Keeping your hamster cool in summer is hard! The poor little guys are covered in fur and they're not able to sweat. Given that they’re curious and usually try to chew everything within a paws length it isn’t easy to add cooling pads and other commercially available cooling products to their cage. But all is not lost. There are a surprising number of things you can do to help keep your little one cool!
What temperature is too high for hamsters?
It won’t surprise you to know that there’s no real consensus about this online! Where hamsters are kept in laboratories, the UK Home Office requires hamsters to be kept at a temperature of 20-24°C. However hamsters are able to cope just fine in temperatures outside of this range. Personally, from having observed Flamey’s behaviour closely during hot temperatures, he seems fine between 18°C and about 23°C after 23°C he begins to display behaviours that indicate that he’s too warm. The warmest he’s ever been is 26°C when we had some 30°C + temperatures last year and at that point I was quite worried about him. Luckily he was fine and he was only at that temperature for an hour or so before it began to cool back down.
Just because science says your hamster should be kept at a certain temperature range, doesn’t mean your hamster will agree. Everyone knows someone who’s always cold and who wears a jumper until the mercury hits 30°C, and most people know someone who’s just always too warm and wears shorts even in the winter. Hamsters are no different, what’s comfortable for each of them will Vary.
Measuring the temperature of your hamster’s environment
The best way to monitor temperature is to get a thermometer which you can put on or next to your hamster’s cage. It doesn’t have to be expensive, it just has to work.
Simple thermometers
This is the one I use with Flamey:
(Not an affiliate link, other thermometers are available!)
It is easy to use, it was easy to set up, it doesn’t eat batteries and it works via Bluetooth so I can check the temperature on my phone. I’ve had no issues with it ever. However, if I was choosing a new one I might be tempted to go with one that I can read when I’m away from home as well because Bluetooth means I can only read the temp on my phone when I’m not too far from the thermometer.
Smart thermometers
You can use a smart thermometer which will allow you to check the temperature when you’re away from home. Having said that, unless you plan to return home if the temperature is too high then knowing the temperature away from home might not help you. Having a smart thermometer might allow you to set up automations or use the thermometer with other devices. For instance, you could set up an automation via Alexa and a smart plug to turn off a heater when it gets to a certain temperature. Or even just to alert you when the temperature gets to a certain point.
Meat thermometers
OK, hear me out. This one is a little extra! Last summer we had some days that hit 35°C or higher and it was an absolute nightmare trying to keep the house cool and by extension to keep Flamey cool. At one point I was losing my mind because he kept dissapearing into his deep bedding and I thought he’d be getting a lot warmer down there than he would be in his above ground hides. I used a meat thermometer to measure the temperature under his bedding and I found that it was a lot cooler under there than I had thought. So it gave me peace of mind. If you’re packing ice around the base of your cage or putting the cage on a cooling mat, then a meat thermometer might help you to check that it isn’t getting too cold in your hamster’s fluff.
Signs that your hamster is too hot
Science may say that hamsters are best kept between 20-24°C but as soon as we start to hit 21°C Flamey starts to get uncomfortable. being able to spot the signs that your hamster is too warm will help you find the perfect temperature for them.
Generally when hamsters are too hot they start to exhibit the following behaviours:
- Lethargy
- Sleeping outside their hides on the surface of their base substrate
- Drinking more than normal
- Unengaged with the environment
- Confusion and disorientation
- Lack of grooming / unkempt fur
- Stress behaviours such as bar biting
Of course some of these are also signs of sickness as well so it’s important to see if these behaviours continue once your hamster has cooled down. Or if your hamster was displaying these behaviours before the temperature changed you should consult a vet.
Ways to keep your hamster cool
Here are 21 different ways to keep your hamster cool.
