ABSTRACT Since the 1970s, significant QX disease outbreaks have taken place in Sydney rock oyster... more ABSTRACT Since the 1970s, significant QX disease outbreaks have taken place in Sydney rock oyster (Saccostrea glomerata)producing estuaries in New South Wales, Australia, devastating production. Despite research efforts, there are still many gaps in our knowledge of QX disease (causative agent: Marteilia sydneyi). A better understanding of the timing and triggers of the QX infection would allow the management of oyster farms to be tailored to address the high-risk period. This study examined the extent and variability of the QX window of infection across multiple years (2005/2006 to 2008/2009) in the Hawkesbury River and characterized environmental conditions prior to, during, and after the infection window during these years. The window of QX infection onset across the years was found to be highly variable, with start times occurring between November and February, whereas the infection termination time was more defined, occurring within the first week in April, except in 2006/2007, which ceased during the last week of April. The termination of the infection window occurred during a significant decrease in water temperature (at a rate of 3.7°C/mo), with no infection occurring at water temperatures less than 21.5°C Environmental conditions were more variable at the onset of the infection window, when water temperatures showed high levels of variability among years as a result of cool freshwater inputs from rainfall events, which occur commonly at this time of year. These freshwater inputs also resulted in significant decreases in salinity levels (to at least ∼10 ppt), which may be an additional factor influencing QX disease outbreaks. Previous QX work suggested an infection period of 19 days; here, longer infection periods were observed and lasted between 8 wk and 18 wk, depending on the year.
The task of defining, monitoring and reporting estuarine condition is complex. This task requires... more The task of defining, monitoring and reporting estuarine condition is complex. This task requires choosing one or many condition indicators which may indicate physical, chemical, ecotoxicological and ecological conditions of an estuary. There is no single indicator that defines the condition of an estuary. The choice of an indicator depends on the estuarine values or uses of the estuary that are to be protected (environmental values) and numeric or descriptive statements that must be met within a specified timeframe to protect and maintain the estuarine values and uses (environmental targets). To assist local government with estuarine condition assessment, guidance is provided from the NSW State Government, Office of Environment and Heritage (OEH) which sets protocols for monitoring water quality, estuarine macrophytes, fish assemblage and other indicators (NSW Government 2013). In this paper, OEH condition indicators for water quality (chlorophyll-a and turbidity) are used to assig...
There have been many individual phytoplankton datasets collected across Australia since the mid 1... more There have been many individual phytoplankton datasets collected across Australia since the mid 1900s, but most are unavailable to the research community. We have searched archives, contacted researchers, and scanned the primary and grey literature to collate 3,621,847 records of marine phytoplankton species from Australian waters from 1844 to the present. Many of these are small datasets collected for local questions, but combined they provide over 170 years of data on phytoplankton communities in Australian waters. Units and taxonomy have been standardised, obviously erroneous data removed, and all metadata included. We have lodged this dataset with the Australian Ocean Data Network (http://portal.aodn.org.au/) allowing public access. The Australian Phytoplankton Database will be invaluable for global change studies, as it allows analysis of ecological indicators of climate change and eutrophication (e.g., changes in distribution; diatom:dinoflagellate ratios). In addition, the st...
Chlorophyll a is the most commonly used indicator of phytoplankton biomass in the marine environm... more Chlorophyll a is the most commonly used indicator of phytoplankton biomass in the marine environment. It is relatively simple and cost effective to measure when compared to phytoplankton abundance and is thus routinely included in many surveys. Here we collate 173, 333 records of chlorophyll a collected since 1965 from Australian waters gathered from researchers on regular coastal monitoring surveys and ocean voyages into a single repository. This dataset includes the chlorophyll a values as measured from samples analysed using spectrophotometry, fluorometry and high performance liquid chromatography (HPLC). The Australian Chlorophyll a database is freely available through the Australian Ocean Data Network portal (https://portal.aodn.org.au/). These data can be used in isolation as an index of phytoplankton biomass or in combination with other data to provide insight into water quality, ecosystem state, and relationships with other trophic levels such as zooplankton or fish.
Abstract: Throughout the world, water management and planning issues are becoming increasingly di... more Abstract: Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory ...
Progress towards climate change aware regional sustainable development is affected by actions at ... more Progress towards climate change aware regional sustainable development is affected by actions at multiple spatial scales and governance levels and equally impacts actions at these scales. Many authors and policy practitioners consider therefore that decisions over policy, mitigation strategies and capacity for adaptation to climate change require construction and coordination over multiple levels of governance to arrive at acceptable local,
Abstract: Throughout the world, water management and planning issues are becoming increasingly di... more Abstract: Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory ...
Abstract: Throughout the world, water management and planning issues are becoming increasingly di... more Abstract: Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory ...
