Translation:A bird ate the pie. So we ate the bird.
i support TARDISToni on this. in this context to me "then" has a touch of understatement, considering the bird's fate and this very calm and practical approach to make the best of the "stolen pie" situation. Just think of sitting in a taj drinking some 'Iw Hiq and reporting the day's events to your friends, (in German my conclusion would be "...tja, wir haben dann den Vogel gegessen...")