What is this tree, please

Can anyone help with this? There  a tree on our boundary that I thought was an oak, fairly massive, but has this beautiful featherey red foliage and is dropping tiny pear-like fruits. I've seen stuff about Seckel pears and 'pere Manfredini' but I'm not sure.

Another day looking for where the boar come in. It feels sometimes like Lord of the Flies.