Hollowed tree stump

I spotted this recently felled tree stump as I was going down the lane by the canal today. It seems to have become a casualty of the high winds we had a couple of weeks back. It stands on the edge of a wood on a very wet, muddy bank and opposite a rather lovely house - I suspect this is why it had to come down.

As you can see it is completely hollow in the middle. If you look closely in the bottom left of the picture there is a rather magnificent looking black fungus - I'm not sure if this is a cause or a symptom of the tree dying - any blippers out there know?