Concern over the potential transfer of aquatic nuisance species (ANS) between the Great Lakes bas... more Concern over the potential transfer of aquatic nuisance species (ANS) between the Great Lakes basin and the Upper Mississippi River basin has motivated calls to re-establish hydrologic separation between the two basins. Accomplishing that goal would require significant expenditures to re-engineer waterways in the Chicago, IL area. These costs should be compared to the potential costs resulting from ANS transfer between the basin, a significant portion of which would be costs to recreational fisheries. In this study, a recreational behavior model is developed for sport anglers in an eight-state region. It models how angler behavior would change in response to potential changes in fishing quality resulting from ANS transfer. The model also calculates the potential loss in net economic value that anglers enjoy from the fishery. The model is estimated based on data on trips taken by anglers (travel cost data) and on angler statements about how they would respond to changes in fishing qu...
Background Shallow nearshore marine ecosystems are changing at an increasing rate due to a range ... more Background Shallow nearshore marine ecosystems are changing at an increasing rate due to a range of human activities such as urbanisation and commercial development. As a result, an increasing number of structural modifications occur in coastal nursery and spawning habitats of fish. Concomitant to this increase, there have been declines in many coastal fish populations and changes in the composition of fish communities. As requested by Swedish stakeholders, this review aimed to synthesise scientific evidence of the impact on fish recruitment of structural modifications in temperate coastal areas. Methods We searched for peer-reviewed and grey literature on such impacts in English, Dutch, Danish, Finnish, German, Swedish and Spanish. Searches were performed in bibliographic databases, specialist websites, bibliographies of review articles. We also contacted stakeholder to find relevant literature. Eligible studies included small- and large-scale field studies in marine systems and la...
DNA barcode data hosted in the Data Portal of the Barcode of Life Data Systems. Records consist o... more DNA barcode data hosted in the Data Portal of the Barcode of Life Data Systems. Records consist of specimen metadata, specimen images, and sequence data.
Day 1 of the workshop was devoted to several lectures and shorter presentations by the participan... more Day 1 of the workshop was devoted to several lectures and shorter presentations by the participants. The lectures included three presentations on theory and techniques and four case studies (Great Lakes, Rivers, Lakes, Marine): Guy Fleischer, USGS-BRD, Ann Arbor, MI: Target strength of Great Lakes fishes John Horne: NOAA Great Lakes Laboratory, Ann Arbor, MI: Theoretical scattering models for predicting target strength and the choice of operating frequency: applications to alewife and smelt in the Great Lakes Patrick Sullivan, Cornell University, Ithaca NY: Survey design, introduction to the theory Doran Mason, Purdue University. Acoustics in Lake Superior. Kyle Hartman, West Virgnia University: Acoustics in riversthe Hudson experience Paul Walline, Lake Kinneret Laboratory, Israel: Acoustics in lakes the Lake Kinneret experience Fredrik Arrhenius, Marine Laboratory, Sweden. Acoustics in oceans -Atlantic herring in the Norwegian Sea.
Canadian Journal of Fisheries and Aquatic Sciences, 2016
Walleye (Sander vitreus), smallmouth bass (Micropterus dolomieu), and largemouth bass (Micropteru... more Walleye (Sander vitreus), smallmouth bass (Micropterus dolomieu), and largemouth bass (Micropterus salmoides) are common top predators across many north temperate lakes, but no previous analyses have assessed factors driving their combined impact on mortality of a shared prey, yellow perch (Perca flavescens). We estimated consumption dynamics of walleye, smallmouth bass, and largemouth bass during 3 years that differed in age-0 yellow perch year-class strength and evaluated the relative contribution of each predator to age-0 yellow perch mortality, in Oneida Lake, New York, USA. Habitat-specific diet composition and population densities were integrated with temperature and growth rates to parameterize a bioenergetics model and estimate annual consumption of major diet items. Walleye were the dominant predator in both offshore and inshore habitats, while smallmouth bass and largemouth bass were also important inshore predators. Consumption of age-0 yellow perch by all three predators...
Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem pro... more Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis) have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and increases in water clarity resulting in increases in benthic algae. We found that the presence of zebra mussels alone (ZM), quagga mussels alone (QM), or an equal number of both species (ZQ) reduced total phosphorus (TP) and phytoplankton Chl a. Total suspended solids (TSS) was reduced in ZM and ZQ treatments. Light intensity at the sediment surface was higher in all three mussel treatments than in the no-mussel controls but there was no difference among the mussel treatments. There was no incr...
Journal of agricultural and food chemistry, Jan 19, 2016
The fatty acid profiles of wild freshwater fish are poorly characterized as a human food source f... more The fatty acid profiles of wild freshwater fish are poorly characterized as a human food source for several classes of fatty acids, particularly for branched chain fatty acids (BCFA), a major bioactive dietary component known to enter the U.S. food supply primarily via dairy and beef fat. We evaluated the fatty acid content of 27 freshwater fish species captured in the northeastern U.S. with emphasis on the BCFA and bioactive polyunsaturated fatty acids (PUFA) most associated with fish, specifically n-3 (omega 3) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Mean BCFA content across all species were 1.0±0.5% (mean ± SD) of total fatty acids in edible muscle, with rainbow smelt (O. mordax) and pumpkinseed (L. gibbosus) the highest at >2% BCFA. In comparison, EPA+DHA constituted 28%±7% of total fatty acids. Across all fish species, the major BCFA were iso-15:0, anteiso-15:0, iso-16:0, iso-17:0 and anteiso-17:0. Fish skin had significantly higher BCFA content than musc...
Abstract The conference ‘Ecology of Fish in Lakes and Reservoirs’ (ECOFIL 2014) was held in Septe... more Abstract The conference ‘Ecology of Fish in Lakes and Reservoirs’ (ECOFIL 2014) was held in September 2014 in Ceske Budĕjovice, Czech Republic. More than 110 lectures and posters presented during the meeting documented rapid methodological developments in freshwater fisheries science and recent advances of studies of biotic integrity and quality of fish stocks required by the EU Water framework Directive and the US and Canadian Fisheries Agencies. Most contributions focused on the main conference themes of the role of fish in trophic webs, spatiotemporal patterns, effects of environmental and anthropogenic stressors, fisheries management and ecological status.
Oneida Lake, New York, is the State’s second most heavily fished body of water, receiving some 30... more Oneida Lake, New York, is the State’s second most heavily fished body of water, receiving some 300,000 angler-hours of effort annually. Walleye account for 60-80% of the targeted effort on the lake and harvest rates typically run over 90% of the legal-sized catch. With support of the New York State Department of Environmental Conservation, the Cornell Biological Field Station has monitored walleye population dynamics for 55 years. Through the 1980s, the adult walleye population fluctuated between 500,000 and 900,000 fish, and was tightly linked to yellow perch dynamics. Both angler catch rates and survival of young walleye were linked to abundance of young yellow perch, serving to stabilize the predator-prey dynamics of the lake. Beginning in the 1980s, a series of perturbations disrupted the dynamics of the system. In the late 1980s, white perch and gizzard shad, previously present at low levels, began to increase in abundance. In the early 1990s, zebra mussels colonized the lake a...
Background/Question/Methods Intra-annual survival of larval and age-0 rainbow smelt (Osmerus mord... more Background/Question/Methods Intra-annual survival of larval and age-0 rainbow smelt (Osmerus mordax) in Lake Champlain was studied in relation to adult abundance and gradients in the physical aquatic environment. Spatial dynamics of rainbow smelt are key to rainbow smelt population dynamics because this species is cannibalistic and the rate of cannibalism is a function of spatial overlap and fish density. Thus, our objective was to determine how physical environmental gradients are related to rainbow smelt distribution then determine subsequent cannibalism rates and mortality of young fish. Using day and night hydroacoustic data from 2007 and 2008, we created generalized additive mixed effects models to predict rainbow smelt vertical distribution as a function of temperature and light. We compared predicted and observed cannibalism and subsequent mortality of age-0 fish as a function of fish distribution. Results/Conclusions We found highest intra-annual mortality occurred during sp...
