The “cucumber prank” is a viral internet trend where someone quietly places a cucumber behind a cat while it’s eating or distracted. When the cat turns around and suddenly notices it, it often jumps or reacts dramatically—like it’s startled by a snake.

Why cats react that way
Cats have a strong instinct to avoid snakes (a natural predator in the wild).
The surprise element (something appearing suddenly behind them) triggers a fear response.
It’s not really about the cucumber itself—it’s about unexpected change in their environment.
Is it safe?

Not really. While it can look funny, experts generally discourage it:

It can cause stress or anxiety for the cat.
The sudden scare might lead to injury (jumping into furniture, etc.).
Repeated pranks can harm your cat’s trust in you.
Bottom line

It’s one of those internet trends that seems harmless but isn’t great for the animal. If you want to entertain your cat, interactive toys or playtime are a much better (and kinder) option.