Does the Moon Really Affect Your Pet’s Behavior?

August 8, 2012

By Linda Cole

In the horror movies, a full moon can bring out unnatural creatures of the night and send them wandering across the land. The moon plays a role in the ocean tides and gives us an awesome sight in the night sky when it’s full. Rumors and legends claiming that people and animals act strange during a full moon persist even today, but can the moon really affect your pet’s behavior?

For centuries, people have used a full moon to explain odd behavior and the common belief is it can have an effect on both people and animals, including pets. Dogs are supposed to howl more during a full moon, and cats yowl their mating calls with more passion. There have been attempts to study whether a full moon really can affect people abnormally and cause some people to become more aggressive or commit more crimes just before or right after a full moon. Some studies have shown increased visits to emergency rooms on days prior to and after a full moon, but there is no study that can absolutely say a full moon is the cause. It’s possible emergency rooms see more patients a few days before and after a full moon because it’s lighter outside at night and there’s a higher percentage of people out and about which could create increased chances of more accidents.

A study on pets was done in 2007 by a researcher at Colorado State University College of Veterinary Medicine and Biomedical Sciences. Raegan Wells, DVM, wanted to find out if pets were affected by a full moon. She wanted to know if, like people, pets experienced more injuries or got into more trouble during periods when the moon was full. She discovered a correlation between more emergency visits for both cats and dogs during the period just before or after a full moon. The study, “Canine and Feline Emergency Room Visits and the Lunar Cycle,” was the first of its kind and was published in the Journal of the American Veterinary Medical Association.

Wells went back over an 11 year period and charted emergency visits at the clinic and noted when full moons had occurred within that time frame. During the 11 year period, 11,940 pets were seen at the university’s veterinary medical center. The visits consisted of animal bites, epilepsy seizures, cardiac arrest, gastric problems, trauma, and other emergencies. The vets saw 9,407 dogs and 2,533 cats. According to Wells, there was a 28 percent greater chance for dogs and a 21 percent increased chance for cats to be seen by emergency personnel during periods of full moons.

This is the only “full moon” study that’s been done on pets, and researchers are still trying to understand if the increase was actually due to the phases of the moon or if there were other explanations that might increase a pet’s chances of having to visit an emergency vet. Wells said of the study, “It is difficult to interpret the clinical significance of these findings.”

However, in the wild, there is some evidence that animals are affected by the moon. For a couple of nights each year, there are hundreds of corals called reef builders that release their eggs and sperm into the water at precisely the same time. It’s considered to be the largest moonlight sex event on Earth. In another species of coral called Acropora millepora, scientists have discovered a light sensitive gene that seems to be more active during full moons.

Azara’s owl monkeys that live in Argentina forests are more active at night during full moons, and because they spend more time roaming around, they sleep in the next morning. Scientists also learned that the monkeys would stay put and not move about when there’s no moon.

A study done in 2006 discovered that prey is more apt to hunker down during full moons because there’s more light and it makes them easier to be seen by a predator. Researchers wanted to see if a full moon made a difference in a predator’s behavior as well. Over a period of four lunar cycles, they tracked three wild wolves during full moons and new moons and found that predators, like their prey, are less active during a full moon.

As far as our pets being affected by a full moon, the jury is still out. However, during periods when it’s lighter outside, we should remain vigilant and keep a close eye on our pets overall health, and be mindful of their environment to keep them safe and out of the emergency room.

Photo by Pieter Vanhaecke

Read more articles by Linda Cole

The personal opinions and/or use of trade, corporate or brand names, is for information and convenience only. Such use does not constitute an endorsement by CANIDAE® All Natural Pet Foods of any product or service. Opinions are those of the individual authors and not necessarily of CANIDAE® All Natural Pet Foods.

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  1. Brooke macwilliams says:

    My 16 year old dog just sits on my bed looking out the window. I literally JUST had to let her out of my room because she was super restless and kept walking around the bed. I had come up with a theory that it is just because it is brighter with the full moon, but that theory was shot when I remembered that I will take naps up in my bed throughout the day and she stays with me and sleeps. And many times, I come up to bed early to watch tv or go online, and she never has any problems sleeping even though it’s still bright outside. It’s bizarre. And this has happened for years. Also, my mom was dreading going to work tonight. She works in longterm care, taking care of Alzheimer’s patients, and she told me that they are awake all night every full moon.

  2. Anonymous says:

    For the past few nights my little chiaua-jack russel mix has been barking through the night and more aggressive during the day. I just came to the conclusion after many sleepless full moon cyles what might be causing this. I also saw increased behaviors in the elderly working in nursing homes.

  3. Anonymous says:

    thanks for posting.

  4. JZ says:

    I know with my dog it sure does.

  5. Priscilla says:

    That’s an interesting article! I’m sure the moon really does something on all of us. The Chinese always talk about Ying and Yang which is about the moon too.

  6. Mr. Pip says:

    This is really interesting. I have a few friends who work in emergency vet hospitals and they swear that more things happen on full moons and of course, holidays. The light theory is interesting – I can see this with people especially.

  7. CATachresis says:

    Oh I believe it! For animals and humans! We all go a bit crazy at times and I always check to see when it is full moon! lol

  8. Momsays she swears we turn into wild ones on full moon nights:)

    – The OP Pack

  9. Finn says:

    So interesting. I am going to have to pay closer attention to this next time!

  10. Father Tom says:

    I enjoyed reading this article. The fact that someone took the time to conduct an eleven year study speaks to the curiosity we all have!

    Thanks for sharing this 🙂

    Tom, Mom Julie, Tinker, Mitty & Anastasia