Some records in the US (and possibly Canada) are marked as Introduced and others not. Presumably this is based on evidence that the species was introduced into parts of central Mexico during historical times by the Aztecs and then subsequently underwent range expansions northward in more recent times, so the species might be interpreted as Introduced in the US (although that seems a bit of a stretch to me). But this status seems to be inconsistently used. As far as I know, we consider it a native species in the Southwest US.
Reading the comments on the most recent flag, it sounds like these are mistaken. (The Hawaiian one is questionable – the claim in the comments is that the birds there arrived as vagrants, but I don’t know how we’d distinguish between escaped cage birds, natural vagrants, or ship or plane assisted birds.) It also looks like we’ve got someone who’s insisting on the Introduced tag, without comments.
iNat has 25 Canadian records for Great-tailed Grackle and so far as I can tell the system is not flagging the species as Introduced for Canadian locations. Great-tailed is on the South and Central review lists of the Ontario Bird Records Committee.
Yeah, it seems there are a bunch of locations within the US where it has been marked as Introduced, but there are many other locations across NoAm (even some adjacent to the “Introduced” locations) where it isn’t.
I fixed the handful of state-level issues here, but there are a whole heap of smaller geographic locations (counties, locales, etc.) that were set to introduced and it’s quite tedious to fix them all individually. It looks like most of them have none or few iNat records of this species, so it’s not skewing any outputs in a dramatic way at this point.
To be clear, all those “Introduced” locations seem to be incorrect. I’m not aware of introduced populations of Great-tailed Grackle anywhere in the western hemisphere.
Great-tailed grackles are very near and dear to me personally. I remember uploading one of my first observations, thinking to myself “I wonder what kind of crow the nature people think this is?” I thought all black birds who make funny sounds had to be crows. I’ve learned in the past few months, largely from just using iNat, a lot more about birds and all wildlife.
I’ve read some books about them specific to Nevada. I believe they weren’t seen around many parts of Nevada until the 20th century. If memory serves me right, this goes for other areas of the American Southwest as well.
My take on this is that in spite of the introduction of the bird in Tenochtitlan, it was still native to the Mexican region. It may have spread naturally - certainly the more northerly birds have - but the Mexica sped up the process. I don’t know the bird at all, but it certainly does not seem introduced in the way that Starlings were.