Tide Pool Creatures to Spot on Rocky Shores

Why the Rocky Shore Rewards Slow Looking

There is a particular kind of quiet that arrives about ten minutes into a rockpool. You have stopped talking, your shoulders have dropped, and you are crouched so still that a blenny has decided you are part of the landscape. For anyone who swims in UK seas, the rocky shore is the perfect companion to a cold dip: the swim wakes you up, and the pool calms you back down. Both happen on the same stretch of coast, and the second one costs nothing and requires no wetsuit.

It also happens to be one of the best wildlife experiences in Britain. You do not need a boat, a guide or a reserve. A single good pool on a spring tide can hold twenty species. The trick is knowing where to look, and how to behave once you find something.

Reading the Shore in Zones

Life on a rocky shore is arranged in bands, because different animals can tolerate different amounts of time out of water. Learn the bands and you can predict what you will find before you kneel down.

• Upper shore — the splash zone, dry for most of the day. Look for limpets clamped to the rock, barnacles like tiny volcanoes, periwinkles in crevices and the occasional chiton, a flat armoured creature the colour of wet slate.
• Middle shore — exposed only at low water. This is the best zone for beadlet anemones, dog whelks, mussels, top shells and small shore crabs tucked under weed.
• Lower shore — uncovered for perhaps an hour at a really low spring tide. Here you get the prizes: snakelocks anemones with their green tentacles, common starfish, brittlestars, edible crabs and, on western coasts, sea urchins.

Timing matters as much as place. Spring tides — the biggest range, around the new and full moon — expose the lower shore. Neap tides barely touch it. Tides also run roughly fifty minutes later each day, so a good low water this week may be a poor one next week.

Anemones, Limpets, Crabs and Starfish

Start with anemones, because they are forgiving and unmistakable. A beadlet anemone looks like a blob of red or green jam when it is out of water; give it a few minutes in a pool and it opens into a ring of tentacles. Look for the blue beads around the base of the red ones — those are special stinging cells. Snakelocks anemones are green with purple-tipped tentacles and do not retract, so you will often spot them before anything else.

Limpets are worth more than a glance. Each one grinds its own resting spot, known as a home scar, and returns to it after grazing. If you prise one off, it will struggle to find that exact fit again and may dry out. Do not do it.

Crabs are the easy crowd-pleaser. Shore crabs are green-brown and about the size of a two-pound coin; velvet swimming crabs are smaller, blue-tinged and famously bad-tempered, raising both front claws at you. Edible crabs sit in deeper gullies. Always check under ledges and among weed, but lift gently and let them scuttle.

Starfish are less common than people expect, and never in every pool. Common starfish prefer the lower shore and feed on mussels, prising them open with their arms. If you find one, watch it right itself on the bottom of a shallow tray — it takes a minute or two and is worth the wait.

Wet Your Hands and Handle Very Little

Handling is where well-meaning visitors go wrong. Anemones, fish and shellfish are coated in a layer of mucus that protects them from drying out and from infection. Dry hands and suncream strip it away. So:

• Wet your hands in seawater before you touch anything.
• Never wear suncream on your hands while rockpooling — rinse them first.
• Use a flat, open palm rather than fingertips, and never squeeze.
• Keep a shallow white tray of seawater for a few minutes of viewing, then pour everything back exactly where it came from.
• Leave anything attached to the rock alone. Limpets, barnacles and mussels are glued on for good reason.

Kneel on wet weed rather than dry, and watch where your boots land — a patch of barnacles is a hundred animals.

Put Every Stone Back Exactly as You Found It

This is the rule that matters more than any other. A stone on a rocky shore is a roof. Underneath it is cool, dark and damp, and the creatures living there are adapted to that and nothing else. Turn a stone over and leave it that way, and everything beneath it bakes or gets picked off within hours.

So when you turn a stone, put it back the same way up, settled into the same hollow, with any weed still attached facing the light. If a stone is too big to replace easily, leave it alone. If you knock a limpet loose by accident, accept that it was a mistake and move on more carefully.

Tides, Timing and Staying Safe

Check a tide table before you go, and check it again on the day itself — an offshore wind and low pressure can push water further out, or bring it back faster than predicted. On a shallow shore, a spring tide can move several metres in an hour.

A few habits keep it safe and pleasant. Tell someone where you are going and when you will be back. Never turn your back on the sea for long, and keep an eye on the swell along exposed ledges. Wear boots with grip rather than flip-flops, and take a warm layer — rockpooling after a swim is lovely, but you cool down fast once you stop moving. Go in autumn, winter or early spring, when the big low tides fall in daylight: the shore is quiet, the water is clear, and you will have the pools to yourself.