Underwater Observation

I have been observing a specific behaviour over the last few months in one Seal only. This seal is Noah, a large adult male Grey Seal that currently can be found on the south coast of Cornwall. While he is breathing at the surface recovering from a dive, he is able to turn his head and aim his eyes in to the water. I believe that this allows him to view under the surface of the water. He will do this every 10 seconds or so and he will flick his eyes from this downward position back to the surface to view the two sides of the water surface in turn. 

The image above shows this particular seal viewing underwater with his head still at the surface. I believe that this behaviour is performed so that they remain aware of there surroundings and they are reducing any risk of danger.