When a hedgehog gets cold, it enters hibernation (torpor) to survive, slowing its heart rate, breathing, and body temperature drastically, making it seem lifeless as it curls into a tight ball to conserve energy, relying on fat reserves; if a pet hedgehog gets too cold, it can be dangerous and require gentle warming to prevent it from trying to hibernate, which it's often unprepared for, leading to starvation.
Furthermore, hedgehogs are vulnerable to frostbite, even freezing, if their body temperature drops below 4C (39F); this is a significant danger if the temperature inside their nest falls below 1C (34F) and they may leave nests during very cold weather to avoid freezing to death.
Hedgehogs enter hibernation due to low temperatures and insufficient food. Vets cannot forcibly reverse true hibernation but can provide supportive care if a hedgehog is in torpor or ill. Symptoms include lethargy, low body temperature, and slow breathing.
It will need to be kept warm with either up against a radiator, hot water bottle or if you haven't got one an empty pop bottle filled with warm water. It is best not to warm the hedgehog too quickly with a heat source that is too hot, as this will take blood away from vital organs.
Hedgehogs feel best in temperatures between 75 - 85 degrees Fahrenheit. Temperatures that are too hot or too cold can make a hedgehog lethargic. Cold temperatures can cause your hedgehog to attempt to hibernate, which can be fatal in captivity.
Keep the box in a quiet, warm place: a hot water bottle filled with hot tap water wrapped in a towel can provide a gentle heat source – make sure it doesn't go cold! You can provide some fresh water and meaty cat or dog food, but don't try to feed the hedgehog directly.
If your hedgehog is unusually still in the evening—sleeping in short, restless bursts, waking and dozing repeatedly, or staying sluggish when they would normally explore—it can be a sign of unhappiness or even illness.
But this can also be common (especially with younger hedgehogs/hoglets) at any time of the year. Often they will shiver but more often than not, they will be frantically running around the place.
Check if the hedgehog:
Hedgehogs have prickly quills along their back to protect them from predators. They are shy animals and will roll up into a tight ball and hide their face if they are frightened. Always approach a hedgehog slowly and handle them with a small towel so you don't prick yourself on one of their quills.
But putting out a bit of food during winter allows them to top up any low stocks, and gives them a helping hand through the cold and harsh weather. Put out fresh food at dusk and don't forget a dish of fresh water!
Signs of stress
Many hedgehogs are busy and want to try to explore but a stressed hedgehog will be much more persistent and not easily distracted. The stressed hedgehog may also twitch or shake its head nervously. It is almost as if the hedgehog is saying “Sensory overload. I can't take it anymore.”
Wobbly hedgehog syndrome (WHS), sometimes referred to as progressive paresis/paralysis, is a progressive degenerative neurological disease of African and European hedgehogs. It has been noted with increasing frequency since the mid-1990s.
When temperatures drop, hedgehogs slow their breathing, heart rate, and body temperature to conserve energy. To an untrained eye, this can make them look like they've passed away but often they're not!
Hedgehogs tend to bond with their owners. They will remember your voice, your smell, and even your appearance.
They reduce their body functions to a minimum. With the energy reserves they have piled up by eating, they can survive for up to half a year without food.
However if you find a hedgehog staggering around, lying still (not in a nest), with flies around it or obviously sick or injured be it day or night, it needs urgent help. Sick, injured and orphaned hedgehogs are very susceptible to hypothermia.
Signs of dehydration in a hedgehog: Dull eyes Shaking/wobbling Collapse Out during the daytime Pale gums Sitting with hunched back Skin tenting What to do if you find a dehydrated hedgehog? Either stay with the animal or if this is not possible pick the hog up in a blacket/towel/jumper and place in a secure box.
Common conditions of pet hedgehogs include internal and external parasites, ringworm, cancer, pneumonia, gastrointestinal disease, and obesity. Signs of illness or disease are often vague and non-specific, such as lack of appetite and lethargy.
Cold to the touch: The hedgehog's body temperature will be much lower than usual, almost matching the surrounding environment. Slow breathing: Breathing will be extremely slow and shallow in the hedgehog - often difficult to detect. Curled up: Hibernating hedgehogs usually curl into a tight ball.
Many animals hibernate as a survival strategy for getting through the winter. Animals that lack the adaptations to remain active during the winter will either migrate to warmer climates or hibernate or become dormant.
Hedgehogs are native to warm climates and cannot tolerate the cold. If the temperature drops below 65 F then a hedgehog may begin to show some symptoms of hypothermia (often called hibernation, even though African Pygmy Hedgehogs are unable to hibernate).
Symptoms of stress
Hedgehogs often comfort their owners with cuddles, licks, and offer their paws or cuddly bellies for rubs. Their defences completely drop if they are able to form a close connection with their hedgie parents.
Eyes and ears: Hedgehogs have pretty poor eyesight, so they instead rely on their sense of smell to get around and hunt for food. Hedgehogs have short ears, mostly concealed by their fur.