If you speak to emergency services personnel, many are quick to agree that when the moon is full, they're kept unusually busy with strange incidents and people behaving in odd ways. Indeed, the term "lunatic" is derived from the Latin word "luna", which means "moon." There are a few theories about this. One is that the moon influences the movement of the tides, and because our bodies consist of a lot of water, it's having a similar effect on us. Another suggestion is that there are higher levels of positively charged particles in the air and these affect our behavior. Are our dogs similarly affected by the light of the moon when it's full?
In the year 2000, a British medical journal published the results of two studies that investigated this topic. One of the studies was conducted in Bradford, UK, and found that more people went to the emergency room with dog bites during the period of the full moon. In another study, researchers at University of Sydney, Australia, found there was no actual correlation between dog bites and the phase of the moon. With results such as these, there's still no convincing evidence that the full moon makes it more likely that a dog will bite.
To make things even more confusing, one veterinarian from Colorado investigated the number of dogs and cats that were admitted to the University's veterinary clinic over a ten-year period. The findings: a 25% increase in the number of pets that needed treatment during the three nights of a full moon. Are the increased numbers because of the moon or is it because the evenings are better lit so more people and dogs may enjoy an outing, which may lead to accidents or injuries?
Even if the science doesn't back them, many pet parents find that their dogs do behave differently during the full moon. They might be restless, or bark more frequently. Why might this be the case? It's possible that the light of the moon makes it easy to see cats or wildlife wandering through the neighborhood, which would definitely make a dog agitated. Some dogs seem to be confused about the big white ball in the sky and bark at it purely because they don't know what it is. A third reason may be coincidence. Just because a dog behaves oddly at the time the moon is full doesn't mean that the moon is responsible for it. If that behavior occurred at any other time in the month when the moon is in a different phase, their pet parent would be unlikely even to notice what's going on in the sky.
In spite of the anecdotal stories from police officers and doctors, there is no evidence that the full moon has any effect on dogs' behavior. If a dog does something odd when the moon is large and bright in the sky, it's most likely due to pure coincidence.