I watched the video and discovered that at 0.05 into the clip, you can see another, seemingly identical UAP meeting up with the first one and making an extremely swift bow to change direction and disappear from sight when the camera pans downwards and to the left. A very advanced manoeuvre if it was an aircraft of any kind.
But also a very common behaviour in birds. So I think this is a bird (or rather, two birds), and while I'm no expert, the movement of the second UAP makes me think it isn't even a particularly large bird we are dealing with, since it's a behaviour I associate mostly with small to medium sized birds with good manoeuvrability. So if it's a bird I'm thinking it's a large gull at most, size-wise. And I think it's a bird.