To better understand, and subsequently reduce, uncertainty in pelagic fish population data, analy... more To better understand, and subsequently reduce, uncertainty in pelagic fish population data, analyses were conducted on simultaneously-collected trawl and hydroacoustic data from over 200 sampling events in Lake Champlain, a mesotrophic freshwater lake located between New York (USA), Vermont (USA), and Quebec (Canada). A model set, which used a number of factors to explore sources of variance, was analyzed. Factors explored were acoustic density estimation method, sampling time, sampling season, water temperature, light, invertebrate presence, fish size, fish species, and collection depth. Trawl avoidance was higher during the day, and varied with trawl type. Sources of variance in hydroacoustic estimates were the size and depth of analysis regions, presence of invertebrates, and fish shoaling behavior. All fish species could not be differentiated using acoustic target strength, thus necessitating trawl collections to estimate species-specific abundance. Trawl collection showed verti...
Recent declines in epilimnetic nutrients and zooplankton biomass have resulted in a shift towards... more Recent declines in epilimnetic nutrients and zooplankton biomass have resulted in a shift towards deeper production in Lake Ontario. As a result, there has been an increase in the deep chlorophyll layer (DCL) during the stratified period. In turn, zooplankton grazing and subsequent nutrient regeneration may occur at deeper depths, possibly affecting the production of planktivorous fishes and invertebrates. Given Lake Ontario’s reliance on Alewife to sustain salmonid fisheries, understanding tropic shifts in food webs is of particular importance. In this study we used a diel approach to describe trophic interactions of planktivores and their prey within and around Lake Ontario’s DCL during 2013. During spring mysids appear to graze heavily on diatoms, but in July and September mysids switch to zooplanktivory and compete with Alewife and Rainbow Smelt for prey. The predatory impact of the invasive spiny water flea Bythotrephes was minimal in Lake Ontario during 2013. Bythotrephes abun...
Zooplankton biomass has decreased an order of magnitude in the offshore epilimnion of Lake Ontari... more Zooplankton biomass has decreased an order of magnitude in the offshore epilimnion of Lake Ontario during the last decade, with the largest decreases in smaller zooplankton (Bosmina and Diacyclops). These decreases cannot be attributed to alewife planktivory, because alewife has declined during this time period. However, the invasive predatory cladoceran Bythotrephes has increased since 2005 which may be a result of decreased alewife planktivory. Other invertebrate predators include the cladocerans Cercopagis, Leptodora and Polyphemus, several copepods (e.g. Limnocalanus), and the mysid Mysis diluviana (relicta). We analyze the time trends in zooplanktivory from these invertebrates from 2000 to 2010 using bioenergetics models. Zooplanktivory by invertebrates increased due to the increase in Bythotrephes although Mysis continues to be important. The role of omnivores like Limnocalanus is increasing. Understanding recent changes in zooplankton abundance and community composition in La...
ABSTRACT Mysid shrimp are important both as predators on zooplankton and as prey for a variety of... more ABSTRACT Mysid shrimp are important both as predators on zooplankton and as prey for a variety of fish species across most of the Laurentian Great Lakes. In Lake Champlain, where little is known about mysids, this may also be true. We evaluated the role of Mysis diluviana as a planktivore in Lake Champlain using hydroacoustics, gut content analysis, stable isotopes, cohort analysis, and bioenergetics models to estimate Mysis density, diets, growth rates, and prey consumption rates. Density of Mysis in the water column of the deeper Main Lake was lower in July–August of 2008–2011 (38, 38, 21, and 74 Mysis/m2, respectively) than historical values from the 1970s. Mysis selectively foraged for cladocerans, but also consumed cyclopoid and calanoid copepods in 2011. Stable isotope data suggest a mostly carnivorous diet, although agreement between isotope mixing models and observed diets varied. Cohort analyses revealed growth rates ranging from 2.7 mm/month in late spring to 1.3 mm/month in late summer. In contrast to the offshore areas of Lake Ontario and Lake Huron, zooplankton consumption by the Mysis population was low relative to zooplankton density and production indicating that Mysis are not currently a major zooplanktivore in Lake Champlain.
