Popular Bay Area park where tens of thousands of seals gather closed to public after animals mysteriously die

A beloved Bay Area wildlife attraction abruptly canceled more than 600 seal tour reservations this week after California park officials discovered multiple sick and dead animals.

Año Nuevo State Park in San Mateo County, known for its winter gatherings of elephant seals during their pupping season, paused hundreds of tours while researchers investigate the cause of the illnesses and deaths. Multiple agencies are involved and have collected samples to test for avian influenza, with results still pending.

A “small number” of adult elephant seals, weaned pups and seabirds have been affected, according to Adeline Yee, a spokesperson for California State Parks told The Independent.

“Most seals on the beach appear healthy. Out of an abundance of caution, access is being paused to give wildlife space and allow for ongoing monitoring. Thank you for your understanding,” the Año Nuevo State Park website reads.

Tours are canceled through March 1. To date, 134 tours and 617 reservations, totaling 1,203 tickets, have been affected, including 22 schools, Yee told The Independent. Tickets, which cost $11 each, include a three-to-four-mile guided hike to view and photograph the massive two-ton animals.

Elephant seals along the California coast have their pupping season from December through March, with most pups being born in late December and January. During this time, female seals come ashore to give birth and nurse their pups for about three-to-four weeks.

Male elephant seals arrive earlier to establish breeding territories, which overlaps with the pupping period. Once the nursing period ends, the pups are weaned and must start fending for themselves, usually by late January or early February, though some pups born later may stay into March.

Biologists and wildlife experts from multiple agencies, including the University of California campuses at Santa Cruz and Davis, the California Department of Fish and Wildlife and federal partners, are working to determine what caused the illness and fatalities.

Despite the suspension of guided tours, certain areas of Año Nuevo State Park remain open to the public. Visitors can still access the Marine Education Center, the Horse Barn Movie Theater and a portion of the Año Nuevo Point Trail, though viewing of the seal colony itself is restricted for now.

Full tour refunds are available through the Reserve California website or by calling 800-444-4445.

The park’s elephant seals have rebounded dramatically from near‑extinction in the late 19th century, when they were heavily hunted for their blubber, which was used to make oil. Today, populations across California is nearly 200,000, making the annual winter pupping season a must-see among tourists.