All around the country we have settled in for Christmas; a gloriously festive time of delicious foods, heart-warming (yet rubbish) telly, a smattering of home comforts and did I mention the food? My home alone has been garnished for a fortnight already with homemade wreaths, paper snowflakes, glittery decorations and of course, the tree with its plethora of swinging adornments. I even have a wee badger hanging up there . But, while I am settling into to a wonderful life for Christmas – what are Mr. and Mrs. Badger up to?
Many people (and perhaps a much younger version of myself) think, understandably, that badgers hibernate during the winter. You can see it can’t you, a badger curling up in the nice warm sett for winter? One of their main food sources, worms, must be pretty hard to come by now and let’s be honest, if you can’t eat mince pies and watch ‘Love Actually’, going to sleep for all of a miserable British winter doesn’t sound too bad – Hedgehogs do it after all. But no, badgers do not hibernate and they still venture out of the sett, albeit less than other time of the year. In fact, during the Christmas period, female badgers undergo a very important part of the badger lifecycle
While badgers can theoretically mate anytime of the year, they tend to mate in spring or early summer when the weather is much better suited to romantic walks through the fields. Once successfully mated however, the female badger partakes in what I believe is a truly remarkable piece of biology: Embryonic diapauseor delayed implantation. Deep breaths here while we have a short (but interesting) biology session.
Typically with mammals, the female’s fertilised eggs (the very early stages of what will become her embryos and eventually cubs) will, soon after mating, become implanted in the walls of the uterus and grow and develop into the young animal before it is birthed. However, this isn’t what happens with badgers. As the term ‘delayed implantation’ may indicate, female badgers can halt the stage where the egg is implanted into the uterus until the environmental conditions are more ideal. This diapause is very rare in the animal kingdom and yet it is very beneficial. It is in mid-late winter, perhaps around this time, that the female with allow implantation to occur and began her gestation period of around 7 weeks. This means her cubs will hopefully be born around February and they will start to venture out of the sett in spring – all perfectly well organised.
One question really arises from this (if you followed it all so far) – why mate earlier In the year if you’re not going to actually think about getting pregnant until now? Why not just come into seasons in December and allow immediate implantation? Well there are a couple of different possibilities, which I’ll briefly outline.
The theory I find most interesting is a possible desire to increase genetic diversity. As if delayed implantation wasn’t enough, badgers also play host to another biological phenomenon; superfetation. Badgers can mate anytime of the year and superfetation means they can hold and birth young of numerous males at once. This means that a litter of cubs could be of different parentage. Delaying implantation therefore means that if they have numerous matings, they can be sure all eggs are implanted at the same time.
Mating earlier in the year may also be a reflection of when is simply the best time for badgers to mate. Spring/early summer is when badgers are out and about a lot and probably coming into contact with males (pretty crucial for mating) more often. The days are longer and they aren’t as busy with feeding loads and fattening up like they are in the autumn. All in all, it’s a perfect time to mate.
While not so supported, another interesting theory is that delayed implantation is a relic from days of badger history. Perhaps, like American badgers and honey badgers, European badgers were once a less social species. Maybe they only met prospective partners once in a blue moon and had to mate when they could and implant later. Maybe. If someone invents a time machine I doubt it will be very high on their list of question to go back and answer.
Anyhow, I definitely got lost down the biology rabbit (or badger) hole there, apologies. So yeah, badgers at the minute should be nice and fat. They’ll have been feeding lots over autumn to build up some fat reserves to last the winter and they’ll be coming out of the sett every now and again, especially if it is a bit more mild. The amount that European badgers leave the sett actually varies a lot with temperature. If you go to the south of Spain you might find that badgers hardly quieten down at all (except maybe for afternoon siestas) yet if you go to Russia, the badgers there will be entering a rather serious ‘winter sleep’ where they will reduce their heart rate and becoming pretty darn dormant.
So there you go, if you were wondering what the badgers are up to while you’re tucking into your Christmas dinner, they’re probably sleeping. And if you’re sleeping… well, they’re probably sleeping as well. Man, how does one become a badger?