Concern over the potential transfer of aquatic nuisance species (ANS) between the Great Lakes bas... more Concern over the potential transfer of aquatic nuisance species (ANS) between the Great Lakes basin and the Upper Mississippi River basin has motivated calls to re-establish hydrologic separation between the two basins. Accomplishing that goal would require significant expenditures to re-engineer waterways in the Chicago, IL area. These costs should be compared to the potential costs resulting from ANS transfer between the basin, a significant portion of which would be costs to recreational fisheries. In this study, a recreational behavior model is developed for sport anglers in an eight-state region. It models how angler behavior would change in response to potential changes in fishing quality resulting from ANS transfer. The model also calculates the potential loss in net economic value that anglers enjoy from the fishery. The model is estimated based on data on trips taken by anglers (travel cost data) and on angler statements about how they would respond to changes in fishing qu...
Background Shallow nearshore marine ecosystems are changing at an increasing rate due to a range ... more Background Shallow nearshore marine ecosystems are changing at an increasing rate due to a range of human activities such as urbanisation and commercial development. As a result, an increasing number of structural modifications occur in coastal nursery and spawning habitats of fish. Concomitant to this increase, there have been declines in many coastal fish populations and changes in the composition of fish communities. As requested by Swedish stakeholders, this review aimed to synthesise scientific evidence of the impact on fish recruitment of structural modifications in temperate coastal areas. Methods We searched for peer-reviewed and grey literature on such impacts in English, Dutch, Danish, Finnish, German, Swedish and Spanish. Searches were performed in bibliographic databases, specialist websites, bibliographies of review articles. We also contacted stakeholder to find relevant literature. Eligible studies included small- and large-scale field studies in marine systems and la...
DNA barcode data hosted in the Data Portal of the Barcode of Life Data Systems. Records consist o... more DNA barcode data hosted in the Data Portal of the Barcode of Life Data Systems. Records consist of specimen metadata, specimen images, and sequence data.
Day 1 of the workshop was devoted to several lectures and shorter presentations by the participan... more Day 1 of the workshop was devoted to several lectures and shorter presentations by the participants. The lectures included three presentations on theory and techniques and four case studies (Great Lakes, Rivers, Lakes, Marine): Guy Fleischer, USGS-BRD, Ann Arbor, MI: Target strength of Great Lakes fishes John Horne: NOAA Great Lakes Laboratory, Ann Arbor, MI: Theoretical scattering models for predicting target strength and the choice of operating frequency: applications to alewife and smelt in the Great Lakes Patrick Sullivan, Cornell University, Ithaca NY: Survey design, introduction to the theory Doran Mason, Purdue University. Acoustics in Lake Superior. Kyle Hartman, West Virgnia University: Acoustics in riversthe Hudson experience Paul Walline, Lake Kinneret Laboratory, Israel: Acoustics in lakes the Lake Kinneret experience Fredrik Arrhenius, Marine Laboratory, Sweden. Acoustics in oceans -Atlantic herring in the Norwegian Sea.
Canadian Journal of Fisheries and Aquatic Sciences, 2016
Walleye (Sander vitreus), smallmouth bass (Micropterus dolomieu), and largemouth bass (Micropteru... more Walleye (Sander vitreus), smallmouth bass (Micropterus dolomieu), and largemouth bass (Micropterus salmoides) are common top predators across many north temperate lakes, but no previous analyses have assessed factors driving their combined impact on mortality of a shared prey, yellow perch (Perca flavescens). We estimated consumption dynamics of walleye, smallmouth bass, and largemouth bass during 3 years that differed in age-0 yellow perch year-class strength and evaluated the relative contribution of each predator to age-0 yellow perch mortality, in Oneida Lake, New York, USA. Habitat-specific diet composition and population densities were integrated with temperature and growth rates to parameterize a bioenergetics model and estimate annual consumption of major diet items. Walleye were the dominant predator in both offshore and inshore habitats, while smallmouth bass and largemouth bass were also important inshore predators. Consumption of age-0 yellow perch by all three predators...
Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem pro... more Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis) have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and increases in water clarity resulting in increases in benthic algae. We found that the presence of zebra mussels alone (ZM), quagga mussels alone (QM), or an equal number of both species (ZQ) reduced total phosphorus (TP) and phytoplankton Chl a. Total suspended solids (TSS) was reduced in ZM and ZQ treatments. Light intensity at the sediment surface was higher in all three mussel treatments than in the no-mussel controls but there was no difference among the mussel treatments. There was no incr...
Journal of agricultural and food chemistry, Jan 19, 2016
The fatty acid profiles of wild freshwater fish are poorly characterized as a human food source f... more The fatty acid profiles of wild freshwater fish are poorly characterized as a human food source for several classes of fatty acids, particularly for branched chain fatty acids (BCFA), a major bioactive dietary component known to enter the U.S. food supply primarily via dairy and beef fat. We evaluated the fatty acid content of 27 freshwater fish species captured in the northeastern U.S. with emphasis on the BCFA and bioactive polyunsaturated fatty acids (PUFA) most associated with fish, specifically n-3 (omega 3) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Mean BCFA content across all species were 1.0±0.5% (mean ± SD) of total fatty acids in edible muscle, with rainbow smelt (O. mordax) and pumpkinseed (L. gibbosus) the highest at >2% BCFA. In comparison, EPA+DHA constituted 28%±7% of total fatty acids. Across all fish species, the major BCFA were iso-15:0, anteiso-15:0, iso-16:0, iso-17:0 and anteiso-17:0. Fish skin had significantly higher BCFA content than musc...
Abstract The conference ‘Ecology of Fish in Lakes and Reservoirs’ (ECOFIL 2014) was held in Septe... more Abstract The conference ‘Ecology of Fish in Lakes and Reservoirs’ (ECOFIL 2014) was held in September 2014 in Ceske Budĕjovice, Czech Republic. More than 110 lectures and posters presented during the meeting documented rapid methodological developments in freshwater fisheries science and recent advances of studies of biotic integrity and quality of fish stocks required by the EU Water framework Directive and the US and Canadian Fisheries Agencies. Most contributions focused on the main conference themes of the role of fish in trophic webs, spatiotemporal patterns, effects of environmental and anthropogenic stressors, fisheries management and ecological status.
Oneida Lake, New York, is the State’s second most heavily fished body of water, receiving some 30... more Oneida Lake, New York, is the State’s second most heavily fished body of water, receiving some 300,000 angler-hours of effort annually. Walleye account for 60-80% of the targeted effort on the lake and harvest rates typically run over 90% of the legal-sized catch. With support of the New York State Department of Environmental Conservation, the Cornell Biological Field Station has monitored walleye population dynamics for 55 years. Through the 1980s, the adult walleye population fluctuated between 500,000 and 900,000 fish, and was tightly linked to yellow perch dynamics. Both angler catch rates and survival of young walleye were linked to abundance of young yellow perch, serving to stabilize the predator-prey dynamics of the lake. Beginning in the 1980s, a series of perturbations disrupted the dynamics of the system. In the late 1980s, white perch and gizzard shad, previously present at low levels, began to increase in abundance. In the early 1990s, zebra mussels colonized the lake a...
Background/Question/Methods Intra-annual survival of larval and age-0 rainbow smelt (Osmerus mord... more Background/Question/Methods Intra-annual survival of larval and age-0 rainbow smelt (Osmerus mordax) in Lake Champlain was studied in relation to adult abundance and gradients in the physical aquatic environment. Spatial dynamics of rainbow smelt are key to rainbow smelt population dynamics because this species is cannibalistic and the rate of cannibalism is a function of spatial overlap and fish density. Thus, our objective was to determine how physical environmental gradients are related to rainbow smelt distribution then determine subsequent cannibalism rates and mortality of young fish. Using day and night hydroacoustic data from 2007 and 2008, we created generalized additive mixed effects models to predict rainbow smelt vertical distribution as a function of temperature and light. We compared predicted and observed cannibalism and subsequent mortality of age-0 fish as a function of fish distribution. Results/Conclusions We found highest intra-annual mortality occurred during sp...
