It was water collected from my water butt, with dried oak leaves and some thin twigs from a Birch tree.
The outdoor enclosure is made using a cold frame measuring approx 120 x 90 cm. Using child labour, one of my sons dug down approx a meter . I lined the hole with a mesh cage then added a pond liner with some added holes (The area that this enclosure is, is very dry and has a number of trees close by) The soil was then returned with some added leaf litter.
One end is water, the other side has a hibernacula made from a plastic lidded box. This is about 30cm below ground level and has holes on the base, I will most likely add some leaf litter. There is section of pipe leading from the surface. I wanted the hibernacula to be accessible so that I could check the animals. On top of the box is a paving slab.
I am waiting a little while longer before I add the tigers, I think the soil needs to settle a bit. I also want to sink a line of bricks around the outside. :/ I may also use another slab to cover one end of the water. I am hoping to get this so that very little needs doing once the tigers are in.
Any suggestions for improving this will be gratefully received