Why Do Dogs Make Nests?

It’s cute to watch your dog burrowing into the blankets on a cold winter night. But there are times when dogs make nests that are signs of pregnancy or false pregnancy. Although it’s normal for some dogs to cuddle under blankets or scratch out some dirt to sleep in, burrowing into a closet or other more serious nesting behavior might be a bad sign.

Why Do Dogs Make Nests?

Several serious illnesses can increase the chance of your dog experiencing a false pregnancy, which is a major cause of dog nesting behavior. If your dog isn’t spayed, she might be pregnant.

Sometimes, your dog is making a nest just because that’s the comfier way to sleep. Who can fault a dog for wanting to drag her bed into the sun or burrow under the blankets? But more serious nesting behavior—like shredding blankets, digging into small spaces, or over-grooming—is often a sign of pregnancy, real or imagined.

Nests Are Comfortable

This is the most benign reason that your dog could make a nest. Whether you’re watching a chilly greyhound burrow into the blankets or a hot husky scratch out some cool dirt, nest-making is normal for many dogs. Some dogs are habitual nest-makers, arranging blankets and bedding to their liking almost every day. Other dogs might only engage in nest-making behavior when they’re particularly uncomfortable.

If your dog is male, this is the most likely reason that he’s building a nest. Spayed females who don’t have their ovaries anymore are also less likely to experience a false pregnancy. For the vast majority of dogs, therefore, nesting is no big deal. It’s just a sign of a smart dog making itself comfy!

That said, nest-making behavior that appears compulsive, stress-based, or pain-based is a cause for concern. Bring it up with your vet.

Your Dog Is Pregnant

If your dog is an intact female, there’s a chance that her nesting behavior is related to pregnancy. Expecting mothers naturally want to make a safe area for their newborn puppies. Even if you didn’t realize your dog went into heat or you don’t think she ran into any intact males while she was in heat, there’s a good chance that your female dog’s nesting behavior is due to pregnancy.

Get your dog to a vet as soon as possible to check in on whether or not she’s pregnant. Your vet can also help ensure that the mother and her new puppies get all the care that they need. Even if your dog seems in good shape, working closely with your vet is imperative to keep the mother and the puppies healthy!

Intact females (and some spayed females) can also experience a false pregnancy. See below to learn more about this phenomenon.

Your Dog Thinks She’s Pregnant

False pregnancy, known by vets and scientists as pseudopregnancy, occurs when a female dog’s body believes that she’s pregnant. Your dog might show physical and behavioral signs of being pregnant, including weight gain, nest making, enlarged mammary glands, appetite loss, vomiting, collecting of objects, and even aggression.

A recent study on pseudopregnancy found that most dogs who experience pseudopregnancy are intact, but it’s still possible in spayed dogs. False pregnancies generally occur within four to nine weeks of the female’s last heat cycle, especially if she ran into any male dogs during her heat cycle but didn’t become pregnant. Behavioral changes, such as nesting and collecting objects, are more common than physical changes. About half of the dogs in the study were treated with medication to help end the pseudopregnancy.

False pregnancy isn’t well-studied or well-understood, but some underlying medical conditions can make irregular heat cycles (and therefore false pregnancies) more common. It might be a stretch to say that nest-making behavior is a symptom of these diseases because of the tenuous relationships, but it’s still good to check things out with your vet. Both hypothyroidism and liver dysfunction might be possibly linked to false pregnancies (and therefore nesting behavior).

Signs of Dogs Making Nests

Everyone has a slightly different definition of nest-making behavior in dogs. For some people, a dog who drags his blanket into the sun is making a nest. For others, the dog needs to burrow, shred bedding, and groom herself to be truly nesting.

Nesting behaviors include:

• Dragging blankets or beds to a new spot
• Digging or burrowing into small spaces
• Scratching out dirt, soil, or even bedding to create a depression
• Shredding blankets to put into a given spot

Dogs that are pregnant or experiencing a false pregnancy might also collect toys or stuffed animals, over-groom, or start to defend their nest from intruders.

How to Solve Your Dog's Nest-Making Habit

If your dog is a habitual nest-maker who just likes to be comfy, there’s no need to worry. Purchase cheap blankets specifically for your pup that you won't worry about getting shredded or dragged around. But if you’re seeing a sudden change in your dog’s nest-making behavior, it’s time to get in to see the vet. Vet visits are important whether your dog is experiencing a true or false pregnancy, as both may require medical intervention.

It may help your vet make a diagnosis if you film your dog’s new behaviors. Take note of your dog’s body postures, eating habits, and other pertinent medical information so that you’re ready to answer your vet’s questions fully when you get in.