My opinion, more no-till farming with waste grain left on the ground and not burned off/tilled in is the main culprit. The milder winters we've had have not helped, but everything used to be a food wasteland after the harvest and field prep afterwards that forced the birds to have to move south. Combine that with the milder winters and not enough snow/ice north of the lake, and the birds simply do not have to go anywhere, and after the northern seasons close, there is no pressure on them to give them a reason to go anywhere. There seems to be more pressure around everywhere, so when birds do decide to move, it is predominantly at night.
