They like to chase the tractor at certain times of the week. Since BIL has basically claimed it as his vehicle, the delivery schedule is a little spotty, but they do this every Friday and usually Tuesday or Wednesday when they see the tractor. One will follow it, and if the tractor goes anywhere near The abattoir, suddenly the numbers grow. Ravens aren’t nearly as social as crows, usually hanging out in pairs or small family groups, but will band together in an “Unkindness” like this for special occasions… like Friday, or whenever BIL gets around to emptying the trim bins from the meat cutting days, and for running off Eagles during nesting season. The eagles and Vultures usually just hang out at the pit and wait.