Recycling in Nature

There appears to be a new owner of a cavity in this old cherry tree branch.  Last week I watched starlings bring small feathers in and out of the hole.  Today it is a nuthatch.  Obviously it is not always first come, first served in the bird world.  The nuthatch was bringing pieces of bark at first, then showed up with what appears to be part of a squirrel's tail.  Kind of icky, but perfect for the job.