region. We estimate a set of demand difference mod-els based on individual responses to questions about seafood consumption in the presence of Fish Kills and with different amounts of information provided about health risks. We use a ran-dom-effects Tobit model to control for correlation across each observation and to account for censoring. We find that (i) pfiesteria-related Fish Kills have a significant negative effect on the demand for seafood even though the Fish Kills pose no known threat to consumers through sea-food consumption, (ii) seafood consumers are not responsive to expert risk information de-signed to reassure them that seafood is safe in the presence of a Fish kill, and (iii) a mandatory seafood inspection program largely eliminates the welfare loss incurred due to misinformation
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The Welfare Effects of Pfiesteria-Related Fish Kills: A Contingent Behavior Analysis of Seafood Consumers
Agricultural and Resource Economics Review, 2006Co-Authors: George R. Parsons, Ash O. Morgan, John C. Whitehead, Timothy C. HaabAbstract:We use contingent behavior analysis to study the effects of pfiesteria-related Fish Kills on the demand for seafood in the Mid-Atlantic region. We estimate a set of demand difference models based on individual responses to questions about seafood consumption in the presence of Fish Kills and with different amounts of information provided about health risks. We use a random-effects Tobit model to control for correlation across each observation and to account for censoring. We find that (i) pfiesteria-related Fish Kills have a significant negative effect on the demand for seafood even though the Fish Kills pose no known threat to consumers through seafood consumption, (ii) seafood consumers are not responsive to expert risk information designed to reassure them that seafood is safe in the presence of a Fish kill, and (iii) a mandatory seafood inspection program largely eliminates the welfare loss incurred due to misinformation.
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The Welfare Effects of Pfiesteria-Related Fish Kills in Seafood Markets: A Contingent Behavior Analysis
2005Co-Authors: George R. Parsons, Ash O. Morgan, John C. Whitehead, Timothy C. HaabAbstract:We use contingent behavior analysis to study the effects of Pfiesteria related Fish Kills on the demand for seafood in the Mid-Atlantic region. We use a phone-mail-phone survey to look at the effects of various information provision mechanisms used to ameliorate the effects of misinformation regarding Fish Kills. A set of demand difference models are estimated based on individual responses to multiple questions about seafood consumption with and without Fish Kills present and with various health risk information treatments. Random effects Tobit models are used to control for the panel nature of responses and natural censoring of the stated responses. We find that 1) Pfiesteria related Fish Kills have a significant negative effect on the demand for seafood, 2) seafood consumers are nonresponsive to expert risk information designed to reassure consumers that seafood is safe in the presence of a Fish kill, and 3) a mandatory seafood inspection program completely eliminates avoidance costs incurred due to misinformation. We estimate that the aggregate avoidance costs incurred in the month immediately following a Pfiesteria related Fish kill is $50-$130 million.
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A Contingent Behavior Analysis of Seafood Consumers
2005Co-Authors: George R. Parsons, Ash O. Morgan, John C. Whitehead, Timothy C. HaabAbstract:We used contingent behavior analysis to study the effects of pfiesteria-related Fish Kills on the demand for seafood in the Mid-Atlantic region. We estimated a set demand difference models based on individual responses to questions about seafood consumption in the presence of Fish Kills and with different amounts of information provided about health risks. We used a random-effects Tobit model to control for correlation across each observation and to account for censoring. We found that 1) pfiesteria-related Fish Kills had a significant negative effect on the demand for seafood even though the Fish Kills pose no known threat to consumers through seafood consumption, 2) seafood consumers were not responsive to expert risk information designed to reassure them that seafood is safe in the presence of a Fish kill, and 3) a mandatory seafood inspection program largely eliminated the welfare loss incurred due to misinformation. Key words: pfiesteria, seafood demand, non-market valuation
Cavell Brownie - One of the best experts on this subject based on the ideXlab platform.
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comparative impacts of two major hurricane seasons on the neuse river and western pamlico sound ecosystems
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Jo Ann M. Burkholder, Gerald S Janowitz, Martin H Posey, Greg Melia, Carol A Kinder, Cavell Brownie, David B Eggleston, Robert E. Reed, Reide D CorbettAbstract:Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle–Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive Fish Kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major Fish Kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of Fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive Fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms.
-
Re-evaluation of the Relationship between Pfiesteria and Estuarine Fish Kills
Ecosystems, 2003Co-Authors: Cavell Brownie, Robert E. Reed, Jo Ann M. Burkholder, Yongqiang TangAbstract:In recent years, Fish Kills along the mid-Atlantic US coast have become an increasing problem, with important economic, environmental, and public health implications (Glasgow and others 1995; Burkholder 1998; Grattan and others 1998; Haselow and others 2001; Shoemaker and Hudnell 2001). Research into the causes of these Fish Kills is ongoing, and monitoring and surveillance programs have been instituted to investigate (among other factors) the role of actively toxic forms of two known species within the dinoflagellate genus Pfiesteria (Burkholder and others 1995, 2001a; Steidinger and others 1996; Burkholder and Glasgow 1997; Glasgow and others 2001b). In their recent analyses of the relationship between Pfiesteria and Fish Kills, Burkholder and others (1999) and Stow (1999) stated, as others have noted previously (Meyer and Barclay 1990), that it is difficult to establish the causes of estuarine Fish Kills at the ecosystem level. The evaluation of Burkholder and others (1999) was based on the biology and toxic behavior of Pfiesteria, as well as empirical sampling of field Fish kill events then in progress, as supported by laboratory analyses of samples collected from each Fish kill. In contrast, Stow (1999) conducted theoretical probability calculations and argued that information demonstrating the presence of toxic Pfiesteria during Fish Kills was insufficient to prove that there was a cause-and-effect