Red Dragonflies Are Back From Their Mountain Getaway! The Hidden Travel Secret of the Akiakane
I’m Science Trainer Ken Kuwako. Every day is an experiment.
The Amazing Journey Hidden Behind the Bright Red Dragonfly
On crisp autumn days, you’ve probably spotted a brilliant red dragonfly gliding over rice fields or parks. The sight often brings back warm childhood memories. But did you know that during the hottest months of summer, these tiny insects are nowhere to be found because they’re living high up in the mountains? Today, let’s take a closer look at one of Japan’s most familiar autumn insects, the Akiakane dragonfly, through a series of photos and some fascinating science.
I recently came across an Akiakane and couldn’t resist taking a few photos. In Japan, people often call it an “aka-tonbo” (red dragonfly), but that isn’t actually the name of a single species. Instead, it’s a general term used for several dragonflies that turn red. The ones we most commonly see are usually the Akiakane or its close relative, the Natsuakane.
They Actually Spend Their Summers at a Mountain Resort!
Although the Akiakane is famous as a symbol of autumn, its yearly life cycle involves an incredible migration. Around June, after emerging from rice paddies, these dragonflies leave the lowlands before the summer heat arrives and head for cooler mountain regions. They spend the hottest months on high plateaus, often more than 1,000 meters (3,300 feet) above sea level, where temperatures are much more comfortable.
As autumn arrives and temperatures begin to fall, they make the journey back down to the plains. That’s exactly when we start noticing red dragonflies flying around our neighborhoods. In a way, they’re like tiny migratory birds, making remarkable seasonal journeys every year.
Even their bright red color has a story to tell. When they first emerge as adults, their bodies are actually yellowish. During their stay in the cool mountains, the dropping temperatures gradually trigger the vivid red coloration we associate with autumn. Just like leaves changing color, these dragonflies transform with the seasons—a wonderfully poetic part of nature.
What Does the World Look Like Through 50,000 Eyes?
A dragonfly’s eyes are known as compound eyes. Each compound eye is made up of thousands of tiny individual units called ommatidia. Altogether, a dragonfly has around 50,000 of these miniature eyes.
Each ommatidium mainly detects light and darkness rather than producing a detailed image. If we compare this to a digital camera, a dragonfly’s vision is roughly equivalent to a camera with about 50,000 pixels. Modern smartphones easily exceed 10 million pixels, so the dragonfly’s view of the world is probably much less detailed—more like a coarse mosaic than the crisp images we see.
But what dragonflies lose in image quality, they more than make up for in performance. Their compound eyes provide an incredibly wide field of view and are exceptionally good at detecting movement. Instead of focusing on sharp detail, their vision is optimized to catch even the slightest motion. That’s why dragonflies can snatch tiny flying insects out of the air with astonishing precision. It’s a wonderful example of how evolution shapes living things for exactly the jobs they need to do.
Once you know these stories, a simple red dragonfly drifting through the autumn sky becomes much more than a familiar insect. It carries memories of cool mountain summers, dramatic seasonal color changes, and a remarkable set of 50,000 tiny eyes. Nature is full of hidden wonders, even in the creatures we pass by every day. The next time you see a red dragonfly, take a moment to imagine the incredible journey it has already made.
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