Waters from last year’s floods in Australia’s southeast are gushing out to sea and taking carp with them — but the salinity of the ocean is killing the invasive species, so dead fish are now washing up on South Australian beaches.
Pictures from Middleton, Port Elliot and Goolwa show piles of juvenile carp littering the shores of the popular summer destinations.
The principal biosecurity officer for weeds and pests at the state’s Department of Primary Industries and Regions said it was normal for carp to spawn at this time of year, but that the high flows were flushing them from the fresh water of the River Murray into the marine environment.
“They’re normally tolerant [of different environments], but don’t take high salinity well ... that’s why we’re seeing fish deaths,” she said.
“Normally when there’s a fish kill event, the fish will be either consumed by other species or degrade and form part of the natural system,” she said. “We do still expect them to be washed back in over days and weeks.”
If the piles of rotting fish do accumulate, though, she said there is a plan to bring in contractors to remove them in a sustainable way, possibly through composting.
On Facebook, John Cork-Gorringe wrote there were mulloway and bream at Middleton as well.
“The shallows are alive with carp struggling in the salty water,” he wrote. “I will never see this again in my lifetime.”
Rodgers said the dead fish were mostly carp, which have invaded Australia’s rivers in enormous numbers.
In 2016, then-water minister Barnaby Joyce announced a plan to introduce the herpes virus into the carp population to control their numbers.
However, when the National Carp Control Plan was released at the end of the year, it recommended more research be done.
Carp have since been spawning in huge numbers, particularly after the floods.
A group of Charles Sturt University ecologists this week said the “videos of writhing masses of both adult and young fish illustrate that all is not well in our rivers.”
They described the “house of horrors” the carp cause as they degrade plants and habitats.
“They can make the bed of many rivers look like the surface of golf balls — denuded and dimpled, devoid of any habitat,” they said in the Conversation.
They said the previous estimate of up to 357 million fish in Australia’s rivers and wetlands could be exceeded this year.
“Carp are super-abundant right now, because floods give them access to floodplain habitats,” the ecologists said. “There, each large female can spawn millions of eggs and the young have high survival rates.”
It is a boom year because of the flooding and the spike in numbers has prompted calls for a release of the herpes virus.
When a hiker fell from a 55m waterfall in wild New Zealand bush, rescuers were forced to evacuate the badly hurt woman without her dog, which could not be found. After strangers raised thousands of dollars for a search, border collie Molly was flown to safety by a helicopter pilot who was determined to reunite the pet and the owner. A week earlier, an emergency rescue helicopter found the woman with bruises and lacerations after a fall at a rocky spot at the waterfall on the South Island’s West Coast. She was airlifted on March 24, but they were forced to
CONFIDENCE BOOSTER: ’After parkour ... you dare to do a lot of things that you think only young people can do,’ a 67-year-old parkour enthusiast said In a corner of suburban Singapore, Betty Boon vaults a guardrail, crawls underneath a slide, executes forward shoulder rolls and scales a steep slope, finishing the course to applause. “Good job,” the 69-year-old’s coach cheers. This is “geriatric parkour,” where about 20 retirees learned to tackle a series of relatively demanding exercises, building their agility and enjoying a sense of camaraderie. Boon, an upbeat grandmother, said learning parkour has aided her confidence and independence as she ages. “When you’re weak, you will be dependent on someone,” she said after sweating it out with her parkour classmates in suburban Toa Payoh,
HIGH HOPES: The power source is expected to have a future, as it is not dependent on the weather or light, and could be useful for places with large desalination facilities A Japanese water plant is harnessing the natural process of osmosis to generate renewable energy that could one day become a common power source. The possibility of generating power from osmosis — when water molecules pass from a less salty solution to a more salty one — has long been known. However, actually generating energy from that has proved more complicated, in part due the difficulty of designing the membrane through which the molecules pass. Engineers in Fukuoka, Japan, and their private partners think they might have cracked it, and have opened what is only the world’s second osmotic power plant. It generates
Chinese dissident artist Gao Zhen (高兟), famous for making provocative satirical sculptures of former Chinese leader Mao Zedong (毛澤東), was tried on Monday over accusations of “defaming national heroes and martyrs,” his wife and a rights group said. Gao, 69, who was detained in 2024 during a visit from the US, faces a maximum three-year prison sentence, said his wife, Zhao Yaliang (趙雅良), and Shane Yi, a researcher at the Chinese Human Rights Defenders group which operates outside the nation. The closed-door, one-day trial took place at Sanhe City People’s Court in Hebei Province neighboring the capital, Beijing, and ended without a