Rock-pooling

The low tide reveals a series of rock pools, rich in marine creatures cut off from their wider domain for a few brief hours. Such pools provided a happy hunting ground when I was child; armed with a net and a small, castle-shaped bucket I would push aside seaweed and turn over stones with keen anticipation. These days my rock-pooling is more measured and my knowledge of the creatures revealed better developed. I can now put names to the things that I find, extending identifications from beyond the simple childhood categories of ‘fish’, ’crab’ and ‘prawn’.

The pools here on Scilly are rich in marine life and more diverse than any I have seen on the mainland. Many of the pools are quite sizeable and provide the depth required to sustain larger creatures. Plate-sized crabs of several different species mix with young mullet and giant gobies, the latter providing a sizeable meal for the grey herons and little egrets that haunt the shoreline.

Beyond the rocks is a shallow sandy bay, exposed at low tide and transformed into a vast ‘puddle’ just a few centimetres deep. Walking through the water disturbs a blur of darting shapes – north Atlantic prawns and sand gobies – that scatter at my footfall. There are hundreds of the bright, orange-brown starfish Luidia ciliaris, each with its seven velvety-textured limbs and frill of long white spines extending along the uneven length arms. At first glance most of these starfish appear to be dead, resting inanimate on the sand, but this is not the case as a few minutes patient watching soon reveals. I do not spend long with the starfish, however, as I have so little time on these islands and there is so much more to discover, as the sense of childhood fascination returns.

The opportunities for rock-pooling have become fewer, not just because I now live an hour from the sea but also because the soft geology of East Anglia provides a less suitable substrate for the formation of these temporary tidal pools. Even so, there are places along the Norfolk coast where a particularly low tide will uncover some happy hunting grounds and the opportunity to seek out some of these fascinating marine creatures.