science & environment•Fri, July 31, 2026•5 min read

The First Thing a Shark Notices About You Isn't What You Think

Forget the 'Jaws' mythology—new research suggests sharks are more tuned into your acoustic signature than your scent. A groundbreaking study from the CSULB Shark Lab reveals just how easily sharks can track human movement in the water.

It’s Not About the Smell

For decades, pop culture has ingrained the idea that sharks are blood-thirsty predators tracking human scent across miles of ocean. However, recent scientific findings are turning that narrative on its head. A first-of-its-kind study from the CSULB Shark Lab suggests that before a shark ever catches a whiff of anything, it is likely listening to the unique sounds we create while swimming, kayaking, or paddling.

The Acoustic Signature of Human Activity

Researchers at the Shark Lab developed a unique hearing test to see how sharks perceive human activity. Using high-tech multichannel hydrophones, they recorded the sounds of humans performing common ocean activities: freestyle swimming, kayaking, and surfing. They then played these audio clips back underwater at varying distances to monitor how sharks reacted.

Juvenile great white sharks can detect human activity from as far as 100 feet away.
The sound, rather than blood or bait, is often the first cue that draws a shark's interest.
The study recorded 3D movement of sounds to replicate how human motion translates underwater.

Staying Safe in Shark Territory

While the news that sharks hear us coming from 100 feet away might sound alarming, experts emphasize that awareness is the best form of safety. The CSULB Shark Lab maintains a dedicated California Shark Beach Safety Program aimed at educating the public on how to share the ocean with wildlife. Additionally, personal deterrents, such as magnetic devices like Sharkbanz, have shown anecdotal success in the field, helping surfers and divers feel more confident in deep water.

You don’t have to let fear rule your love for the ocean. We can be aware, prepared, and still wildly free.
— Bethany Hamilton

Key Takeaways

Sharks primarily detect humans through sound, not just scent.
Great white sharks can hear human swimming and paddling from 100 feet away.
Sound is often the first trigger that causes a shark to investigate human activity.
The CSULB Shark Lab is a primary resource for ongoing research into beach safety and human-shark coexistence.
Understanding shark behavior is more effective for safety than relying on myths or fear.

FAQ

Can sharks hear me swimming?

Yes. Research from the CSULB Shark Lab shows that juvenile great white sharks can detect the sounds of freestyle swimming, kayaking, and surfing from up to 100 feet away.

Is smell the primary way sharks find humans?

While smell is a powerful sense for sharks, this new study suggests that the acoustic signature—the specific noise we make—is often the first thing they notice.

Are there tools to help stay safe while surfing?

Yes, devices like magnetic shark deterrents (e.g., Sharkbanz) are used by water sports enthusiasts to provide peace of mind in the ocean.

Where can I find reliable shark safety information?

The CSULB Shark Lab offers extensive resources, including their California Shark Beach Safety Program, which provides evidence-based safety tips.