Walk from Sumburgh to Fitful Head through Quendale and back

I decided to have a walk from Sumburgh Hotel to Fitful Head, which is one of the highest points at the extreme South of Shetland. First I passed through the Airport's Runway, after that through village called Toab, then walked along the Quendale beach, which is Natural reserve and nice place to be seen and after that following the the cliffs I got to the highest point of the Fitful Head. From there after some time walking about the area I got on the main road and returned to Sumburgh. The whole thing too a few hours, but otherwise wasn't difficult at all, just a bit of uneven terrain. At some point on my way back when I was near some seagull-infested place I heard something strange, like a seal call or similar, but different and it is in the video also, but I can't find yet what makes such sounds, so I am open for suggestions.