Looking for some serious shower of knowledge about practices like this.

Yesterday night, I’ve encountered something very odd, on the common bordering wall between my house and my neighbours, the neighbours have put up “bird feet” tied together. It was hidden and not shown or easily seen, but I saw part of the toe nails of the birds feet sticking out so I went to see this thing.

Please help. I don’t know whom to ask, or if I can even talk about this in this sub, I apologise if I am not on the correct place.

I assume this has been there since very long. What can I do to protect myself and my family. I can give more info, if I can talk about it here. Thank you in advance.