Fungus or slime on tree

Fungus or slime on tree

Observation - Fungus or slime on tree - UK and Ireland. Description: This transparent membrane covered around half of this large tree in Rosedale Abbey. Is it a fungus? I have 2 more photos of it.

This transparent membrane covered around half of this large tree in Rosedale Abbey. Is it a fungus? I have 2 more photos of it.