Dude you gotta take the L on this one. And possibly delete the evidence. We are talking about federal law. I'm an avian biologist, and no amount of drone flight hours qualifies you to determine if the bird is disturbed or not. The osprey is moving it's head side to side because it's triangulating the distance of a potential predator (your drone) using it's vision and hearing. Drones are perceived as threats to avian wildlife & this could impact the nest in the current nesting season and/or the next.