Latest news with #Karenia
The Advertiser
08-07-2025
- Climate
- The Advertiser
'Toxic to anything with gills': algal bloom spreading
A massive, toxic algal bloom that has killed thousands of fish, sharks and marine animals has spread to a capital city river. The bloom of the microalgae, karenia mikimotoi, was identified off South Australia's Fleurieu Peninsula in March, and grew to more than 4400 sq km, close to the size of Kangaroo Island. It has been breaking up in recent weeks, spreading north into Spencer Gulf, south into the Coorong wetlands and along Adelaide's beaches in Gulf St Vincent. SA Environment Minister Susan Close said the "devastating" bloom had now been detected in Adelaide's Port River. "Karenia mikimotoi has appeared in the Port River and is at reasonably high concentrations around Garden Island and Outer Harbour," she told reporters on Tuesday. "Nothing near like the concentrations that we saw at the beginning of this bloom ... but nonetheless elevated amounts." Ms Close said the algae had killed tens of thousands of marine animals from almost 400 species, and authorities were concerned some may be wiped out in the region. "Although not toxic to humans, it is toxic to anything with gills and anything that seeks to breathe underwater, and we have seen just the beginnings of the extent of the devastation that's occurred under the sea," she said. SA Primary Industries and Regional Development Minister Clare Scriven said the government had started talks with the Commonwealth about recovery assistance. It is not possible for the federal government to declare the incident a national disaster because the definition does not currently include algal blooms, she said. The SA government announced backdated licence fee relief for commercial fishers, aquaculture and charter boat operators impacted by the bloom. About $500,000 worth of fees will be waived to help operators, with a promise that more help will be available if needed. SA Professional Fishers Association chair Ben Barnes said some fishers reported seeing "absolute destruction of the environment" and the industry was yet to see the worst of the disaster. "It will be a recurring thing that we just won't know for the next five to six years," he said. "The extent of the devastation is unknown ... it will have an effect on larvae and eggs and production." Experts believe there are three potential contributing factors causing the bloom. One is a marine heatwave that started in September 2024, with sea temperatures about 2.5C warmer than usual, combined with calm conditions, light winds and small swells. Another is the 2022/23 River Murray flood that washed extra nutrients into the sea. That was followed by an unprecedented cold-water upwelling in summer of 2023/24 that brought nutrient-rich water to the surface. A massive, toxic algal bloom that has killed thousands of fish, sharks and marine animals has spread to a capital city river. The bloom of the microalgae, karenia mikimotoi, was identified off South Australia's Fleurieu Peninsula in March, and grew to more than 4400 sq km, close to the size of Kangaroo Island. It has been breaking up in recent weeks, spreading north into Spencer Gulf, south into the Coorong wetlands and along Adelaide's beaches in Gulf St Vincent. SA Environment Minister Susan Close said the "devastating" bloom had now been detected in Adelaide's Port River. "Karenia mikimotoi has appeared in the Port River and is at reasonably high concentrations around Garden Island and Outer Harbour," she told reporters on Tuesday. "Nothing near like the concentrations that we saw at the beginning of this bloom ... but nonetheless elevated amounts." Ms Close said the algae had killed tens of thousands of marine animals from almost 400 species, and authorities were concerned some may be wiped out in the region. "Although not toxic to humans, it is toxic to anything with gills and anything that seeks to breathe underwater, and we have seen just the beginnings of the extent of the devastation that's occurred under the sea," she said. SA Primary Industries and Regional Development Minister Clare Scriven said the government had started talks with the Commonwealth about recovery assistance. It is not possible for the federal government to declare the incident a national disaster because the definition does not currently include algal blooms, she said. The SA government announced backdated licence fee relief for commercial fishers, aquaculture and charter boat operators impacted by the bloom. About $500,000 worth of fees will be waived to help operators, with a promise that more help will be available if needed. SA Professional Fishers Association chair Ben Barnes said some fishers reported seeing "absolute destruction of the environment" and the industry was yet to see the worst of the disaster. "It will be a recurring thing that we just won't know for the next five to six years," he said. "The extent of the devastation is unknown ... it will have an effect on larvae and eggs and production." Experts believe there are three potential contributing factors causing the bloom. One is a marine heatwave that started in September 2024, with sea temperatures about 2.5C warmer than usual, combined with calm conditions, light winds and small swells. Another is the 2022/23 River Murray flood that washed extra nutrients into the sea. That was followed by an unprecedented cold-water upwelling in