once you watch that, and transplant that to the location and camera angle, and sun above and behind both, dont think theres much doubt, the flat spots in the crop [windblown] has the most rodents using them, as the seed heads are on the ground.
Plus the very windy conditions meant it could hold station and listen, they hunt by sound as much as eyesight, the bird in the vid above is working that patch listening on a windless day, yet can still fly very slow at times, the guys who enter the top of the field spook it, they aint in the vid at the start, they walk down into the circle as he films his UFOs that they spook..
a couple of other things, the greening effect is just that, it says he filmed them 29july.
so it was spring sown wheat, winter sown barley or wheat is yellow and dry by august and mostly combined, that crop was immature and had another 4 weeks in it, so it was spring wheat, he was filming in a eastly direction, with a westerly wind, the sun was behind and low, with a typical summer evening glow behind him imo, it was filmed between 7pm and 9pm, for the sun to be in that position, at that time of year, quite simply it made the bird stick out like a stallions cock.
Could be a camera effect aswell
that crop could be winter wheat and yellow, yet the camera has darkened it, and picked up the yellow reflected sunlight of the off white plummage, and made it stand out more than it actually did, if everything was its proper shade, if ya folla.
and the reason the pair were out together that early, which is common, is that they would of had upto 6 chicks to feed, thats why when he missed he was straight up in the air again and over another patch, theres so much prey about, not like the winter bird who tried longer to feret out the voles from the winter undergrowth in the video above as food is scarce.
heres one hunting on sound only.
[not a barn owl granted, but no difference