Indeed. I had to abandon a flight in early May this year. The reason? Migrating birds, hundreds of the little blighters flying up the coast and across Cardigan Bay. Just too risky....Good man. There's a misconception among some pilot's that uas' can't go to negative heights and if they do that they will become unpredictable. This is not the case. I fly my H480 and my Phantom below zero altitude quite regularly with no problems.
Yes, Ashworth Moor Reservoir. The ruins in the video are Cheesden Mill in the Cheesden Valley. You can get to the ruins by going down a public footpath opposite and just down the road a bit from Owd Betts pub. Walk along the path for a couple of hundred yards. It's less than half a hour's drive away from my abode. For the footage in the above video I took off from the hill overlooking the ruins just to the West of the ***.
I like to do coastal stuff too and, being the lazy person I am, often fly from cliffs. You gotta watch out for the birds, though. They can get a bit territorial so avoid taking off from cliffs during nesting season.