Bearded Dragons are wonderful pets, and because of this many first time beardie owners end up with more than one dragon. In addition, pet stores will tell potential new owners that if they purchase more than one dragon they can live in the same enclosure together, which seems like a great idea. That is, until you come home to an injured dragon who may be missing a toe, part of their tail, or even a whole foot!
There are countless stories of beardies being injured from being housed together. They are not social animals, and this statement applies to all beardies, whether male or female. There is a common misconception that female Bearded Dragons will not become dominant or aggressive, or that males will not be aggressive with females. This is NOT the case. All dragons have the potential to be aggressive and even if no outright aggression is observed, there are many subtle behaviors that Bearded Dragons display which, on the surface, look like friendly behaviors, but are in fact signs of dominance or submission, leading to bigger problems. Beardies housed together may compete for food, territory, and even the basking spot. This can lead to malnutrition and health problems in the submissive beardie.
While housing dragons of any sex together is not recommended, housing a male and female together creates the additional complication of them breeding, which they will do. In general, when breeding Bearded Dragons, the male and female are placed in a controlled environment together for copulation to take place, and then separated back into their own enclosures. A female beardie can become stressed when housed with a male, even if she has mated with him in the past, and stress can lead to all sorts of problems such as loss of appetite, egg binding, and even death.
Dominant behaviors have been observed in dragons as young as 3-5 months old. While young dragons are often housed together at this age, as soon as dominant behaviors are observed, they should be separated. Pet stores will often house young beardies together, making it appear as though this practice can continue in your home. While there are isolated examples of this working out, it usually results in injury (or death) to one or both dragons.
Some common behaviors which are often observed include 'waving', where a beardie will wave their arm at another dragon. This is a submissive behavior and often the first sign of trouble. Dominant behaviors include sitting on top of one another (though this may look cute and is often mistaken for 'snuggling', it is actually a show of dominance to stand or lay on top of the other dragon). Humans misinterpret these as friendly, playful behaviors and injury or death is often the result. People will often say to me that they've never seen their dragons be aggressive with one another, and I ask them how often they are able to sit and closely observe their behavior all day long. The answer, as you might expect, is 'never', which means we really don't know what goes on when we aren't around. The bottom line is, if you purchase more than one dragon, be prepared to purchase an additional enclosure, lights, UVB source and cage furnishings. Do not put your animals at risk on the assumption that your situation will be one of the few that works out.