Belly down on the grey-tan sand of a south Devon beach, I am turning out sandcastle after sandcastle from a green bucket with a starfish on it, when I notice that the sand is seething with life. “Grasshopper!” my almost-two-year-old daughter exclaims, and she’s half right. The creatures flicking away from my feet, and from the ruins of the sand turret she has taken such pleasure in demolishing, are in fact not insects, but sand hoppers (Talitrus saltator).
I scoop one of the housefly-sized crustaceans on to the palm of my hand, and bring it to eye level. Now we are close enough to see the animal’s glistening exoskeleton, its shrimp-like legs, its body the colour of every grain of sand on the beach. For a few seconds the sand hopper lies there, motionless, like a dog half-curled by the fire. Then, with no perceptible movement at all, it vanishes, in a kinetic movement too quick for the human eye.
