Mystery solved ???

I have been puzzled at the unusual rapid worn out rate of the string of my outdoor bamboo chicks. Was it due to the normal wear and tear/weather? One morning, I was attracted to the chirpings coming from my backyard. I went there, returned with my camera and captured several shots. The photograph explains it all! I suspect the bird (s) must have discovered that the string would serve as a useful material for its nest. If that is the case, I shall be glad to leave it that way. That's my guess. BTW, is this a Yellow Warbler (Dendroica Petechia)?

Have you had a mystery that kept you wondering??? Anyway, it's a good feeling that my (small) loss can become a (huge) gain to others. I welcome the bird family!