Crows and magpies strip anti bird spikes off buildings and use them to build their nests and make them more defensible. I like our neighborhood crows, I just wish they would stop hammering acorns with their bills on my roof at dawn. https://www.theguardian.com/science/2023/jul/11/crows-and-magpies-show-their-metal-by-using-anti-bird-spikes-to-build-nests #birds #crows