Bluefin gurnards are unassuming little fish that can move incredibly fast. They look quite drab, and are well camouflaged on the sand, until they spread their pectoral fins, which look like butterfly wings! In some parts of the world this family of fishes is called searobins, because of their resemblance to underwater birds.
They feed mainly on crustaceans (such as small crabs) that they find in and on the sand. If you get an opportunity to watch one on the sand you’ll notice that their beneath their pectoral fins are several rays, which they use almost like little legs as they move along the sand. They are actually not used for ambulation, but to stir up food.
Relatives of this little fish are found all the way up the South African coast to Sodwana and beyond, with variations in colouration. I’ve never heard one, but apparently these fishes use their swim bladders to produce a croaking noise. The angling books I have mention this, and if it’s only a noise they make when they’re caught, then I’m glad not to have heard it.
