Stranger danger

How it works

The phrase is borrowed from child-safety language and has no technical meaning. What it usually describes ranges from mild to intense: a dog who hides behind their owner, barks from across the room, backs away when a visitor reaches toward them, or growls and lunges at people on walks. Some dogs are worried by most strangers, and others only by particular features such as hats, beards, a certain height or a certain way of moving. Veterinary behaviorists report fear as the most common driver of aggression toward unfamiliar people, with gaps in early social experience among the most prominent contributing factors, alongside genetics and frightening experiences.

What it looks like

A dog greets family members happily at the door. When a delivery driver in a cap and a bright vest steps onto the porch, the dog backs down the hallway, barking with their weight shifted back, and only creeps forward to sniff the doormat once the driver has left.

Commonly confused with

Aloof behavior

Aloof behavior is calm indifference to unfamiliar people, with a loose body and no sign of fear. Stranger danger describes a dog who is worried by them, which shows up as avoidance, stress signals or a defensive display.

Related terms

Sources

• Haug (2009), Canine aggression toward unfamiliar people and dogs, dvm360 proceedings