US Politics

Investigators in Argentina are working to understand why an unusually high number of baby whales are washing ashore dead along the country's Patagonian coast. Scores of calf carcasses have been found near Peninsula Valdes, a key breeding area for southern right whales.

Marcela Uhart, a veterinarian with the One Health Institute at the University of California, Davis, and head of the Southern Right Whale Health Monitoring Program, stated that based on 23 years of monitoring, the current situation is unusual. The leading hypothesis among researchers is that the whale calves are succumbing to infections from marine bacteria. These bacteria may enter their bodies through injuries inflicted by kelp gulls.

Kelp gulls have a history of pecking at surfacing whales for skin and blubber. While adult southern right whales have learned to surface with only their heads exposed to avoid the birds, calves are more vulnerable to these attacks due to their inability to perform this maneuver. The carcasses have been reported near Puerto Madryn, a coastal city known for its tourism.

Uhart and her team, comprised of biologists, veterinarians, and park rangers, are collecting samples from the deceased calves for testing. The team is conducting surveys from land, boats, planes, and drones. Initial tests have detected bacteria in tissue samples, but further culturing is underway to identify the specific microbes and confirm if they are the cause of death.

Researchers are also examining environmental factors that could be contributing to the increased mortality. Scientists are probing if warming sea temperatures, potentially linked to climate change or El Nino, could be making the bacteria more virulent. Uhart noted that understanding these triggering factors is crucial, especially if human activities are involved.

Southern right whales were once hunted to near extinction but have seen a gradual recovery since gaining international protection in 1935. However, their population remains vulnerable to threats such as dwindling food supplies, entanglement in fishing gear, oil spills, and ship strikes. The current high calf mortality rate could impede the population's recovery if similar events occur in the future. The research aims to identify the causes of these deaths to implement protective measures for the whale population.