Hi GarethPlas
When hedgehogs hibernate, they don’t go to sleep, as such. The purpose of hibernation is to slow the metabolism right down so that they don’t need to keep feeding to keep it going. So it isn’t a question of keeping warm and cosy somewhere to have a nice long snooze, as some people think. Their body temperature needs to drop to a certain level to enable the metabolism to slow, but not so low that they get frostbite. So that the hedgehogs hibernating nest or hibernaculum needs to have just the right amount of insulation to maintain the hog at the optimum temperature. Luckily hedgehogs seem to instinctively know how to get that just right when they build their hibernacula.
Hedgehogs need to lay down two types of fat for hibernation. One type is to keep them ticking over and the other is to give them enough energy to boost their metabolism again when they emerge. So that before hibernation they need to feed up so they can, in effect, acquire sufficient fuel. So you can help the hedgehogs in the run up to hibernation by offering them good quality supplementary food, such as cat/dog/hedgehog food.
The three hedgehogs in your garden may or may not be related. Hedgehogs are solitary animals and normally only associate with other hedehogs for mating or if they are mothers with young. (Although we may be encouraging them to change their behaviour by providing feeding stations, where they may gather) Sometimes the young will stay together for a while after they have left the Mother. The Father hog is unlikely to ever recognise his young – the Mother is solely responsible for raising the hoglets.
It isn’t possible to reliably tell male from female by their size. Some adult females are larger than some adult males, although the largest males tend to be larger than the largest females.
Hedgehogs would not normally sleep in the same nest, once adult. Although there do seem to be more reports recently of hedgehogs sharing nest boxes. It’s possible that those are hedgehogs which have been over-wintered together with a hedgehog carer (because they may have been thought too small to survive hibernation without help). But normally each hedgehog will make it’s own hibernaculum. Even hoglets seem to know how to make them.
It’s possible one of the hogs might use your log pile, but it’s really impossible to know for sure. They may already have other nests or nest sites in mind, but also apparently some hogs actually move nests during the hibernation period – so the more potential nest sites they have the better.
Some hedgehogs (males in particular) may have already begun hibernation. Because they don’t have hoglet rearing duties the males are able to put on condition more quickly than the females and tend to hibernate earlier – but they will also normally return form hibernation earlier.
Good luck with the hog pile inn. I hope someone takes up residence. Don’t forget to also leave lots of leaves around – medium sized are best, as well as grasses etc, as the hogs will likely want to add to anything you have prepared for them. Ideally leave suitable nesting materials around all winter in case a hog wants to do some renovations or move to a new hibernaculum in mid-hibernation.
