Magpies v. Woodpigeons?

A couple of weeks ago we had both a pair of magpies and a pair of woodpigeons visiting our garden to feed.  The magpies were refurbishing the nest in a fairly youngish beech tree a few gardens away, that they used last year.  Meanwhile, the woodpigeons were prospecting the ivy in the ash tree at the bottom of our next-door neighbours garden where they too had nested last year.

Then we had some high winds and rain. 

 A little over a week ago the pigeons arrived to feed but one had what looked like a severe wound to its breast.  The pair came for a day or two but then only the uninjured one arrived and that's how it's been ever since.  Whilst this had been happening the magpies appear to have been dismantling their old nest and moving the pieces into the ivy where the pigeons had been scouting.

Could it be possible therefore, that the magpies have violently ousted the pigeons in favour of a better nest site?  I don't think the injury to the woodpigeon was caused by the weather, nor do I believe that Paddy the Cat was responsible because he comes indoors at about 3 p.m. and stays in until we let him out again at around eight in the morning.  He also pops in regularly throughout the day.

It's quite sad to see the woodpigeon always alone so I do hope it will find another mate soon.    

Dotty