Scientists are investigating why baby southern right whales are washing up dead on Argentina’s Patagonian coast near Peninsula Valdes. Veterinarian Marcela Uhart, leading an investigation with a team of experts, suggests that infections caused by marine bacteria entering through wounds inflicted by kelp gulls may be responsible for the deaths. The affected area is around Puerto Madryn where residents have reported hundreds of carcasses; however, researchers are still determining the exact number and cause of death, with testing ongoing to identify specific bacterial strains involved in the calf fatalities.
Written locally by qwen2.5:14b on 2026-10-03,
using this article's own text rather than the other coverage of the
same event (that is the story summary below).
Story summary
In Argentina, specifically around Peninsula Valdes in Chubut province, scientists are investigating a mysterious surge in baby whale deaths. Scores of calf carcasses have washed ashore, with Marcela Uhart, a veterinarian from the One Health Institute at University of California, Davis, leading the investigation as head of the Southern Right Whale Health Monitoring Program. This area is a significant breeding ground for southern right whales, where they gather to give birth and nurse their young. Based on 23 years of monitoring data, Uhart confirms this event as unusual, suggesting that infections from marine bacteria might be causing fatal injuries in the calves.
Written for “Dead Baby Whales In Argentina” on 2026-10-05,
grounded in this article and the 2 other(s) covering the same event.
An investigation has been launched over the mystery of why baby whales are washing up dead on the coast of Argentina.
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whales → launch → Argentina
The country’s Patagonian coast has seen scores of the calf carcasses washing ashore around Peninsula Valdes, on the country’s Patagonian coast.
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scores → see → coast
Hunted to the brink of extinction in the 19th and 20th centuries, the whales now gather in the peninsula’s sheltered waters to give birth and nurse their young.
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whales → hunt → young
“We're looking into the whale calf deaths based on 23 years of monitoring that we have of this same population.
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we → look → population
That's what allows us to say that this is an unusual event," said Marcela Uhart, a veterinarian with the One Health Institute at the University of California, Davis, who is leading the investigation as head of the Southern Right Whale Health Monitoring Program.
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who → allow → Program
The leading hypothesis is that the whale calves are suffering infections from marine bacteria that can enter their bodies through injuries inflicted by kelp gulls, Uhart said.
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Uhart → lead → gulls
For decades, the seabirds have pecked at whales surfacing to breathe, gorging on their skin and blubber.
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seabirds → peck → skin
Adults learn to surface with only their heads exposed, keeping their backs underwater and out of reach of the gulls.
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heads → learn → gulls
Calves can't do that maneuver, leaving them vulnerable to attacks.
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Calves → do → attacks
The carcasses have been washing ashore around the gulf city of Puerto Madryn, including near the central waterfront where they alarm residents and tourists.
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they → wash → residents
Residents have reported hundreds of them, but researchers declined to give a death toll, saying that would become clear after the season ends around late November.
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season → report → November
Uhart and a team of biologists, veterinarians and park rangers have been searching the area for the dead calves from shore and with boats, planes and drones.
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Uhart → search → boats
The work is gruesome: They photograph and examine the bodies, racing against decomposition to collect skin and organ samples for testing at a veterinary school farther north, in the city of Tandil.
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They → photograph → Tandil
Bacteria have already been detected in those tissues, but researchers are still culturing samples to identify the microbes and determine whether infection was the cause of death, she said.
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she → detect → death
Even if bacteria are to blame, researchers must still determine why they have become so deadly this year.
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they → blame → ?
Changes in marine conditions like warming sea temperatures, potentially linked to climate change or El Nino, could contribute to “this perfect storm where this bacteria is powerful enough to overcome the immunity of the babies and cause their deaths,” Uhart said.
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Uhart → warm → deaths
“So to the extent that we can, we'll try to identify at least what factors may be triggering this event and making it so massive.”
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it → try → event
Right whales got their name from whalers who considered them the “right” animals to hunt because they swam slowly, stayed close to shore and floated when killed, according to the International Whaling Commission, a global body tasked with regulating whaling.
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they → get → whaling
Although illegal hunting continued into the 1970s, southern right whales have gradually rebounded since gaining international protection in 1935.
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whales → continue → 1935
But their recovery remains threatened by the same pressures facing whales worldwide: declining food supplies, fishing gear entanglements, oil spills and ship strikes.
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recovery → remain → whales
If losses on this scale recur, they could slow the population’s recovery.
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they → recur → recovery
By pinpointing what is killing the calves, researchers hope to find ways to protect the vulnerable population.
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researchers → pinpoint → population
“If the cause relates to something that we are doing as humans, then we need to change that,” Uhart said.
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Uhart → relate → that
“We don’t want to endanger these whales again.”
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We → want → whales
The Aporia
