Bird Identification: Common or Boat-tailed Grackle Nestling?, 1 by LupineNight

LupineNight wrote:
Someone brought in this almost-fledgling grackle to the emergency veterinary hospital I work at. We always get a lot of kidnapped babies this time of year. We're all tired of driving to the rehabber place, so I am going to feed this kid until it's ready to raid the wal-mart parking lot ;). I think it should be able to stay outside but with access to it's "nest" box and food in another week. Anyway, I was wondering if anyone knows how to differentiate (at this age) between a Boat-tailed Grackle (Quiscalus major) and a Common Grackle (Quiscalus quiscula)? It will be fun to see what it grows into. Here are some pics. BTW, I have done this before, but only with raptors. Hopefully the grackle is as hardy, they certainly do seem to be!