summer of 2023/24 that brought nutrient-rich water to the surface. A massive, toxic algal bloom that has killed thousands of fish, sharks and marine animals has spread to a capital city river. The bloom of the microalgae, karenia mikimotoi, was identified off South Australia's Fleurieu Peninsula in March, and grew to more than 4400 sq km, close to the size of Kangaroo Island. It has been breaking up in recent weeks, spreading north into Spencer Gulf, south into the Coorong wetlands and along Adelaide's beaches in Gulf St Vincent. SA Environment Minister Susan Close said the "devastating" bloom had now been detected in Adelaide's Port River. "Karenia mikimotoi has appeared in the Port River and is at reasonably high concentrations around Garden Island and Outer Harbour," she told reporters on Tuesday. "Nothing near like the concentrations that we saw at the beginning of this bloom ... but nonetheless elevated amounts." Ms Close said the algae had killed tens of thousands of marine animals from almost 400 species, and authorities were concerned some may be wiped out in the region. "Although not toxic to humans, it is toxic to anything with gills and anything that seeks to breathe underwater, and we have seen just the beginnings of the extent of the devastation that's occurred under the sea," she said. SA Primary Industries and Regional Development Minister Clare Scriven said the government had started talks with the Commonwealth about recovery assistance. It is not possible for the federal government to declare the incident a national disaster because the definition does not currently include algal blooms, she said. The SA government announced backdated licence fee relief for commercial fishers, aquaculture and charter boat operators impacted by the bloom. About $500,000 worth of fees will be waived to help operators, with a promise that more help will be available if needed. SA Professional Fishers Association chair Ben Barnes said some fishers reported seeing "absolute destruction of the environment" and the industry was yet to see the worst of the disaster. "It will be a recurring thing that we just won't know for the next five to six years," he said. "The extent of the devastation is unknown ... it will have an effect on larvae and eggs and production." Experts believe there are three potential contributing factors causing the bloom. One is a marine heatwave that started in September 2024, with sea temperatures about 2.5C warmer than usual, combined with calm conditions, light winds and small swells. Another is the 2022/23 River Murray flood that washed extra nutrients into the sea. That was followed by an unprecedented cold-water upwelling in summer of 2023/24 that brought nutrient-rich water to the surface. A massive, toxic algal bloom that has killed thousands of fish, sharks and marine animals has spread to a capital city river. The bloom of the microalgae, karenia mikimotoi, was identified off South Australia's Fleurieu Peninsula in March, and grew to more than 4400 sq km, close to the size of Kangaroo Island. It has been breaking up in recent weeks, spreading north into Spencer Gulf, south into the Coorong wetlands and along Adelaide's beaches in Gulf St Vincent. SA Environment Minister Susan Close said the "devastating" bloom had now been detected in Adelaide's Port River. "Karenia mikimotoi has appeared in the Port River and is at reasonably high concentrations around Garden Island and Outer Harbour," she told reporters on Tuesday. "Nothing near like the concentrations that we saw at the beginning of this bloom ... but nonetheless elevated amounts." Ms Close said the algae had killed tens of thousands of marine animals from almost 400 species, and authorities were concerned some may be wiped out in the region. "Although not toxic to humans, it is toxic to anything with gills and anything that seeks to breathe underwater, and we have seen just the beginnings of the extent of the devastation that's occurred under the sea," she said. SA Primary Industries and Regional Development Minister Clare Scriven said the government had started talks with the Commonwealth about recovery assistance. It is not possible for the federal government to declare the incident a national disaster because the definition does not currently include algal blooms, she said. The SA government announced backdated licence fee relief for commercial fishers, aquaculture and charter boat operators impacted by the bloom. About $500,000 worth of fees will be waived to help operators, with a promise that more help will be available if needed. SA Professional Fishers Association chair Ben Barnes said some fishers reported seeing "absolute destruction of the environment" and the industry was yet to see the worst of the disaster. "It will be a recurring thing that we just won't know for the next five to six years," he said. "The extent of the devastation is unknown ... it will have an effect on larvae and eggs and production." Experts believe there are three potential contributing factors causing the bloom. One is a marine heatwave that started in September 2024, with sea temperatures about 2.5C warmer than usual, combined with calm conditions, light winds and small swells. Another is the 2022/23 River Murray flood that washed extra nutrients into the sea. That was followed by an unprecedented cold-water upwelling in summer of 2023/24 that brought nutrient-rich water to the surface.
