whelk | Cornish Rock Pools

I used to think I knew my local rocky shores well, but during this last year of lockdowns and staying local, I have been almost nowhere else. What is remarkable, though, is not the intimacy with which I now know every stone and every overhang, or even the way I like to call on some of the long-term inhabitants, but the fact that, despite the familiarity, there are still surprises on every visit.

Photo by Cornish Rock Pools Junior of the beach looking idyllic – looks can be deceptive: it was freezing!

With a brisk northerly wind counteracting any warmth the sun is trying to put out and a strong swell racing in, the conditions are far from ideal. Other Half and Junior start eagerly enough, discovering some light bulb sea squirts on the edge of a boulder, but even before our film maker friend, Greg, joins us, Junior has taken to sitting at the edge of the pool we are exploring in a largely futile attempt to hide from the wind.

Light bulb sea squirts on a rock covered in bryozoans and spirorbis worms.

“You have to look at this,” Junior calls, holding up a large stone he has found. “I think there are piddocks in it.”

We peer into the deep, rounded holes in the stone. In one we can see something retreating into the darkness. There are certainly piddocks in there. These odd bivalve molluscs drill into soft rock, boring out deep holes in which they hide, safe from predators.

Weirdly, piddocks are known to have bioluminescence, glowing blue-green in certain circumstances. The rock also looks as though it has been nibbled at by juvenile piddocks or another rock-boring animal. Air-breathing mites have taken up residence in the holes and bristly chitons cling on to the surface.

Greg arrives to set up, but we’re already feeling the cold and the water is wind-blown and silty from the rough seas. It’s looking far from ideal for capturing the footage of Looe’s amazing marine wildlife that we were hoping for.

Despite our numb fingers we crack on, looking for St Piran’s hermit crabs and fish eggs to film.

We find both, but the crabs are huddled together and hiding in their shells, while the rock goby eggs we find are freshly laid, so aren’t developed yet. In another week or two, hundreds of eyes will gaze out at us, but not today.

While I can still move my frozen fingers a little, I take photos of a young adult sea hare. It is already many times the size of the juveniles I saw here earlier in the year, and is still putting on weight as it chomps through the copious supplies of fresh, new-growth seaweeds.

This sea hare still has some filling out to do, but as though it is keen to prove that it’s already a grown-up, it has laid a tiny patch of its tangled pink spaghetti spawn on the rock.

Sea hare eggs – their spawn looks like pink spaghetti and feels hard to the touch.

The gangly legs of a sea spider catch my eye, flailing about in the seaweed. Ungainly and fragile, it emerges and sways past. A clutch of orange eggs held under its abdomen.

The orange mass under the sea spider’s abdomen is the clutch of eggs.

By now the enjoyment we are getting from encountering creatures is fully counterbalanced by the discomfort of being freezing. I am getting the shivers and it is painful to hold my camera in the icy water, but these big spring tides only come a few times a year so we have to try to make the most.

Heading for the lower shore while we can, we slip and slide on the seaweed that covers every rock. We find a pair of small clingfish but they slip away into the weed before Greg can get in position, performing graceful dives off the rock, heads up, backs arched, like parachutists in freefall. They are so well camouflaged in the pool that we stand no chance of finding them again.

I only see this little clingfish for a few seconds before it dives off the rock.

In the nearby pools I find green shore urchins, chitons and hydroids. This area is rarely out of the water, so is rich and stable with a diverse array of marine life. Some of the nearby rocks are often targeted by people equipped with spikes foraging mainly for crustaceans. The foragers often leave a trail of destruction: stones and seaweed are tossed aside as they go, their metal tools scrape and damage the soft-bodied animals that live on the rocks and if they find any large animals, they take them home to eat.

Green shore urchin with tube feet extended. Animals like these are easily damaged or lose their safe hideaways if poeple move their rocks.

Like other conservationists, I put a lot of energy into studying the ecology of my local patch and into teaching others to love and care for our wildlife. It breaks my heart to see others entering the environment only to destroy it with little regard to sustainability. With the rise of videos promoting taking wild animals from the shore, I find myself having to be increasingly careful not to share any images of commercial species in case it leads to them being targeted. Foraging may have a lower impact on the marine environment than trawling and industrial fishing and has always happened to some degree, but the number of foragers is growing and the impact is not negligible.

There are many soft-bodied animals on the shore, like this daisy anemone with its beautiful purple mouth.

Although people are only officially allowed to remove certain species of crustaceans above a minimum size, this is not enforced by anyone and it seems there are no controls on foraging for ‘personal consumption’, even in a Marine Conservation Zone. These sheltered intertidal pools are an important nursery for young crabs, so minimising disturbance here is important to maintain stocks, as well as for the rest of the ecosystem.

Today I’m relieved to see no sign of foragers. The uncomfortably cold weather is keeping people away, keeping the animals safe. The thought warms me a little.

This ‘White-ruffed’ Aeolidiella alderi sea slug had recently eaten a daisy anemone and taken on the anemone’s colours.

Back to the pools and I am excited to find a slender purple whelk on a tuft of red seaweed. This elegant Raphitoma purpurea is the first live one I’ve found on this stretch of rocks. The shell is striking with its criss-cross of sculptured lines and deep red-purple colour, marked here and there with splashes of white.

The snail has fully extended with its purple-spotted proboscis and is exploring the pool, its dark eyes contrasting starkly with its pearly white body. I spend as long as I can quietly watching it gliding along, feeling its way.

Purple whelk, Raphitoma purpurea, exploring the pool with its fabulous proboscis.

Despite the cold, the wind and the shivers, the day is far from wasted and this is just the start of a week of super-low tides. Once again, the beach has offered up something new.