A harmful algal bloom (HAB) is a biological process in which certain phytoplankton, cyanobacteria, or macroalgae proliferate rapidly and reach high biomass, producing adverse ecological or health effects via toxin production, hypoxia, or habitat alteration. HABs are driven by interactions among nutrient enrichment (especially nitrogen and phosphorus), light, temperature, hydrography, and species-specific physiology, often resulting in dominance of toxin-producing taxa such as some dinoflagellates, diatoms, or cyanobacteria. These blooms can disrupt food webs, cause mass mortalities of aquatic organisms, and generate bioaccumulated toxins that affect higher trophic levels, including humans, through consumption or exposure.
Toxic algal blooms are of increasing concern in Australia, with South Australia's coastal waters feeling their impacts in the form of damaged marine environments and widespread fish deaths since early 2025.
Ecology
Dec 9, 2025
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South Australians are suddenly hearing a lot about oyster reefs—from government, on the news and in conversations, both online and in person. It's not accidental.
Plants & Animals
Dec 9, 2025
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A microscopic organism linked to serious seafood-related illness has been detected for the first time in the waters of Hervey Bay and Gladstone. The findings are published in Harmful Algae. Joseph Perkins, a James Cook University ...
Ecology
Dec 2, 2025
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An underwater bloom of toxic algae has wreaked havoc off the coast of South Australia since mid-March 2025. After eight months, this harmful algal bloom is the longest and one of the most environmentally devastating events ...
Ecology
Nov 20, 2025
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In a significant step toward dealing with the persistent harmful algal bloom affecting the South Australian coast, researchers have identified the species chiefly responsible for mass deaths of marine animals and potential ...
Ecology
Nov 13, 2025
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A long-term analysis shows that a major Oregon reservoir abruptly swapped one type of toxic algae for another midway through the 12-year study period, absent any obvious cause. The project provides a novel look at harmful ...
Ecology
Nov 11, 2025
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Beneath the surface of lakes and coastal waters lies a hidden world of sediment that plays a crucial role in the health of aquatic ecosystems. "Benthic fluxes" of nitrogen and phosphorus, such as releases of these dissolved ...
Earth Sciences
Nov 5, 2025
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13
In the summer of 2022, toxins produced by the brackish-water algae Prymnesium parvum killed about 1,000 metric tons of fish, snails, and mussels in the River Oder. In a study published in the journal Ecotoxicology and Environmental ...
Plants & Animals
Oct 2, 2025
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For the third year running toxic blue-green algae blooms that look like pea soup and smell like rotten eggs have covered much of Lough Neagh, the largest lake in the UK and Ireland.
Environment
Sep 14, 2025
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279
Amid toxic algal blooms in South Australia and mass fish deaths across the country, a new piece of technology designed by one of Perth's leading marine scientists may hold a solution.
Ecology
Sep 8, 2025
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