Kudos on pic...as an anecdote....this past summer, I was watched a male wren build a nest in one of my boxes this past summer...and then sing and display until he finally procured a mate....I turned away for a few minutes...and when I returned, I saw either a cooper or shinnie in junipers below the nest box eating his new found mate....sadly he didn't seem to find another mate all summer...he did swtich boxes but didn't find love again.