To better understand, and subsequently reduce, uncertainty in pelagic fish population data, analy... more To better understand, and subsequently reduce, uncertainty in pelagic fish population data, analyses were conducted on simultaneously-collected trawl and hydroacoustic data from over 200 sampling events in Lake Champlain, a mesotrophic freshwater lake located between New York (USA), Vermont (USA), and Quebec (Canada). A model set, which used a number of factors to explore sources of variance, was analyzed. Factors explored were acoustic density estimation method, sampling time, sampling season, water temperature, light, invertebrate presence, fish size, fish species, and collection depth. Trawl avoidance was higher during the day, and varied with trawl type. Sources of variance in hydroacoustic estimates were the size and depth of analysis regions, presence of invertebrates, and fish shoaling behavior. All fish species could not be differentiated using acoustic target strength, thus necessitating trawl collections to estimate species-specific abundance. Trawl collection showed verti...
Recent declines in epilimnetic nutrients and zooplankton biomass have resulted in a shift towards... more Recent declines in epilimnetic nutrients and zooplankton biomass have resulted in a shift towards deeper production in Lake Ontario. As a result, there has been an increase in the deep chlorophyll layer (DCL) during the stratified period. In turn, zooplankton grazing and subsequent nutrient regeneration may occur at deeper depths, possibly affecting the production of planktivorous fishes and invertebrates. Given Lake Ontario’s reliance on Alewife to sustain salmonid fisheries, understanding tropic shifts in food webs is of particular importance. In this study we used a diel approach to describe trophic interactions of planktivores and their prey within and around Lake Ontario’s DCL during 2013. During spring mysids appear to graze heavily on diatoms, but in July and September mysids switch to zooplanktivory and compete with Alewife and Rainbow Smelt for prey. The predatory impact of the invasive spiny water flea Bythotrephes was minimal in Lake Ontario during 2013. Bythotrephes abun...
Zooplankton biomass has decreased an order of magnitude in the offshore epilimnion of Lake Ontari... more Zooplankton biomass has decreased an order of magnitude in the offshore epilimnion of Lake Ontario during the last decade, with the largest decreases in smaller zooplankton (Bosmina and Diacyclops). These decreases cannot be attributed to alewife planktivory, because alewife has declined during this time period. However, the invasive predatory cladoceran Bythotrephes has increased since 2005 which may be a result of decreased alewife planktivory. Other invertebrate predators include the cladocerans Cercopagis, Leptodora and Polyphemus, several copepods (e.g. Limnocalanus), and the mysid Mysis diluviana (relicta). We analyze the time trends in zooplanktivory from these invertebrates from 2000 to 2010 using bioenergetics models. Zooplanktivory by invertebrates increased due to the increase in Bythotrephes although Mysis continues to be important. The role of omnivores like Limnocalanus is increasing. Understanding recent changes in zooplankton abundance and community composition in La...
ABSTRACT Mysid shrimp are important both as predators on zooplankton and as prey for a variety of... more ABSTRACT Mysid shrimp are important both as predators on zooplankton and as prey for a variety of fish species across most of the Laurentian Great Lakes. In Lake Champlain, where little is known about mysids, this may also be true. We evaluated the role of Mysis diluviana as a planktivore in Lake Champlain using hydroacoustics, gut content analysis, stable isotopes, cohort analysis, and bioenergetics models to estimate Mysis density, diets, growth rates, and prey consumption rates. Density of Mysis in the water column of the deeper Main Lake was lower in July–August of 2008–2011 (38, 38, 21, and 74 Mysis/m2, respectively) than historical values from the 1970s. Mysis selectively foraged for cladocerans, but also consumed cyclopoid and calanoid copepods in 2011. Stable isotope data suggest a mostly carnivorous diet, although agreement between isotope mixing models and observed diets varied. Cohort analyses revealed growth rates ranging from 2.7 mm/month in late spring to 1.3 mm/month in late summer. In contrast to the offshore areas of Lake Ontario and Lake Huron, zooplankton consumption by the Mysis population was low relative to zooplankton density and production indicating that Mysis are not currently a major zooplanktivore in Lake Champlain.
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