Thanks for this tip. I think I shared somewhere how our tailorbirds found a strong fibre to stitch their nests. They were found pulling out plastic fibres from the old and sun-beaten window shelter of my room. Crows have found junk iron wires at construction sites. These wire pieces are removed from steel rod bundles or to bind rods for concreting. Crows take them away to make nests, along with twigs!
