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A message from Russell: My foster parents have written this page as my paws aren't good on the keyboard, and besides, I'm the one that has done all the hard work digging my own burrow!
Introduction
When we placed Russell into his outside enclosure, we were a little uncertain of how he would go about digging a burrow. We knew as foster parents, that it wasn't our job to dig a burrow for him as it would be one of the skills that Russell would require to be able to survive in the bush. So how do you tell a wombat how to dig a burrow? Luckily, Russell managed to figure this out for himself...
How we started Russell off digging his burrow
Before we put Russell outside, we dug a square hole in the ground approximately 40cm x 40cm (15") wide and about 20cm (7") deep in his enclosure. We placed three bricks around the hole so that they formed three sides and then placed a concrete slab on top. The effect was a hole in the ground, covered by a piece of concrete (like a little house). We placed one of the towels that we had been feeding with Russell into the hole, so that it would have his (and Donna's) scent on it to give the message that this was a safe and secure place. We introduced Russell to this arrangement and were delighted when he went into the hole and had a bit of a dig at some of the hole walls. He scrambled back out and in again a number of times, and we believe he got the idea that this spot was meant for him and that we had given him a little head start. We left him out in the enclosure that night and anxiously hoped that he would get the message to dig. Given that it was mid summer when we placed Russell outside, and that the Canberra summer is quite warm (even during the night) there was no chance of him suffering exposure or chilled.
 The next morning we arose to find Russell hadn't dug anything - and he wouldn't the next night either. However, after the third night of being left in his enclosure and in his makeshift house, we awoke to find that he had dug into one of the walls of his hole, and quite a distance so that he could immerse himself into his new 'burrow'. However, he could only go in head first and had to back out with his rump when he wanted to come out. Still, it was a great start and the fact that he had dug this part for himself was very encouraging. It also showed that digging a burrow was part of a wombat's nature, and although when we received Russell, he would not have had his mother show him how to dig this, there was obviously some instinctive part of him that knew what to do. Our initial hole in the ground had given him the idea that it was OK to dig and that he should make something that was comfortable for him to stay in.
Russell's first modifications to his burrow
 Over a period of a few months, Russell made some modifications to his burrow. We knew when he had done work, as there would be freshly deposited soil just outside his burrow entrance. We made a habit of clearing this away, as with the clay nature of the soil in our backyard, this would compact over time with Russell's comings and goings and form a 'rise' or ridge in front of his burrow. As he was in an enclosure, and drainage wasn't all that great, we didn't want to create a situation where the rise in front of his burrow would cause water to flow into his burrow when it rained. We wanted at least the opposite. In a normal wombat's burrow, there would be no one to clear this away and so the soil just sits there, is washed away by rain, or more commonly, is compacted by the wombat's weight in its comings and goings into its burrow. This mound of dirt outside the burrow acts as an insulator for wombats in the wild. It helps keep it cooler in the hot months and warmer in the cold months so there is a purpose for this soil.
Russell's next major modification was to dig himself a bedding chamber. He did this by digging slightly upwards from his burrow entrance and making a small space (or chamber if you like) in which he could lie down in. Russell pulled in dried native grass and leaves into his bed chamber to make things a little more comfortable to lie in. One time we accidentally left a gardening glove in his enclosure, and that too, went into his bedding chamber as it had our scent upon it and was obviously a source of comfort. As the chamber was slightly elevated, it meant that his burrow entrance could get wet, and Russell would stay nice and dry if it rained.
Russell makes more modifications to his burrow
Unfortunately, Russell being a little digging machine (and an overachieving one at that) made some more modifications to his bedding chamber and dug through to the surface. This was how we could see what he was doing. We remedied the situation by placing two flat, large concrete slabs on top of the new 'hole' that he had dug from up in his bedding chamber. One slab was the original roof of his makeshift house which we put him when he first went outside. We also removed the other bricks which were supporting this slab at the same time so that this construction wasn't around anymore. In the bush, Russell would just move onto another place to dig a burrow. Unfortunately, with space being at a premium in his enclosure, putting some concrete slabs over his new hole seemed like the best idea at the time. It provided him with cover, they were sufficiently heavy so that he couldn't move them easily, and they were a bonus for us if he ever got into trouble in his burrow - we could just lift them up and retrieve him. Russell was still able to slightly move the concrete slabs even though he was around 12kgs (26.5lbs) in weight and the slabs must have weighed around 20kgs (44lbs). We were astounded at the brute strength of a creature this size.
 The next modification that Russell did was to solve the problem of him coming out of his burrow backside first. This was simply done by digging another entrance! He did this by digging down from his bedding chamber and then up again to the surface. This meant that he could go in one entrance, sleep in the middle in his bedding chamber, and then move forwards and out of his burrow via the other entrance. He also dug a small side passage off his bedding chamber which is consistent with the line if he entered via his new burrow entrance. We're not too sure why he dug this, or if it serves any purpose at all - maybe it's just a whim of the wombat.
As Russell grew in size as well, he had to make modifications to his burrow so that he could fit inside. When we used to see a pile of dirt in the mornings outside one of his entrances, we naturally assumed that Russell was making some major extensions to his burrow. Of course, given that he was still growing, he had to make enlargements to his burrow so that he could squeeze through. In the wild, Russell's backside in his burrow would be his best line of defence. Any animal that was foolish enough to go down a burrow with a wombat inside was lucky to escape with it's life. All Russell would have to do is reverse his tough backside up against the animal's head and push it up to one of the walls of his burrow. Asphyxiation, or having the skull of the animal crushed are the two likely alternatives here...
Conclusionary notes
 When we released Russell, he had dug a wonderful burrow that would prove to be a legacy for other wombats that we would care for. Abigail was our next wombat that was to be placed into the wombat enclosure, and when she saw the burrow (and obviously smelled Russell's scent) she ran in and out of it a number of times. We felt guilty that she didn't find a wombat, but now she has made this burrow into her own. No additional dirt has been dug (yet!), but she uses the bedding chamber for sleeping in during the day.
Have a look at our page on other wombat burrows in the area. These burrows are from various reserves and nature parks within the Canberra region.
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