SOUTHERN CALIFORNIA — Unusually warm ocean temperatures along the Southern California coast are pushing shark activity closer to shore this summer, according to researchers who have been monitoring local waters. Drones have spotted sharks near beachgoers on 97% of survey days in the region.

"The water has been progressively warmer — unusually warm," said Chris Lowe, director of the Shark Lab at California State University, Long Beach. "We think that may have brought females back earlier to give birth. All those are signs it will be a sharky summer," he said.

The warmer conditions, combined with a potential El Niño, could recreate circumstances seen a decade ago when sharks moved closer to shore. Water temperatures currently off Southern California fall within sharks' preferred range.

Recent encounters have already put beachgoers on alert. Ocean access in Newport Beach was temporarily halted after a surfer spotted a shark gliding beneath her and circling just below her board. In Hermosa Beach, a fisherman hooked a young great white shark and attempted to guide it safely back into the water.

Tracking data shows sharks have been especially active across Santa Monica Bay and toward Santa Barbara. Beaches such as Long Beach and Huntington Beach could also see increased shark sightings this summer.

Juvenile sharks, which typically measure 5 to 6 feet in length, prefer shallow, sandy waters where they can avoid predators and feed on stingrays and smaller sharks near shore. Drone footage shows the animals often swimming just beneath beachgoers, largely ignoring them.

"People and juvenile sharks appear to coexist. Humans aren't seen as prey," he said.

Shark bites in California average fewer than two per year statewide, according to the California Department of Fish and Wildlife. Researchers at the Shark Lab continue to monitor local waters for shark activity.