Found under a stone on a seaweed covered part of the muddy shore as the low tide was coming back in.
No interactions present.
A very interesting fish ktmartin, Im familiar with the name but not the animal. Fairly distinctive and it looks good for the species. It looks like a fish which would be tricky to catch if in water, as per rockling, extremely evasive.
I didn't know this fish either so I looked at the pictures in a book ( Hayward, P.J & Ryland, J.S. Handbook of the marine fauna of North-west Europe. 1995 ( and several later reprints), OUP.)
Zoarces viviparus looks a distinct possibility. There are 2posts on iSpot, so have a look & see what you think.
It is good practice to check other authoritative references too, perhaps MaRLIN & http://www.marlin.ac.uk/species/detail/2229
and Marine Portal. http://species-identification.org/species.php?species_group=fnam&id=1704...
I am agreeing.
Lat/Lng: 57.4941, -4.2477
OS grid ref: NH653471
On the shore at low tide.