It was quite warm where this crow was foraging. The beak open to facilitate cooling.
I experimented with a minimal hide, which is basically a camouflage net hung over the scope and tripod. It seemed to work really well, as this crow came quite close. The wheatear, which was my target, suddenly landed at a distance of 4 meters, to close to focus on!
I can move the hide around slowly, remaining hidden and not upsetting the wildlife. More experiments will follow.