For the first time, a study has shown how juvenile great white sharks respond to hazardous weather conditions after a nursery was partially abandoned by the animals during Tropical Storm Hilary in 2023.

And believe it or not, this study matters for humans, too.

A team from the Semmens Lab at UC San Diego Scripps Institution of Oceanography equipped 22 juvenile white sharks with acoustic transmitters, allowing them to track their behavior before, during and after the arrival of Tropical Storm Hilary, which peaked as a Category 4 hurricane the day before it began to impact Southern California as a tropical storm.

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(WATCH: The water’s warmer and the sharks are getting closer)

Before the storm, the team was consistently getting pings from 16 to 19 sharks in the nursery each hour. During the storm, that number fell by roughly half, to as few as eight sharks per hour.

If that wasn’t interesting enough, the authors went into this study thinking the sharks would swim to deeper areas farther offshore, where they could lay low, so to speak, until the storm had passed. 

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While one shark did ping at a depth of 433 feet during the storm, potentially to do just that, the data actually suggests something different for many of the sharks.

There was an increase in juvenile white shark reports before and during the storm in La Jolla Cove, a more sheltered area that can act as a storm shelter for juvenile great white sharks, in a way.

(MORE: Beyond the weather, what does El Niño mean for marine life?)

The shark version of a tropical storm warning

It wasn’t necessarily the waves that drove the sharks out of their usual habitat. The study found that the falling sea surface temperatures during the storm were the most influential predictor of the sharks hitting the road.

The water temperature fell from 68 degrees to 57 in less than 24 hours in the nursery, and because juvenile white sharks are more sensitive to rapid temperature changes, it makes sense that they would choose to search for warmer waters.

While a past study showed juvenile white sharks leaving their habitat for a whole season when a strong upwelling event cooled the water for a longer period of time, the water in the case of Tropical Storm Hilary cooled for only a matter of hours.

Most of the sharks were back within days after Hilary passed, and nearly all were back within three weeks.

Just like people, they came home after the danger had passed.

What it all boils down to

These are not normal conditions for the nursery habitat. It is located just off the west coast of California near San Diego, and it’s not an area prone to hurricanes or tropical activity. In fact, August 2023 is the only time the San Diego National Weather Service office has ever issued tropical storm warnings.

By understanding how juvenile white sharks respond to temporary changes in their environment, we can better predict their behavior in the future, especially as global climate change influences local weather patterns.

If we can predict how sharks will respond to certain weather conditions, we can do a better job protecting them and potentially minimizing the opportunities for humans and sharks to meet unexpectedly in the wild.

Sara Tonks is a content meteorologist with weather.com and has a bachelor’s and a master’s degree from Georgia Tech in Earth and Atmospheric Sciences, along with a master’s degree from Unity Environmental University in Marine Science.