All posts by Heather Buttivant

Meeting up and staying apart in the rock pools

When I’m sitting here writing my blog in the evening, with the cat snoring gently beside me, I find it hard to imagine that people anywhere in the world might be reading about my finds the next day. So, it’s always lovely to receive messages from people who follow the blog and share my passion for our rock pool wildlife. It’s especially surprising to me that these include many people I’ve never met and that some of my readers even live beyond the Tamar!

With the days beginning to draw in and with all normal group activities off due to Covid, making connections with others is more important than ever. When I heard from a couple of keen naturalists and Shoresearchers planning a trip to Cornwall, I thought it could be fun to head out on the shore together with my family. I couldn’t have been more right!

You know someone is a good person when they like finding slugs. Within minutes of meeting our new friends on Millendreath beach near Looe, we had established that slugs were top of their wishlist of things to find. I led the way to “slug alley”, a deep gully between the rocks where I often find sea slugs feeding on the sponges, squirts, bryozoans and hydroids that line the dripping overhangs.

We advance in our family groups, keeping several metres apart, pointing at interesting creatures, giving directions then backing away. By this stage in the pandemic, we’re all confident in these new dance steps.

Botryllus leachii colonial sea squirts

Large patches of colonial sea squirts smooth over the rocky surfaces, providing not just striking colours and patterns but food for many animals that predate them. We find both the European three-spot cowrie and the Arctic cowrie happily gorging themselves on this beautiful feast.

A cowrie on the search for sea squirts to eat.

A brown spot among the squirts and barnacles catches my eye. Although the colours blend in perfectly, it looks different from its surrounds. I gently touch it and it comes away. In a seawater-filled petri dish it rapidly transforms itself, puffing up, elongating and sprouting feathery gills and tall rhinophores. There’s no doubt about it, we have our first slug. My excitement is as great as that of our new friends – this is a species I have never seen before.

Goniodoris castanea exploring the petri dish.

We take turns to examine the slug and take photos. As soon as it is under my camera, which shows far more detail than I can make out with the naked eye, I recognise it from my books (yes, I browse slug books for fun). It’s my first Goniodoris castanea. Castanea means chestnut and the slug’s autumnal mottling of red, brown and white hues make seems a perfect fit with the oncoming season.

Goniodoris castanea showing off its beautiful autumnal colours.
Goniodoris castanea

While our friends marvel at the slug, Junior makes another exciting find. He knows what it is just by the purplish tips of the arms protruding from under the rock. “Spiny starfish!” he calls. We carefully move it out to take a look and it’s a monster. Our starfish has clearly found plenty to eat in this area. Although we regularly see them on the shore here, spiny starfish aren’t found in rockpools in some other parts of the country and this is another new species for our visitors.

I forgot to take photos of the spiny starfish due to my excitement over the slugs – but here’s a pic of one we found on an earlier expedition to Millendreath.

We edge ever outwards with the tide. Although we can hear the shouts of holidaymakers playing in the waves on the beach beyond the rocks, no one else ventures into our magical gully where startled sand eels zip across the surface of the water like skimming stones and velvet swimming crabs scuttle across the seabed then bury themselves in the sand, leaving only their red eyes visible.

A lurking velvet swimming crab.

Some of the rocks are fringed with a dense covering of brown seaweeds. Toothed wrack and kelp compete for space here and clinging to this forest, mossy bryozoans and delicate hydroids thrive, creating a perfect habitat for isopods and slugs. Some of the seaweeds have crescents of white jelly scattered among their fronds. These are sea slug eggs but it takes me some time to find the slug itself, which is smaller than its spawn and decorated with bright yellow and black which somehow make it hard to see.

Sea slug spawn…. now to find the slugs.

These pretty little slugs were, until very recently, known as Polycera quadrilineata. Scientists have now discovered that there are two separate species and the ones we see here, which sometimes have black lines and spots, are now called Polycera norvegica.

Polycera norvegica feeding on bryozoans.

In the moving seaweed, it’s hard to take clear photos and the tide is, of course, coming in just as I’m trying to position the camera in water that’s already waist deep, but we are all content just to be here, together but apart, sharing this experience of encountering incredible creatures.

Polycera norvegica.
Pair of Polycera norvegica sea slugs with the edge of a fingernail in shot showing just how tiny these stunning little creatures are!

