Common for this time of year, jellyfish brought in by the tides, some finishing their life cycle, are drawn to the bottom of the sea and the fish life in the jellyfish remain until the remains are eaten by other predators and they have to find a new home.
I have used Macro in this shot to high-light the fish within the jellyfish and the jellyfish itself is split-screened below to show how the jellyfish is caught on the sea bed.