A 9-foot great white appears off San Diego beach, and warm waters could bring more

Authorities posted caution signs at La Jolla Shores on Tuesday evening after a 9-foot great white shark was spotted near one of San Diego's most popular beaches, as NBC San Diego reported.

Officials told the station the shark was not behaving aggressively, but the sighting comes as experts warn that unusually warm Pacific waters may bring more great whites into Southern California this summer.

What happened?

According to NBC San Diego, the shark was seen near La Jolla Shores at about 7:15 p.m. The San Diego Fire-Rescue Department said it was outside the surf line, and advisory signs were posted along the beach, per the outlet.

Candace Hadley of the San Diego Fire-Rescue Department said the signs were put up "out of an abundance of caution" in remarks to NBC San Diego.

Because juvenile great whites are generally 6 to 10 feet long, the 9-foot shark was likely a juvenile. Earlier this year, CSU Long Beach Shark Lab director Chris Lowe told NBC San Diego that researchers were seeing more baby white sharks born in February, even though that usually happens in April.

Lowe told the station that change was tied to warm-water conditions that have continued since December. According to the CSULB Shark Lab, adult great whites can grow to 20 feet and live for more than 70 years.

Why does it matter?

A shark sighting at a busy destination like La Jolla Shores can lead to public safety decisions and disrupt local recreation.

If marine heat waves continue, local waters in Southern California could see more great whites.

Scientists have long documented that marine animals respond to changes in water temperature, prey availability, and habitat. 

As human-caused pollution warms the planet and raises ocean temperatures overall, it can affect where wildlife gathers and when seasonal patterns occur, increasing the chances of encounters between people and animals that are simply following shifting conditions.

A shark sighting doesn't automatically mean the risk of an attack is high. Great whites are part of the coastal ecosystem, and officials emphasized that this shark was not behaving aggressively.

What's being done?

The advisory signs provide the public with some easy awareness that sharks are in the water. Lifeguards are in the area and will be on the lookout for any new shark activity, as NBC San Diego noted.

Lowe downplayed the immediate concern to beachgoers to the outlet, pointing out that sharks typically stay away from people and are commonly unnoticed in the water.

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