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It was supposed to be the perfect beach day.
The sun was shining, the waves were gentle, and families lined the shoreline with colorful umbrellas and coolers. Children laughed as they built sandcastles, surfers waited patiently beyond the breaking waves, and the smell of sunscreen filled the warm ocean breeze.
My family had only been at the beach for about an hour when something unusual caught my attention.
One of the lifeguards climbed onto the observation stand and replaced the usual warning flag with a bright purple flag.
Within moments, another lifeguard began walking along the shoreline, blowing a whistle and calling everyone out of the water.
“Everyone out, please! Exit the water immediately!”
People looked around in confusion.
There were no large waves.
The weather was beautiful.
There wasn’t a storm cloud in sight.
I assumed someone had spotted a shark.
Instead, I noticed that the lifeguards looked calm—not panicked. They were simply making sure everyone left the water quickly but safely.
Curious, I walked over to one of them.
“Excuse me,” I asked. “What’s happening?”
He pointed toward the purple flag fluttering above the lifeguard station.
“We’ve raised a purple flag.”
I stared at him.
“I’ve never seen one before.”
He smiled.
“Most people haven’t.”
Then he explained something that completely changed the way I look at beach safety.
Unlike the familiar red or yellow warning flags that indicate surf conditions, a purple flag is commonly used at many beaches to warn visitors about dangerous marine life in the water.
That doesn’t necessarily mean sharks.
In fact, sharks are usually indicated by different local warning procedures depending on the beach.
A purple flag often signals the presence of creatures such as:
- Jellyfish
- Portuguese man o’ war
- Stingrays
- Sea lice
- Other potentially dangerous marine animals
Just as he finished explaining, another lifeguard pointed toward the shallow water.
At first, I couldn’t see anything.
Then sunlight reflected off dozens of tiny translucent shapes drifting with the current.
Jellyfish.
Hundreds of them.
Some were no larger than a coin.