Unusual ocean conditions linked to a developing El Niño have led to a series of notable occurrences along California’s coastline, including the recent discovery of a hazardous Marine Corps marker on a Ventura County beach.

Last week, a Navy MK25 phosphorus location marker, designed to emit smoke and flame signals in water rescue scenarios, washed ashore. The precise location of the find was not immediately disclosed by authorities, and the Ventura County sheriff’s office did not respond to early inquiries. According to an Instagram post by the county’s bomb squad, a local resident found the marker at the waterline, took it home out of concern for public safety, and contacted law enforcement. Bomb disposal teams from the Ventura County sheriff’s office and Naval Explosive Ordnance Disposal at Point Mugu responded to the residence in Ojai to secure the device.

Officials cautioned that although the resident acted with good intentions, marine markers remain highly dangerous. Even if spent and waterlogged, residual phosphorus within can dry and spontaneously ignite or explode when handled. Temperatures generated by such markers can reach up to 3,000 degrees Fahrenheit, and the chemical agents involved are toxic.

This incident is not isolated. In July, a potentially more hazardous piece of military ordnance—a live Super Bazooka round dating back to the 1950s—was found at Mugu State Beach, near Point Mugu State Park along the Pacific Coast Highway. The area, once a military training ground before becoming a public beach, reveals buried ordnance as erosion removes layers of sand. Due to the round’s unstable condition, authorities temporarily closed the beach and roadway to dispose of it safely on site.

Officials have urged the public to avoid touching or moving any suspected military devices encountered on beaches and to immediately evacuate the vicinity and call emergency services.

The intensified storm activity and warmer ocean temperatures associated with the El Niño phenomenon have contributed to notable environmental changes along the Southern California coast. Sand erosion has exposed long-buried structures such as jetties near Newport Harbor, originally constructed to protect shoreline properties.

Marine life typically uncommon in these waters has also been observed. Near Malibu Pier, a hammerhead shark was spotted, despite generally favoring warmer ocean environments. Remarkably, in early September, two olive ridley sea turtles—species native primarily to tropical Pacific, Indian, and Atlantic regions—were seen nesting on Seal Beach and Huntington Beach, marking historic firsts for the area. These turtles usually nest in countries like Mexico, Nicaragua, Costa Rica, and Panama.

The series of unusual findings underscores the dynamic changes underway along California’s coastlines amid evolving oceanic and meteorological conditions. Authorities continue to monitor these developments while emphasizing public safety in relation to exposed military ordnance and shifting marine habitats.