Sky News AU
07-07-2025
- Health
- Sky News AU
'They will lie and wait': Algal blooms on South Australia coast could make people 'very sick', as marine life washes ashore along the state's coastline
Future algae blooms across South Australia could be harmful to humans an expert has warned, as the state continues to battle through a marine crisis. South Australian beaches have been awash with foamy, discoloured water and dead marine life for months, a result of a microalgae called Karenia mikimotoi. There are multiple types of dinoflagellate algae, including Karenia mikimotoi, researcher and conservationist Mike Bossley told Sky News, and some 'do effect mammals'. 'In California at the moment there is an algal bloom which is affecting mostly seals and sea lions,' he said. 'They are attacking people on beaches; it makes them very aggressive. 'It is killing other marine life like dolphins as well'. The algae bloom off the California coast has been on the rise in recent years, producing a neurological toxin called domoic acid, which when ingested in large quantities attacks an animal's brain and heart, which can lead to seizures and heart failure. In humans, direct exposure has been reported to cause gastrointestinal and neurological issues. 'I don't think it would actually kill someone, but it would certainly make them very sick,' Dr Bossley said. A combination of calm warm conditions and excess nutrients has allowed the current algal bloom to grow across the South Australian coast, stretching along the Fleurieu Peninsula, Yorke Peninsula, Kangaroo Island, and reaching the metropolitan beaches in recent weeks. If those conditions continue, Dr Bossley warned any type of microalgae may develop on the state's coast. 'What I have been able to discover is sea temperatures are about 2C warmer than usual,' he said. 'This time it was Karenia, next time it could be another. 'From time to time any of them just explodes in their numbers and out breeds anything else.' The current algae impacting South Australia irritates fish gills and can lead to a lack of oxygen in the blood. The phenomenon has led to marine life washing shore along the state coast, a sight that could continue for the next 12 months, experts warn. Scientists were hoping that a drop in temperatures over winter would bring an end to the ecological disaster, but Environment Minister Susan Close wants to "prepare people" that the bloom is "not something that is likely to pass quickly". She has explained in recent weeks that Karenia mikimotoi can drop to the seabed and survive if the conditions are no longer suited it. "They will lie and wait, so, we should at least prepare ourselves for the likelihood that when the conditions return in the future, we will see other blooms," she said. The Greens have announced they will establish an urgent inquiry into the marine crisis when parliament returns on July 22, following reports that the Federal Government has rejected calls for funding.
Perth Now
04-07-2025
- Climate
- Perth Now
Algal bloom turns coast into a 'marine graveyard'
A massive, unstoppable, toxic algal bloom that has turned beaches into "marine graveyards" has prompted calls for a federal investigation. The microalgae, karenia mikimotoi, was identified off South Australia's Fleurieu Peninsula in March. The bloom grew to an unprecedented scale, close to the size of Kangaroo Island, at more than 4400 sq km, and as deep as 25m. It's now breaking up and has spread into most of Gulf St Vincent, including along Adelaide's beaches and south into the Coorong wetlands. There have been hundreds of reports of marine deaths, ranging from sharks and penguins to popular fishing species such as flathead, squid, crabs, and rock lobsters. Greens senator Sarah Hanson-Young said the bloom was a horrific and heartbreaking "environmental catastrophe". "When parliament resumes in two weeks time in Canberra, I will be moving for a federal parliamentary inquiry," she told reporters on Friday. "We need proper investigation and proper federal support." Beaches have become "graveyards" for marine species, and the fishing and tourism industries have been significantly impacted, she said. Ms Hanson-Young claimed the federal government ignored warnings about the algae before it took hold. "It is very concerning that the country's leading marine scientists have been ignored and dismissed," she said. Experts believe there are three potential plausible contributing factors causing the bloom, the SA government said. One is a marine heatwave that started in September 2024, with sea temperatures about 2.5°C warmer than usual, combined with calm conditions, light winds and small swells. Another is the 2022-23 River Murray flood washing extra nutrients into the sea and an unprecedented cold-water upwelling in summer 2023-24 that brought nutrient-rich water to the surface. SA Environment Minister Susan Close said the bloom had lasted longer than experts thought it would. "Now that it's here, it's going to be hard to get rid of," she said. "It's easy to feel helpless, because the bloom itself is something that we can't stop." The SA government met with impacted commercial fishers, tourism operators and local councils about support packages. "It's been very, very distressing for people, and it's affected people's livelihoods," Ms Close said. The state government is also starting work on a recovery plan. This could include creating artificial reefs to help build up marine life, restocking fish into the ocean and increasing the number of marine sanctuary zones along the coast. "Although we're looking forward to the end of this experience, we cannot assume it's the last time we've had it," Ms Close said. Karenia mikimotoi is in SA's waterways and waiting to come back to life when conditions are right, she said. "This is what climate change means." OzFish previously said more than 200 species of fish, sharks and other marine creatures had been killed by the algae bloom. This includes rarely encountered deepwater sharks and leafy sea dragons, and recreational fishing species like flathead, squid, crabs, and rock lobsters. Karenia mikimotoi is toxic to fish and invertebrates but does not cause long-term harmful effects in humans. But, exposure to discoloured or foamy water can cause short-term skin or eye irritation and respiratory symptoms, including coughing or shortness of breath. The last large event of this type of algae recorded in SA was at Coffin Bay in 2014.
