Huuuuiiii, what whizzes so fast across the bed? It is Wiesel Ozzy who is delighted with his new fleece toy. The commentary on the YouTube video says Ozzy is doing some kind of war dance. This is a typical behavior of weasels and ferrets when they are excited. It is possible that they use the seemingly haphazard, chaotic scurrying and flitting back and forth while hunting to confuse their prey so that they can catch them more easily.
With tame weasels and ferrets, this hunting behavior is no longer necessary as they are provided with everything they need by their favorite people. Nevertheless, this funny little dance can be found when playing when they have "conquered" or stolen a toy. A bit like the wild five minutes of cats, this behavior shows that a weasel feels good and has fun.