Move your hamsters cage to a cooler place
This one is definitely a must for me since I have an attic conversion which is where Flamey lives most of the year. It gets really hot up there. As soon as it hits around 20°C outside, the attic conversion starts to register 25/26°C. As the summer kicks in, I move flamey’s cage downstairs to the back of my house because it’s cooler. The room I choose to put him in isn’t used often, so I can leave the curtains shut to keep the sun out in the day. It also has patio doors so I can leave these open in the evening when it gets cooler.
It isn’t always possible to move the cage, especially if you have a huge one, but if that’s the case, consider setting it up in a cool area to begin with. It is far easier to keep a hamster warm than it is to cool down a hot room.
Use a fan
Having a fan can help to circulate cooler air around a room. It doesn’t necessarily reduce the temperature, but it can help your hamster to feel a bit more comfortable.
It is important not to point the fan directly at the cage since the air stream will likely be too strong for your hamster. Setting the fan to oscilate at a good distance from the cage will just provide a cooling breeze for your hamster.
This one can be a bit of a trade off since hamsters generally don’t like noise, especially mechanical noise. I have found that Flamey doesn’t like the noise of a fan and will mostly hide when it’s on so it can feel a bit pointless to have it on sometimes!
Use curtains to stop direct light entering a room
Direct sunlight shining into a room will make it warmer. If you have a room that lets the sunlight in during the warmest times of the day, consider keeping the curtains closed. This will keep the room cooler. If you have thermally lined curtains or white curtains this will help more than thin or dark curtains.
Keeping your curtains drawn is especially good if the sun would usually shine on your hamsters cage since it's better to keep the cage out of direct sunlight.
Keep water in the fridge for your hamster
When you’re topping up or replacing your hamster’s water, you can use water that you’ve kept in the fridge so they have cooler water to drink. This helps to reduce their core temperature when they drink it. Rather than topping it up all the time, I tend to put cold water out for Flamey at times he's due to get up, or right after he's gotten up.
Handle them at cooler times or in cooler areas
If you have a hamster who loves their out of cage time or playing with their human, try to handle them earlier in the morning or later in the evening, or play together in a cooler part of your home. The increased activity and the extra warmth from your hands and body can contribute to making them feel uncomfortable in the heat. It tends to be cooler in the morning and the evening so this may be better for play time. You can also consider letting your hamster run around in the bath, on a tiled floor, cool kitchen worktop etc as a cooler area to play in. Just make sure you're keeping an eye on them if they're in unusual areas.
Put your hamster’s sand in the fridge
Hamster safe sand is a naturally cool substrate and your hamster will likely be drawn to it in hotter weather. You can give them a cooler space by giving them sand from the fridge. During summer, I have 2 sand baths going for Flamey. One I keep in the fridge and the other in his cage and I swap them regularly especially before he's due to get up. This provides him nice cool sand to roll in or just sit in which can help reduce his temperature and keep him comfortable.
Sand is perfectly fine in the fridge, but you should make sure that the sand is in a sealed bag or container so that it doesn't pick up any smells from the fridge, and so that it doesn't transfer any potential bacteria from your hamsters sand to your food. I usually keep Flamey's sand in a zip seal bag.
Give your hamster soil - you can also put it in the fridge
Hamster safe soil is naturally a little damp, so it’s a really nice cooling substrate in summer. The dampness makes it feel a lot cooler to the hamster. It also dampens their fur a tiny bit which will help them feel cooler. You can also put soil in the fridge to provide them with a very cooling substrate. Soil holds its temperature slightly better than sand because the large particles of soil trap air between them. I would be tempted to only do this if the temperature was especially hot, say over 22°C because soil tends to be pretty cool anyway.
Chill slates and ceramic tiles
If you have any slates, stones or tiles in your hamsters cage you can put these in the fridge too. Some materials are better at holding temperature than others. Tiles are naturally cool, but they do warm up relatively quickly. Slate tends to hold temperature pretty well. You can pop these in the fridge before giving them to your hamster, this then gives them a nice cool surface to sit on.
