It isn't just the eating. If you have a string long enough to catch on a tree limb, the bird is also in trouble. It could get wound around a leg of even it's body and it never could get loose. I say this happen when a lady hung washed fabrics on the line to dry and a bird found it was a lot of fun to unravel the thread. Fortunately we were ab le to unwind the bird and safe the life.