7NEWS
03-06-2025
- Business
- 7NEWS
South Australia's Coorong at risk as algae outbreak puts fragile ecosystem on the brink
The toxic algae bloom that has plagued South Australian coastlines since March has, 'unfortunately,' made its way into one of the state's most fragile ecosystems — the Coorong. Last week's powerful storm surge was initially welcomed, with hopes it would push cold, salty ocean water onto the shore to disrupt the bloom of the toxic micro-algae karenia mikimotoi algae. However, those same strong currents instead drove the algae back up the Murray River at Goolwa, entering the Coorong through the Murray Mouth — where the river meets the Southern Ocean. With ongoing drought conditions and tidal influences, the algae has now found an ideal environment in which it may be impossible to remove. Previously responsible for murky waters and thick sea foam along the Fleurieu Peninsula, Karenia mikimotoi is also suspected to be linked to the recent deaths of several sharks on Adelaide beaches. Ecologist and Coorong Environmental Trustee Faith Coleman expressed grave concern about the algae's intrusion into the Coorong's intricate ecosystem. 'Unfortunately, that amazing storm tide managed to push the Karenia straight into the northern lagoon of the Coorong, where it is blooming quite happily,' she said. 'Because of the unique nature of coastal lagoons, once something gets in, it rarely gets out.' The algae has now established itself in a 'sweet spot' at the end of the northern lagoon, where conditions — including high salinity, warm temperatures, and stagnant water — are perfect for it to thrive. Up to two metres of decomposing marine life, described as 'worm soup,' has already been found, with dead tubeworms and larvae washing ashore. Experts warn this could disrupt the already delicate food chain in the area. 'Many of the small organisms at the base of the food chain — those vital to shorebirds and fish — are now washing up dead,' Coleman said. 'There isn't anything that lives or grows in the water of the Coorong that is safe from this.' Local fisherman Glen Hill, owner of Coorong Wild Seafood, said the situation could devastate the region's fishing industry. 'I've bashed my head against the side of the chiller in frustration. I've cried my eyes out,' Hill told 7NEWS. 'If we lose the bottom of the food chain, what do the fish eat? 'Potentially, we could lose everything.' The storm system also stirred up sediment and, combined with the lack of fresh water, has spiked salinity levels in the Coorong. This has led to further environmental stress, with fish such as mullet, mulloway, and bony bream suffering visible gill damage — likely caused by the increasingly toxic conditions. The Department of Primary Industries and Regions (PIRSA) confirmed they are investigating recent fish deaths but have not yet officially linked them to Karenia mikimotoi. 'We continue to work with other relevant government agencies on the current Karenia species algal bloom and associated fish deaths that have been occurring in South Australian waters since March,' a PIRSA spokesperson said in a statement to 7NEWS. Investigations are underway into reports of a bony bream fish kill in Woods Well Bay and a polychaete worm die-off near Long Point. Water samples have been collected and results are pending. 'Our role is to investigate any infectious or notifiable animal diseases that may have caused the fish deaths,' PIRSA said. The Department for Environment and Water (DEW) also confirmed the algae's entry into the Coorong was a known risk — and that any intervention, such as opening the barrages to flush water, could worsen the situation. 'The Coorong is open to the sea via the Murray Mouth and cannot be closed off from the ocean,' a DEW spokesperson said. 'During adverse weather and high tides, SA Water operates the barrages to minimise seawater entering Lake Alexandrina and to limit salinity impacts from reverse flows.' They added that although the tide pushed the algae in, the Coorong's natural connection to the Murray Mouth meant this could not be prevented. 'Pushing more water through the barrages to try to flush out the algae is unlikely to be effective and could risk spreading the bloom further south,' the spokesperson said. DEW confirmed it will continue monitoring the Coorong's northern lagoon and reaffirmed the State Government's commitment to protecting the area's ecological health. In the meantime, PIRSA and SA Health have advised the public not to collect or eat any dead or dying fish or marine organisms found along the shore. To report unusual sightings of fish kills or affected marine life, residents are urged to contact FISHWATCH on 1800 065 522. Concerns about water quality can be reported to the EPA at 1800 623 445 or by emailing yourepa@
Express Tribune
