My best guess on this one. I have recorded many crow calls (both Fish and American) passing overhead during the "dawn chorus" but this is only one I've picked up at night.  According to Evans/O'Brien Flight Calls of Migratory Birds and Cornell's/AOU's The Birds of North America Online, Fish Crows are considered diurnal migrants and mostly silent in migration flight.  One of the things I enjoy about recording night migrants is capturing the unexpected, such as this Fish Crow.