How should I manage same-sex aggression between Great Danes?

While Great Danes are generally known as “gentle giants,” same-sex aggression (SSA) can certainly occur, particularly between two females or if you adopt littermates. This interdog aggression often becomes apparent as the dogs reach social maturity, typically between 18 and 36 months of age.

Because of their massive size and strength, managing tension between Great Danes requires strict environmental control and behavioral strategies:

Strict Supervision and Separation

• Separate when unsupervised: Never leave same-sex dogs alone together if they are experiencing tension. Use separate crates, baby gates, or securely closed doors in different rooms when you are not there to actively monitor them.

• Crate and Rotate: If the dogs are highly incompatible, you can use a “crate and rotate” routine. This involves keeping one dog securely crated or kenneled while the other enjoys free time with the family, alternating their turns.

• Use tethers: If you want both dogs in the same room but fear an altercation, you can tether them to opposite ends of the room so they can safely relax on the floor or couch without being able to physically reach each other.

Resource Management

• Feed separately: Always feed the dogs at the same time, but keep their bowls several feet apart—or feed them in their respective crates—to prevent food-related competition.

• Supervise high-value items: You must highly supervise the dogs around high-value items like fresh, meaty bones. Even normally friendly Danes can instantly break into a severe fight if one tries to steal the other’s prized bone.

Training and Reinforcement Strategies

• Reward the appropriate dog: Disregard outdated advice about supporting a “dominant” or “alpha” dog. Instead, identify which dog is behaving the most politely and calmly for the situation, and reinforce that dog by feeding them first, letting them out the door first, or petting them first.

• Avoid physical punishment: Never physically punish your dogs, yell, or scream if they show aggression. Great Danes are a sensitive breed, and punishment only adds to the tension, raises their distress, and may cause them to fight harder or redirect their aggression toward you.

• Practice obedience cues: Build a solid foundation of positive reinforcement training, practicing commands like the “watch me” cue to easily redirect their attention if a situation starts to heat up.

Safety Tools and Body Language Monitoring

• Bell the aggressor: Attach a distinct-sounding bear bell to the aggressive dog. This allows you to track their movements throughout the house and serves as an auditory warning to the victim dog that the aggressor is approaching.

• Use head collars: If the dogs are tense, have them wear head collars (like a Gentle Leader) indoors or on walks. This tool allows you to easily close an aggressive dog’s mouth and turn their head away if they begin to stare or fixate on the other dog.

• Watch for “Puppy Passes”: If one Dane is younger, do not allow them a “puppy pass” where they are permitted to lay their head, paws, or entire body over the older dog’s back, as this is a warning sign of an escalating status challenge.

• Be vigilant in tight spaces: Pay close attention to narrow areas like hallways, doorways, or staircases, as these are common locations where dogs will try to block or control each other.

Safe Intervention: If a fight does break out between your Danes, never put your hands or body between them or grab their collars, as excited dogs can easily mistake you for the other dog and inflict severe bites. Instead, use “remote control” tactics to break up the fight, such as throwing a heavy blanket over them, wedging a broom or cardboard between them, or spraying them with a water hose or a bottle of club soda.