The Mystery of Japan’s Water Bottles Along Streets and Fences

If you’ve ever walked through quiet residential streets in Japan, you may have noticed clear plastic water bottles lined up near fences, garden edges, or walls. While they may seem like forgotten trash or leftovers from a picnic, these bottles are placed intentionally — as cat deterrents known as nekoyoke.

Despite Japan’s affection for cats, stray cats pose concerns such as property damage and disease transmission. In response, some residents place water bottles outside to discourage stray cats from entering their spaces or using them as litter areas.

The practice may seem strange to outsiders, but it’s common across Japanese cities. The belief is that sunlight or streetlights reflecting through the water causes flashes that startle cats. Others say distorted reflections or disrupted depth perception may also confuse felines.

Interestingly, this habit didn’t originate in Japan. It’s believed to have started in the West in the 1980s as a way to deter dogs. Japan adapted the idea, modifying it to protect gardens and walkways from cats instead of canines.

But does it actually work?

Animal behavior experts say no. There’s no scientific proof that water bottles reliably repel cats, especially in low-light conditions. Nonetheless, many continue the practice—part habit, part hope.

Though not proven effective, the bottles are harmless. Over time, nekoyoke has become less of a pest control method and more of a cultural curiosity. It reflects the Japanese values of creativity, cleanliness, and subtle problem-solving.

So while the effectiveness remains debatable, the tradition adds charm and mystery to Japan’s neighborhoods—and makes for an unforgettable detail for those visiting or watching from afar.