Just like with the sand, you could keep a few slates or tiles in the fridge and a few in the enclosure and then swap them just before or as your hamster gets up. Again you should make sure to keep them in a ziplock bag to prevent any smells or bacteria from transferring.
Freeze treat mixes and seeds
You can freeze your hamsters food and treat mixes! This won't work for every type of food, but if you have food that is dry like seeds, Mealworms, dried flowers, basically anything that has hardly any moisture at all, then you can freeze it and give it to your hamster out of the freezer without any issue.
I have tried this with Flamey a few times, but I scatter feed him so it's not a great option for us. Flamey rarely eats the food I have scattered right away so it feels pointless. However if you give your hamster food from a bowl this could work.
I also freeze fruits for Flamey, before he’s due to get up I might pop a frozen blueberry or blackcurrant in his cage, it defrosts quickly but it is usually quite cold when he goes to eat it.
Put bedding in the fridge
In the same way that you can put sand in the fridge, you can do this with bedding too. You could fill a ceramic hide with bedding from the fridge to make a nice cool space for your hamster. This is probably more practical for above ground hides since you’d need a lot of fridge space to cool your hamster’s base substrate.
Use frozen water bottles or ice packs outside the cage
Popping frozen water bottles outside the cage at strategic points can give your hamster a cool place to sit in. I usually pop one next to Flamey's sand and he has a great time licking it through the bars of his cage! I even managed to capture it for TikTok.
You can pop frozen bottles next to hides and their favourite sitting spots which help to keep those areas cool. You can prevent puddles outside the cage by placing a flannel or a towel under the water bottle.
It's important to make sure they're placed in such a way that they won't be getting your hamster or their bedding wet. It's also important to make sure that you don't do this to every hide and sit spot. You want your hamster to be able to go to a different hide if they're getting too cool.
At the time of writing you can pick up two ice packs in Asda for £2 and you can pick up flannels (or face cloths) for just 80p in a variety of colours and I find these are enough to catch and absorb drips from ice packs or frozen water bottles. It’s a really inexpensive way to provide cooler areas for your hamster.
Put frozen things inside the cage
There are some commercially available hides and ceramic pots that allow you to put frozen things inside the hamster’s cage. There are likely ways to DIY this as well, but remember anything frozen you put in your hamster’s cage has to be safe for them to chew on and be free of condensation so they don’t get wet.
Pop frozen things on top of or next to the hide you know they're in
You can put frozen things on top of or next to the hide you know your hamster is in if they’re using above ground hides. It is important not to do this to every hide your hamster has, but just choose one or two to always have something cold next to it. Your hamster will learn that those specific hides are cooler and will use them if they are too warm. If they get too cold snuggled up to an ice block they’ll be able to move to a hide that’s a little warmer.
Get a ceramic hide and freeze it
Ceramic hides are an essential for hamsters in hot weather. They’re much cooler and they hold the cold pretty well. It’s the same principle as having a ceramic tile in your hamster’s enclosure, but it’s somewhere they can sleep and feel safe. You can also put ceramic hides in the fridge before giving them to your hamster if the weather is particularly warm. If you don’t have a ceramic hide or it’s going to be a particularly hot day and you want your hammy to have more options, you can put a ceramic cup, mug in the cage on its side or pop in a ceramic bowl they can get in and out of and it will have the same effect.
Put a damp towel in the freezer then lay it over the cage
When a fan just won’t cut it and the weather is having a mare, you can put a damp towel in the freezer. Once frozen you can drape this over part of your hamster’s cage to help provide a cooling area for them. As in other tips though, it’s important to make sure that you don’t cover the whole cage so that your hamster can choose to go to a different area if they are a little too cold. Also make sure to not restrict air flow to the cage when you do this.
Add extra water
When the weather is really warm hamsters tend to drink more. Putting extra water around the enclosure can encourage hamsters to stay hydrated. If you use play pens and out of cage areas make sure your hamster has access to water in these areas. It doesn't always have to be in a water bottle. It's fine to improvise in a play area. Flamey has 3 play areas and a play pen and I tend to use these scoops as little watering holes for him when he's on the move outside his enclosure.
