Are you worried about crows attacking then drone? Do they?
A single crow most likely won't, but if it is a large group of them (a murder), there is a good chance they will. I have had it happen many times in the industrial area where I live. They are very smart and know what they are doing when it comes to an unknown object they do not want around.Dunno if they do actively go after drones. My worry is the number of them that I saw on Tuesday and the likelihood of disturbing them or suffering a bird strike because of the number of birds. Think Hitchcock's 'The Birds'. Ok, I'm exaggerating a bit there, but there were quite a few flying to and from the tower. I suspect, though, that the number of them was linked to the time of day I was there since I've noticed that at other times there are non to be seen. That is why I didn't decline the job there and then opting to monitor the situation for a week to determine the best time of day for the operation. The client (a man of God you might say) is happy for me to delay the operation while I monitor the situation.
What I have observed with them is this. Usually when you become of interest to them one will fly near you to see what you are. Within a few moments of that, others will fly away but only to come back at a you from a different approach, kinda like they are going to flank you.
My only solution to this so far is to fly your UAV away from them and very fast, because when they start to circle, you are kinda screwed. The crows group together and circle to look as though they are one large object......intimidation factor. You can't force your way through them as that is a huge no no.
Anytime they are around, I have a couple of spotters watching them because they are so sneaky and fast. When they decide to come at you, it's very quick how they get organised. A few times they were so close that all the video caught was complete black in the field of view.
It's kinda surreal when it happens, but I honestly don't know what a guy can do. Perhaps an Airsoft pistol to keep them away?.....it's non-lethal, but not sure what the rules for Airsoft are where you live. Remember they are smart, so if they find that every time they go towards your UAV they get a little spank from the Airsoft plastic bb, there is a good chance they will learn not to go after it.....at least that group of them.