I’m often amused at how people attempt to fix pest issues, but as you can see it usually doesn’t work. Chicken wires look terrible and plastic spikes don’t bend and usually turn brown. The birds often find way to nest in the plastic and again it looks bad, really bad. I really dislike pigeons, they poop in their nest and if a baby chick dies they build right on top and continue raising new chicks. Spend the money and hire a Pest Management Professional, it will look good and be done right. We usually have seen it all before and can make recommendations on the work. Also a quick note, don’t put rocks or brick up there they might work for a time but will fail.