A purple Martin house should never be offered without Starling resistant entry holes. (SREH). That is my opinion and I have seen firsthand the damage these starlings can do. I have chosen to use the Conley II entrance. Opinions vary on the ideal SREH but when positioned properly I have yet to have a starling breech a Conley II. SREH’s are the number 1 greatest development to come along for purple Martin housing and purple Martin landlords in my lifetime. ChirpyNest is the second.