some advice needed

just got back from my hols and discovered my neighbour has added even more wire along the top of the fence between our properties, before it was just down the rear fence!!   Its attached using very long screws screwed into the top of the fence, and then wire is strung between them all along the top, its her way of deterring the birds from sitting on it, and also to stop them pooping on her fence (cos then her gardener has to scrape it off!)

We live on the edge of open ground and have a wide variety of bird and wildlife around us, with many birds visiting the feeders in our garden, and blue tits nesting annually too.

It looks dangerous for both birds and other animals to my mind, as they could easily get trapped and caught in it, but I am not sure of the legality of it, can anyone please advise me?