The Hidden Reason Your Pet's Mood Might Be Changing
Seasonal changes can affect your pet's mood and energy, just as they affect you. Here is what you can do to help your companion stay happy and balanced all year long.
Reviewed by Dr. Tracy Duffner
Join the Bark & Whiskers™ Family
Sign up today for our FREE newsletter, packed with expert advice and insider tips to keep your beloved pet in tip-top shape.
View our Privacy Policy and Terms of Service.
STORY AT-A-GLANCE
- As daylight hours shorten, your pet's mood, sleep, and energy may shift, mirroring your own seasonal patterns and emotional state during darker winter months
- While it is objectively difficult to diagnose Seasonal Affective Disorder in pets the way we do humans, many pets seem to experience "winter blues" caused by reduced sunlight, less activity, and changes in daily routines
- Your emotional well-being strongly influences your pet's behavior — when you feel low or sluggish, your pet may respond with clinginess, fatigue, or loss of interest
- Encourage sunlight, movement, and mental stimulation with indoor play, consistent routines, and outdoor walks to help balance your pet's mood year-round
- Always rule out medical causes for behavioral changes first, and consult your veterinarian before giving supplements like vitamin D or omega-3s
When the days grow shorter and sunlight fades earlier, many people feel the difference. You might find yourself feeling more tired, less motivated, or even a little down as winter settles in. What you might not realize is that your pet could be feeling it too.
While there is no solid scientific proof that dogs and cats get Seasonal Affective Disorder (SAD) like humans do, there is plenty of evidence suggesting that our furry friends can experience their own version of the winter blues.
When the Seasons Change, so Do Moods
The world around your pet changes dramatically when winter arrives. The light fades earlier, outdoor time is limited, and the cold can make both you and your pet less active. These environmental changes can affect your pet's body and mind in surprising ways.
In people, Seasonal Affective Disorder is a type of depression that typically appears in the fall and winter months when there is less sunlight. This lack of light affects hormones that regulate mood, sleep, and energy, especially melatonin. Melatonin helps regulate sleep cycles and tends to increase in darkness, making us — and even our pets — sleepier during long winter nights.
Studies show that dogs have similar brain chemistry to humans, including pineal glands that produce melatonin.1 While researchers have not confirmed that dogs or cats can officially have SAD, there is growing agreement that changes in light, activity, and even owner behavior can affect animals' emotional well-being.2
Can Pets Really Get 'Winter Blues'?
You might notice subtle changes in your pet as fall turns into winter. Maybe your normally playful dog naps more often, your energetic cat hides more, or your pet seems clingier than usual. These behaviors often raise the question — is my pet sad, or is something else going on?
Veterinary experts say there is no scientific proof that pets experience SAD exactly as humans do.3 However, many pet parents report that their animals seem down or less active in darker months. Surveys show that up to one-third of pet owners notice seasonal mood shifts in their dogs and cats.4
This may not mean that your pet is depressed in the same way a human might be, but rather that they are reacting to changes in light, temperature, and daily routines — or even mirroring your own mood.
Your Mood Matters More Than You Think
Pets are incredibly attuned to human emotions. Research shows that dogs can recognize our facial expressions and tone of voice and even sense emotional states like stress, sadness, or anxiety. Cats, often unfairly labeled as indifferent, can also pick up on changes in human emotions.5
If you are feeling sluggish, withdrawn, or sad during winter, your pet may mirror those emotions. This is especially true for highly bonded pets who spend most of their time with you. When your activity level drops, theirs often does as well.
Imagine your dog's routine — in summer, you are taking long walks, playing fetch at the park, or relaxing in the yard. Come winter, walks shorten, outdoor play stops, and everyone stays indoors. Less sunlight, less exercise, and fewer stimulating experiences can quickly add up to boredom and a dip in mood for your furry friend.
Common Signs Your Pet Might Be Affected by Seasonal Changes
While every pet is different, there are some shared signs that suggest your companion might be feeling the seasonal shift. These signs can appear gradually, so it is important to pay attention to changes in behavior, appetite, or energy levels:6,7
- Sleeping and napping longer than usual, and less interest in play
- Hiding or avoiding interaction
- Changes in appetite — increased or decreased
- Clinginess or separation anxiety
- Increased barking or destructive behavior
- Aggression or irritability
- Reduced grooming or excessive shedding
If these changes seem familiar, do not panic; they do not necessarily mean your pet is depressed. However, they do signal that your companion might need some help adjusting to the seasonal environment.
However, before assuming your pet has the "winter blues," it is crucial to make sure the behavior is not caused by something else. Fatigue, appetite changes, or withdrawal can also be signs of underlying medical issues, such as pain or infections.
Schedule a veterinary visit if your pet's behavior changes noticeably. Once illness is ruled out, you and your veterinarian can work together to explore environmental and emotional causes.
Why Less Sunlight Can Affect Pets
Sunlight does more than warm your pet's fur. It helps regulate biological rhythms. The body's circadian rhythm is an internal clock that tells animals when to sleep, eat, and be active. When daylight hours decrease, this rhythm can be disrupted.
