Blue whales are not considered dangerous to humans in a typical sense. The real risk comes from their huge size and from boats getting too close, not from aggression.
General behavior
Blue whales are gentle filter feeders that eat tiny animals like krill using baleen plates instead of teeth, so they do not hunt large prey or people. They are described as non‑aggressive and usually avoid close contact with humans and vessels when they can.
Known risks to people
The main danger is accidental: a slap from the tail, a sudden change of direction, or a breach near a small boat could cause serious injury or damage simply because of their enormous mass. There are no documented cases of blue whales deliberately attacking and killing humans; incidents involve collisions or vessels being struck, not predatory behavior.
Safety and conservation
Experts advise never trying to swim close to or touch blue whales because even curious or defensive movements can unintentionally harm a person. Blue whales themselves are endangered and are far more threatened by humans—through ship strikes, noise, and past whaling—than humans are threatened by them.