13-05-2025
- Health
- Express Tribune
South Australia hit by mass deaths of fish, sharks and octopuses due to toxic algae: Research says
Photo: Algal bloom become the reason for marine life death in South Australia Listen to article A toxic algal bloom stretching along South Australia's coastline since March has killed more than 200 marine species, including sharks, leafy sea dragons and octopuses, researchers said. The bloom, caused by the harmful algae "Karenia mikimotoi", has acted like a 'toxic blanket', suffocating marine life, said Brad Martin, South Australian project manager at OzFish, a conservation group. Analysis of more than 1,400 citizen scientist reports by OzFish found that 47% of the species killed were ray-finned fish, while 26% were sharks and rays. Cephalopods such as squid, cuttlefish and octopuses accounted for 7% of the casualties, while decapods – including crabs, lobsters and prawns – made up a further 6%. 'This type of bloom creates a low-oxygen environment, and marine animals simply cannot escape it,' Martin said. Karenia blooms are rare but deadly, releasing toxins and depleting oxygen levels in affected waters. Scientists say changing ocean conditions may be fuelling more frequent and severe outbreaks. Coastal communities and fisheries have reported widespread beach strandings, with some species never before seen in such numbers in die-offs. Local environmental groups have called for increased monitoring and long-term marine health strategies as ocean temperatures rise. 'It can choke fish by blocking their gills, trigger internal bleeding by damaging red blood cells, and act as a neurotoxin that disrupts the brain and nervous system, leading to erratic behaviour,' he said. 'That's why some fish and sharks have been behaving abnormally, and why many of the dead animals appear reddish – it's like a horror scene beneath the waves.' South Australia's environment department said the algal bloom is being fuelled by a prolonged marine heatwave, with sea temperatures around 2.5 degrees Celsius above average, combined with calm seas, low wind, and minimal swell. Though not harmful to humans, the algae can trigger skin irritation and respiratory issues, and has led to widespread marine deaths. First detected in mid-March off the Fleurieu Peninsula, the bloom has since spread to coastal areas across the state's south-east, including the Gulf St Vincent, Yorke Peninsula and Kangaroo Island, according to OzFish's Brad Martin. OzFish, a group focused on restoring aquatic ecosystems, expressed concern over the long-term consequences for fisheries, as the bloom has affected fish of all life stages – from juveniles to mature, breeding adults – along with their natural prey. South Australia's environment minister, Susan Close, said several oyster farms and commercial pipi harvesting operations had been suspended due to the outbreak, calling it an unprecedented event for the state. 'This is a major algal bloom with serious effects on marine species,' she said, adding that in some areas, the bloom has penetrated as deep as 20 metres. Professor Shauna Murray, a marine biologist at the University of Technology Sydney who identified the algae using microscopy and DNA analysis, said around 100 species of harmful algae are known globally, each with distinct toxic impact. Although not yet fully understood, Karenia mikimotoi is believed to release a reactive form of oxygen that damages fish gill cells, effectively suffocating them, said Professor Shauna Murray. The current bloom spans more than 150 kilometres along the coast, but it is not the largest recorded in Australia. In 2013, a different algal species, Alexandrium catenella, covered Tasmania's entire east coast, halting aquaculture and seafood operations for nearly four months, Murray added. Large-scale algal blooms can also reduce oxygen levels in the water, said Professor Martina Doblin, an oceanographer at the University of Technology Sydney who specialises in harmful algal events. Karenia mikimotoi is unusual, Doblin explained, in that it can draw energy from both sunlight and feeding on other organisms. This dual capability, combined with abnormally warm and stable ocean temperatures, has allowed the bloom to expand and persist over time. 'At low levels, it forms part of the natural food chain. But when it grows in large concentrations, it becomes a serious threat,' she said. Though rare, such blooms can have serious consequences for local economies. Doblin said better early warning and response systems could help minimise the impact of future outbreaks. A spokesperson for South Australia's environment department said strong westerly winds are needed to disperse the algae. However, the presence of ongoing high-pressure systems across southern Australia has delayed the arrival of those wind.
