Breaking Update: Here’s a clear explanation of the latest developments related to Breaking News:Officials Confirm Small Bird Flu ‘Outbreak’ in Elephant Seals at Año Nuevo State Park– What Just Happened and why it matters right now.
At the park, public elephant seal tours have been canceled for the remainder of the season. California State Parks said the decision was made “out of an abundance of caution” to protect both wildlife and to avoid inadvertently spreading the virus through foot traffic in affected areas.
Año Nuevo State Park hosts one of the most intensively studied elephant seal colonies in the world, led by researchers at UC Santa Cruz. About 3,000 seals use the mainland site during the winter breeding season, and scientists have tracked more than 55,000 individuals over six decades through flipper tags and long-term monitoring.
“That long-term individual-based data set gives us a really unparalleled opportunity to understand how this virus affects uniquely identifiable animals,” said Roxanne Beltran, who leads the program at UC Santa Cruz.
So far, the outbreak appears concentrated among weaned pups — young seals that have recently been left behind after their mothers return to sea. Two weeks ago, researchers counted roughly 930 pups and weanlings on the beach. Beltran said about 95% of adult females had already departed on their foraging migrations when the outbreak began, a detail scientists hope may limit broader impact.
“Avian influenza has affected only a small proportion of the weaned pups at this time,” Beltran said. “There are still thousands, apparently healthy animals in this population.”
Still, researchers are bracing for uncertainty. In South America in 2023, H5N1 devastated southern elephant seals in Argentina, with major pup losses that altered the population’s trajectory.
“A change in the number of pups that survive in a given year has a really, really long-lasting consequence,” Beltran said. Northern elephant seals can live more than 20 years, and population shifts ripple across decades.
Scientists do not yet know how the virus is spreading at Año Nuevo — whether through direct contact with infected birds, environmental exposure such as feces, or seal-to-seal transmission. Genetic sequencing of the virus is underway and could take weeks to clarify whether it matches the dominant bird strain circulating now.
Meanwhile, monitoring has intensified. Teams are conducting systematic beach surveys, collecting samples from sick animals, flying drones to assess colony-wide health and coordinating across agencies, including NOAA Fisheries and The Marine Mammal Center.
At The Marine Mammal Center in Marin County, responders have temporarily paused hands-on responses for elephant and harbor seals while assessing risks.
“My biggest concern is that this perpetuates and continues to spread and paralyzes the operations,” said Dominic Travis, the center’s chief executive. “We’re going to be assessing that day by day.”