A bacterial infection is suspected of causing the deaths of hundreds of baby southern right whales along the coast of Argentina, according to a marine mammal expert who spoke with AFP on Thursday. This week, dozens of whale calves were found dead on beaches in southern Chubut province, continuing a worrying trend that began in June. Mariano Coscarella, a researcher at the Marine Mammals Laboratory of Argentina’s national research council, Conicet, said the death rate among young whales this season is unusually high. Coscarella, based in Puerto Madryn—a popular whale-watching spot on the Atlantic coast—explained that veterinarians suspect an outbreak of erysipelas, a serious disease caused by bacteria typically found on the skin of marine mammals. Erysipelas can lead to severe skin infections and, in some cases, systemic illness. While the condition is known to affect a range of animals, including livestock and marine mammals, its impact on whale populations is less commonly documented. Coscarella noted that while the cause appears to be natural, human activity cannot be entirely ruled out. The Chubut provincial government has confirmed it is working closely with scientists to investigate the cause of the deaths. Preliminary findings suggest a common marine bacteria may be responsible, though further research is needed to confirm this. Puerto Madryn and the nearby Valdes Peninsula are key breeding grounds for southern right whales, which can grow up to 17 meters (55 feet) long and weigh around 40 tons (36,000 kilograms)—roughly the same as four elephants. In 2025, a record 2,110 whales were counted in the area, including 800 young. This year, authorities have counted 1,375 whales, including nearly 400 calves, according to Coscarella. While the recent deaths are concerning, he emphasized that they do not pose a medium-term threat to the overall whale population. Southern right whales are estimated to live up to 60 years, meaning the current losses, while significant, are not expected to drastically alter the population over time. Scientists continue to monitor the situation closely and are collecting data to better understand the cause of the deaths and any potential environmental or health factors involved. The collaboration between local authorities and researchers is crucial in determining whether the issue is isolated or part of a larger trend that could affect the region’s marine ecosystem.