Alvin ASBO 😻🐾😹

I've had a few messages from folk saying they've read hedgehogs in hibernation get up and change nests, and that well fed healthy hedgehogs can chose to be up and active in the winter. This is nonsense. Yet another myth that is based in ignorance, and is blindly copied and pasted onto many sites, sometimes even by ill-informed rescues. The facts: A great deal of work goes into the making of a hibernacula, and a hedgehog may take weeks constructing it. And while it's true a hedgehog often builds 1 or 2 others, these are 'Plan B' nests - to be moved into only in emergency, like flooding or disturbance, making the main nest uninhabitable. They will stay in the main nest all winter long. They may rise for a top up of food, particularly during the first couple of weeks of hibernation, but this will be for one night only and they will return to the same hibernation nest. All healthy well nourished adult hedgehogs hibernate. This is hard-wired into them, and has been for 15 million years. Leaving out a dish of cat food won't alter it. Right now, the only hedgehogs you'll see up are those who are not able to hibernate. This will be for 3 reasons: 1. They are sick. If a hedgehog is ill with an infection or internal parasites they are not able to enter the complex and dangerous state of hibernation, and need treatment from a rescue (never a vet). 2. They aren't old enough. A hedgehog needs to be fully grown and of a sufficient weight, with a deep layer of fat, to be able to withstand hibernation. Late born autumn babies won't have achieved this, and need taking into a rescue to be assessed (99% will also have internal parasites that need treating). 3. They were taken in as babies to a rescue where they grew and were treated and have been newly released. A hoglet in a rescue, confined to a cage in the warm, will gain weight rapidly. This is fine and good, but the fat they grow will be white fat. All mammals (including us) have 2 types of fat: A) White fat, which is quickly made and stores energy. B) Brown fat, which burns energy to create heat. Cold temperatures activate brown fat, and it's brown fat that helps maintain body temperature - essential during hibernation. Therefore, in order to survive hibernation, a hedgehog needs to grow mostly brown fat. So if you have a hedgehog newly back from a rescue, sure that he's fit and healthy but you are wondering why he hasn't hibernated, this is why. Google "brown fat vs white fat" if you'd like to know more. Please keep providing good food that has meat as the 1st listed ingredient, to nourish these poor unfortunates who may be lucky enough to find your garden.