Progress towards climate change aware regional sustainable development is affected by actions at ... more Progress towards climate change aware regional sustainable development is affected by actions at multiple spatial scales and governance levels and equally impacts actions at these scales. Many authors and policy practitioners consider therefore that decisions over policy, mitigation strategies and capacity for adaptation to climate change require construction and coordination over multiple levels of governance to arrive at acceptable local,
ABSTRACT Since the 1970s, significant QX disease outbreaks have taken place in Sydney rock oyster... more ABSTRACT Since the 1970s, significant QX disease outbreaks have taken place in Sydney rock oyster (Saccostrea glomerata)producing estuaries in New South Wales, Australia, devastating production. Despite research efforts, there are still many gaps in our knowledge of QX disease (causative agent: Marteilia sydneyi). A better understanding of the timing and triggers of the QX infection would allow the management of oyster farms to be tailored to address the high-risk period. This study examined the extent and variability of the QX window of infection across multiple years (2005/2006 to 2008/2009) in the Hawkesbury River and characterized environmental conditions prior to, during, and after the infection window during these years. The window of QX infection onset across the years was found to be highly variable, with start times occurring between November and February, whereas the infection termination time was more defined, occurring within the first week in April, except in 2006/2007, which ceased during the last week of April. The termination of the infection window occurred during a significant decrease in water temperature (at a rate of 3.7°C/mo), with no infection occurring at water temperatures less than 21.5°C Environmental conditions were more variable at the onset of the infection window, when water temperatures showed high levels of variability among years as a result of cool freshwater inputs from rainfall events, which occur commonly at this time of year. These freshwater inputs also resulted in significant decreases in salinity levels (to at least ∼10 ppt), which may be an additional factor influencing QX disease outbreaks. Previous QX work suggested an infection period of 19 days; here, longer infection periods were observed and lasted between 8 wk and 18 wk, depending on the year.
The task of defining, monitoring and reporting estuarine condition is complex. This task requires... more The task of defining, monitoring and reporting estuarine condition is complex. This task requires choosing one or many condition indicators which may indicate physical, chemical, ecotoxicological and ecological conditions of an estuary. There is no single indicator that defines the condition of an estuary. The choice of an indicator depends on the estuarine values or uses of the estuary that are to be protected (environmental values) and numeric or descriptive statements that must be met within a specified timeframe to protect and maintain the estuarine values and uses (environmental targets). To assist local government with estuarine condition assessment, guidance is provided from the NSW State Government, Office of Environment and Heritage (OEH) which sets protocols for monitoring water quality, estuarine macrophytes, fish assemblage and other indicators (NSW Government 2013). In this paper, OEH condition indicators for water quality (chlorophyll-a and turbidity) are used to assig...
There have been many individual phytoplankton datasets collected across Australia since the mid 1... more There have been many individual phytoplankton datasets collected across Australia since the mid 1900s, but most are unavailable to the research community. We have searched archives, contacted researchers, and scanned the primary and grey literature to collate 3,621,847 records of marine phytoplankton species from Australian waters from 1844 to the present. Many of these are small datasets collected for local questions, but combined they provide over 170 years of data on phytoplankton communities in Australian waters. Units and taxonomy have been standardised, obviously erroneous data removed, and all metadata included. We have lodged this dataset with the Australian Ocean Data Network (http://portal.aodn.org.au/) allowing public access. The Australian Phytoplankton Database will be invaluable for global change studies, as it allows analysis of ecological indicators of climate change and eutrophication (e.g., changes in distribution; diatom:dinoflagellate ratios). In addition, the st...
Chlorophyll a is the most commonly used indicator of phytoplankton biomass in the marine environm... more Chlorophyll a is the most commonly used indicator of phytoplankton biomass in the marine environment. It is relatively simple and cost effective to measure when compared to phytoplankton abundance and is thus routinely included in many surveys. Here we collate 173, 333 records of chlorophyll a collected since 1965 from Australian waters gathered from researchers on regular coastal monitoring surveys and ocean voyages into a single repository. This dataset includes the chlorophyll a values as measured from samples analysed using spectrophotometry, fluorometry and high performance liquid chromatography (HPLC). The Australian Chlorophyll a database is freely available through the Australian Ocean Data Network portal (https://portal.aodn.org.au/). These data can be used in isolation as an index of phytoplankton biomass or in combination with other data to provide insight into water quality, ecosystem state, and relationships with other trophic levels such as zooplankton or fish.
Abstract: Throughout the world, water management and planning issues are becoming increasingly di... more Abstract: Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory ...
Progress towards climate change aware regional sustainable development is affected by actions at ... more Progress towards climate change aware regional sustainable development is affected by actions at multiple spatial scales and governance levels and equally impacts actions at these scales. Many authors and policy practitioners consider therefore that decisions over policy, mitigation strategies and capacity for adaptation to climate change require construction and coordination over multiple levels of governance to arrive at acceptable local,
Abstract: Throughout the world, water management and planning issues are becoming increasingly di... more Abstract: Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory ...
Abstract: Throughout the world, water management and planning issues are becoming increasingly di... more Abstract: Throughout the world, water management and planning issues are becoming increasingly difficult to handle, and there have been calls for more adapted approaches to aid the decision-making processes required for water planning and management. Participatory ...
Progress towards climate change aware regional sustainable development is affected by actions at ... more Progress towards climate change aware regional sustainable development is affected by actions at multiple spatial scales and governance levels and equally impacts actions at these scales. Many authors and policy practitioners consider therefore that decisions over policy, mitigation strategies and capacity for adaptation to climate change require construction and coordination over multiple levels of governance to arrive at acceptable local,
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Papers by Peter Coad