Give your hamster cold treats like watermelon
Watery foods are a great way of keeping your hamster hydrated, but they also have the added bonus of being naturally cooling. Watermelon, berries and cucumber are great treats to give straight from the fridge. Another trick is to use frozen fruit. I often freeze blackberries, blackcurrants and strawberries for Flamey. In the hot weather I put them into his cage when they're still frozen. They defrost quickly, but they also stay colder for longer. You can get packs of mixed frozen fruits from supermarkets which are often sold as smoothie mixes. These mixed packs are a great way to inexpensively give your hamster a wide variety of fruits and veg if, like me, you don't want to be constantly eating all the fruit left over from when your hamster has had just a few pieces! As long as you make sure the fruit hasn't had anything added like sugar, sweeteners or fruit juice it should be a safe option for your hamster.
Don't change the amount of bedding
It might be tempting to give your hamster less bedding. After all, in the summer a lot of people swap their fluffy winter duvets for thinner summer duvets. But hamster bedding has the ability to keep your hamster cool in summer and warm in winter. Keep the amount of bedding the same so that your hamster can continue to burrow. If your hamster feels that it’s too warm in their burrows they will seek out cooler spaces.
Add above ground hides
Give your hamster a choice of hides. Having deep bedding that they can burrow in and a selection of above ground hides will help them to regulate their own temperature which is their natural instinct. Provide cardboard or wooden hides with bedding and ceramic hides with or without bedding and let your hamster choose where they are most comfortable. When the weather is extremely warm, Flamey will often sleep in his sand, but he doesn’t for the rest of the year. So during summer I provide him with a covered over sand box so he can feel like he’s in a hide. This makes it more private for him when he wants to sleep in his sand and gives him another option if he gets too warm.
Use a Cooling Mat
A cooling mat is a good way to help keep your hamster cool, but they’re often made of materials that are easily chewed, so you need to watch carefully if you’re going to try this. You can put the cooling mat under the cage, or place it on one side of the cage to provide a cool area.
Make use of play pens
This one is a bit left field, but it’s worked for me. If you have a play pen that’s portable and it has a hide in for your hamster to sleep in, you can easily put your hamster somewhere much cooler in your house. Flamey’s play pen has a bit of sand, beech chips and a few toys, water and a hide.
He doesn’t play in here a lot but we use it to go to the vet and sometimes he likes to sleep in here. If he falls asleep in here on a warm day I can put the whole thing in the bath or on the tiled bathroom floor. The bathroom is the coolest place in my house so Flamey gets a nice cooler area to sleep in.
As a bonus this also works great on bonfire night. I can put him in the quietest spot in the house so he doesn’t get scared. Luckily I also have a camera that I can use to keep an eye out for when he wakes up and wants out of his play pen.
Keeping your house cool
Part of keeping your hamster cool is knowing how to keep your house cool. Here are some general tips;
- Keep doors and windows closed - it feels counter intuitive, but if you open your doors and windows at the wrong time of day you’re just going to let hot air in. Keep doors and windows closed in rooms when the sun is directly on them. Try opening doors and windows early in the morning and late in the evening to let the cool air in. This should have the effect of trapping the cool air.
- Keep blinds and curtains closed - again this will stop the sunlight streaming through your windows and warming up your space. Heavy white curtains will provide the best protection against the heat as they will bounce the sunlight back out of your window.
- Fans are a good way to feel cool, but often they just move air around a property. in a warm room, pointing a fan at the door or window can help to move some of the heat out of a room.
- Reflective privacy film can be added to your windows to bounce sunlight back outside. It is cheap and easy to apply and can be especially good if you dont have white or light coloured curtains and you want to keep your house cool.
So there you have it. A bunch of ways to keep your hamster cool, hydrated and happy during the summer!
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