Those birds left CO for the South - probably don't normally get that in the middle of summer.
There's very little smoke in NM. Some but not enough to kill the birds or cause them to fly a billion miles. That was the summer cold snap that did it.
This is a classic case of not enough Ornithological Meteorologists or Meteorological Ornithologists. Or maybe because the Ornithological convention and Meteorological convention (which are normally hosted in the same hotel in September) were both cancelled this year due to Covid-19. (this last paragraph was a failed attempt at humor)