Less sunlight also means the brain produces more melatonin, which can make pets sleepier and less active.8 Combine that with shorter walks, fewer outdoor adventures, and less stimulation, and you have the perfect recipe for a slump.
It is not just the light, either. The temperature drop means more time indoors, fewer smells to explore, and less variety in daily life. For dogs and cats, both naturally curious and sensory-driven animals, this can be mentally dulling.
How Your Lifestyle Affects Theirs
Our pets depend on us for stimulation, companionship, and exercise. When our routines change, so do theirs. If you are less active, more tired, or spending less time outdoors in the winter, your pet's physical and emotional health can mirror that.
For example, if you skip morning walks because it is dark or cold, your dog might lose one of their main outlets for energy. If you keep curtains closed all day, both you and your pet miss the natural light that signals the brain to stay alert and balanced.
Even your emotional tone — your body language, voice, and facial expressions — affects your pet's perception of safety and contentment. When you are stressed or down, your pet senses it and may respond with clinginess, lethargy, or even anxiety.
Simple Ways to Boost Your Pet's Mood All Year Long
Luckily, helping your pet beat the winter blues does not require complicated treatments or risky supplements. Most solutions come down to creating consistency, stimulation, and sunlight in their daily life.
- Let the light in — Open curtains early in the day and position your pet's favorite bed near a sunny window. Even filtered sunlight helps regulate melatonin and serotonin levels, although not as effectively as direct sunlight. If possible, take short walks during daylight hours, even just 10 minutes of fresh air and light can make a difference.9
- Keep moving — Exercise is not just physical; it is emotional. Play fetch down the hallway, create an indoor agility course, or teach new tricks. For cats, toss toys, use a laser pointer, or hide treats to encourage movement. Activity helps release endorphins, our natural mood boosters, for both of you.
- Enrich their environment — Provide mental challenges through food puzzles, scent games, or interactive toys. For cats, create climbing opportunities with shelves or cat trees, or build a "box fort" for play and hiding. Mental stimulation keeps pets sharp and wards off boredom-related stress.10
- Stick to a routine — Predictability helps pets feel secure. Try to keep feeding, playtime, and bedtime on a consistent schedule, even if winter changes your work hours or energy level. A steady routine can comfort anxious or withdrawn pets.
- Get outside safely — Bundle up and go for daily walks when the weather allows. Fresh air and sunlight benefit both of you. Invest in pet-safe booties and coats for comfort. For cats, try short leash walks or supervised "catio" sessions when it is sunny.11
- Use indoor "sunshine" wisely — Human SAD lamps mimic natural light, but there is no evidence they work for pets.12 Still, having bright, warm indoor lighting during dark months can make your home more inviting and cheerful for everyone.
- Avoid unsupervised supplements — While humans often use vitamin D or omega-3s to help manage mood, these can be dangerous for pets if not prescribed by a veterinarian. Too much vitamin D can cause kidney damage or other health problems. Always check with your veterinarian before giving your pet any supplement.
Helping Both of You Through the Winter
Supporting your pet through seasonal changes can also help you feel better. Pets thrive on companionship and shared activity, and spending intentional time together, such as walking, playing, or simply cuddling in the sun, naturally boosts your own mood, too.
This bond is a two-way street. Just as your pet can mirror your stress, they can also reflect your calm, joy, and affection. Finding ways to stay active and engaged together helps strengthen that emotional connection, which benefits both human and animal well-being.
Try setting daily goals, such as a morning walk (even if short), 10 minutes of interactive play after dinner or even regular cuddle sessions near a sunny window. These small moments add up to a big emotional payoff.
Understanding the Emotional Lives of Pets
We often underestimate the depth of our pets' emotions. While they may not experience depression in the same complex way humans do, they certainly feel joy, frustration, loneliness, and comfort. Their emotions may be simpler, but they are no less real.
When you see behavior changes, it is important not to dismiss them or to humanize them too much. Your pet may be expressing discomfort, boredom, or a subtle response to environmental shifts rather than sadness itself. Still, that emotional state deserves care and attention.
Your role as a pet parent is to observe and respond. If your dog stops playing fetch, your cat hides more often, or your companion animal seems "off," that is valuable information. It is their way of saying something needs to change.
When to Seek Professional Help
If your pet's low energy, loss of appetite, or behavioral changes persist despite your efforts, talk to your veterinarian. They can help rule out underlying medical issues and may suggest behavioral strategies or, in rare cases, medication.
Sometimes, a veterinary behaviorist or certified trainer can help you reintroduce structure and enrichment into your pet's life. These professionals understand the emotional needs of animals and can offer targeted solutions to bring joy back into your pet's routine.
Brightening the Dark Days, Together
The changing seasons remind us of nature's rhythms — light and dark, activity and rest. Our pets are part of that cycle, feeling its shifts in their own quiet ways. As their caregiver, you have the power to help them adapt and thrive.
The best prescription for seasonal mood changes in pets is not a pill or gadget; it is connection. Regular play, outdoor time, and quality companionship light up their lives more than anything else. Keep the blinds open, the toys handy, and your heart open too. Winter may dim the sunlight, but it does not have to dim your pet's spirit or yours.
