With Bluebird photography theme you can easily set a single portfolio entry to serve as your homepage.

To do that you have to create a new portfolio entry, the go to Pages > Add New, give it a name (for example “Home”) and set the page template to “Single Portfolio Post”. Then choose your portfolio entry you just created from the dropdown menu. Finally, go to Settings > Reading and set your Front page to “Home” (or whatever you called the page you just created).