Communication is key in any relationship, including the ones we have with our pets. "Dogs make great efforts to communicate," says Carlo Siracusa, DVM, a clinical assistant professor of animal behavior at the University of Pennsylvania's School of Veterinary Medicine. And the tool that they use most with the people they know is body language. Understanding the basic components of those nonverbal cues — facial expressions, ear set, tail carriage, hair, and posture is the first step toward interpreting a dog's message. "But it's important that you look at the entire context," says Kristen Collins, senior director of ASPCA anticruelty behavior rehabilitation. Also keep in mind that many expressions have more than one meaning — like trembling, for one — and you'll need to consider the extenuating circumstances. "The secret is to put all these elements together to reach the best conclusion," says Siracusa. Here's how to interpret a canine conversation.
A content dog will move his tail slowly (or fast, if he's really happy to see you) in a kind of sloppy way. But if the tail is stiff, that can signal aggression, whether it's barely quivering or quickly whipping back and forth.
2. Raised Hackles
If the hair that runs along her spine stands up and she's also crouching, your dog may be afraid. But if she appears otherwise relaxed, that raised fur could just be a sign that she's itching to have fun, particularly if her eyes are focused and alert.
3. Eye Contact
Dogs usually avert their eyes when approaching other dogs to let them know they aren't a threat. A hard stare, however, often indicates they're ready to rumble, as do eyes that appear larger than normal. Some dogs, though, stare at other dogs when they want to play; in these cases, the dog is typically down on all fours in a pounce — ready position, or standing with a jaunty tail wag. A dog with squinty eyes may be anxious, especially when also hunched over. If you can see the whites of his eyes (sometimes called "whale eye"), that can mean he's guarding a favorite toy or resting spot, especially if his body is rigid — in which case it's best to let him be.
4. Lips Together (or Apart)
A dog that's in a good mood will usually have his mouth slightly open in a relaxed manner. If he's baring his teeth with the sides of the mouth pulled back tightly, stay away: This is the most recognizable sign of canine aggression. A dog that is anxious may lick his lips or yawn excessively, even when he's not feeling sleepy.
5. Stiff and Still
The classic "play bow" position, where the dog's front end is on the ground and his back end is up in the air, is the clearest invitation to play in a dog's vernacular. Beware of a dog whose body is coiled like a spring, however, with his weight shifted forward in a confident manner and his tail straight up over his back or quivering; he's most likely angry. A dog that is crouched over (often with his tail tucked under) and frozen still, as if trying to be invisible, may be feeling fearful or defensive.
6. Ears up or Back
If the ears are erect and pointing forward, it's one of two things: He's being frisky or combative, and you'll need to look to the tail (happy wag or stiff flagging?), eyes (staring or not?), and stance (play bow or not?) for other clues. If the ears are pulled back or flattened, this may be a sign of fear — especially when the dog's entire body seems to be tucked.
This can signal anxiety (I hear thunder!), but can also mean he's excited (I see a squirrel outside!) and ready to play. Of course, sometimes the answer is the easiest and most obvious one — that he's chilly and needs to warm up!
Dogs have a complex vocalization system that goes paw-in-paw with their body language. In general, high-pitched barks accompany excitement or need, while a lower pitch suggests aggression. When a dog "chuffs," with quick, breathy barks, he may be feeling anxious.