Gourd Nest

Someone (probably wrens) came by this gourd and filled it with sticks so no other birds would make a nest in it. Wrens have done such things before in my other nest boxes, I have had this gourd as  gift for years. This is the first year some bird has shopped and rejected it.
After this season I ought to sand it and put a coat or two of polyurethane on it. You never know in the future if someone will want to nest in it.