A Walk on the Peak
Night falls quickly on Hong Kong Island. Street lamps hum to life, and the tall buildings begin to sparkle with electric light. But if you walk away from the concrete and head up into the hills, a different kind of glow appears in the dark.
On the Pok Fu Lam Family Walk, people sometimes spot a small beetle named Pygoluciola qingyu. This insect makes its own light right here in the park. It does not use batteries or plugs. It uses chemicals inside its body to create a soft, greenish-yellow flash.
Visiting a place where fireflies live takes patience. You cannot rush through the trees with a bright flashlight. If you turn on a phone screen or a loud torch, the fireflies stop flashing. They get confused by the sudden brightness.
Instead, visitors stand quietly near the bushes and wait for their eyes to adjust to the dark. After a few minutes, the shapes of the leaves emerge. Then, a tiny spark blinks on near the ground.
What Makes These Beetles Special
Every firefly species has its own way of communicating. The fireflies you find on the Pok Fu Lam Family Walk are different from the ones you might see in a backyard in North Carolina or a meadow in Germany. They use specific patterns of light to talk to each other.
When scientists and citizen scientists record these insects, they pay close attention to the details. They look at the color of the flash. They measure the time between blinks. They note the exact date and location.
On September 5, 2026, observers logged Pygoluciola qingyu right here on Hong Kong Island. These records help researchers understand where the beetles are living and how many of them are still around.
Watching fireflies in a busy city like Hong Kong reminds us of how much nature exists right next to our neighborhoods. You do not need to travel to a deep, untouched jungle to find wild animals. Sometimes, you just need to walk up a familiar trail, turn off your phone, and look closely at the grass.
Protecting the Night
Cities grow larger every year. More buildings go up. More streetlights shine into the trees. This extra light makes it hard for fireflies to see each other's signals.
If a male firefly cannot see a female's response, he cannot find a mate. When cities get too bright, firefly populations start to drop.
People who visit firefly spots help protect them by keeping the area dark. They use red filters on their flashlights if they need to see the path. Red light does not disturb the insects as much as white light does.
Citizen science projects rely on people visiting these spots and writing down what they see. When you log a sighting, you add a small piece of data to a very large map. Scientists use that map to track changes over time.
Next time you take an evening walk in a park, look toward the damp soil near the ferns. You might see a flash of light that tells you a tiny beetle is right there beside you.