These are strange times for everyone, but finding ways to come together and enjoy nature is what makes the world go round (for me at least). Thanks to our new friends for making it a fabulous day. Happy rock pooling!

This time of year, the kelp is studded with blue-rayed limpets – always a joy to see.
Brown sea cucumber – Aslia lefevrei.

Introducing the Rock Pool Project and the ‘Rocket Jelly’

After a whirlwind of book promotion, including my debut on Woman’s Hour, in which I introduced the nation to barnacle reproduction, it was a relief to return to the rock pools. Thursday was the sort of mizzly day that only sea creatures and marine life fanatics appreciate, so I had no doubt that Dr Ben Holt would turn up as planned for some distanced exploration of one of my favourite local rocky shores near Looe.

Who could resist a day out in the drizzle?

Ben may have started his career researching fish in the Caribbean, but he soon realised that Cornwall was the best place in the world and moved to Falmouth, where he founded the fabulous Rock Pool Project.

The Rock Pool Project is a not-for-profit social enterprise, offering not just rockpooling and marine conservation themed activities on Cornish beaches for the public and school children, but also brings the rock pools indoors with the help of its mobile rock pool. So far, the team of experts has visited schools, care homes and community events to give people the chance to learn about our rock pool wildlife and how we can look after it. Now they are looking to expand their range of citizen science projects that everyone can join in, as well as reaching out more widely, once social distancing restrictions allow.

Socially distanced photo with Dr Ben Holt of the Rock Pool Project. (Photo by Cornish Rock Pools Junior).

This month Junior and I helped to test out the crustacean survey method and had great fun seeing how many different species of barnacle, prawn and crab we could find within our allotted time. Anyone will be able to sign up to survey a local beach, regardless of previous knowledge and experience. It’s a great way to get out with the family, learn together and discover your local beach in a new way, and barnacles are lovely if you catch them feeding as the tide’s going out!

Chthamalus sp. barnacles showing a flash of blue as they open to feed.

Back to our rainy day and Ben, Junior and I soon discovered that trying to point out tiny creatures is a challenge when you’re social distancing. I found a stalked jelly but by the time I’d moved a few metres away, the seaweed had shifted and it took a while for Ben to relocate it. Despite the challenges, we made the most of having the beach to ourselves.

One of the largest Haliclystus octoradiatus stalked jellyfish we found.

The dense seaweed made it hard to see into the water, but we found crabs, urchins and ascidians as we clambered ever further out across the rocks. We had a half-mile long stretch of beach all to ourselves and everything had fallen silent under the misty cloud.

Star ascidian colonial sea squirt on an overhang.
Arctic cowrie looking for sea squirts to eat, its shell almost entirely covered by its mantle.

Junior discovered a clump of seaweed with lots of stalked jellies on it: Halyclistus octoradiatus and Calvadosia campanulata. Most were too small to photograph in the moving water, but we delighted in losing and re-finding them among the swirling weed.

Calvadosia campanulata stalked jellyfish.

As the tide moved in, Ben was intent on finding a stalked jellyfish for himself. After a few minutes of filming the stunningly pink entrance to a worm burrow that Junior had found, I joined Ben’s search.

With the tide rising up my boots I was about to give up on the stalked jellies, when I saw a tiny shape float past me. It looked like a stalked jellyfish that had become detached from the seaweed, drifing with the tide. I made a quick grab and scooped it into a bucket.

The whole animal was only a few millimetres long and for a moment I wondered if it was just a blob of seaweed. Junior and I peered into the bucket, heads touching. The blob had arms but wasn’t a stalked jelly. It looked more like a miniature space rocket pointed skyward, with trailing tentacles spread around its base. As we watched it launched, zipping across the bucket at surprising speed.

The tiny jelly was tricky to photograph and kept zooming away across the petri dish.

Under my camera it was weirder than ever. The rocket shape was enclosed in a jelly dome and the tentacles had a knobbly appearance, rather like the sucker arms of an octopus. At the base of each tentacle was a black spot: a primitive eye. This was a jellyfish-like medusa of an athecate hydroid, Cladonema radiatum, a species I’ve only seen once before. We decided to call it the rocket jelly, although I’ve also heard it called the root-arm jelly, presumably due to those twisting tentacles. Although it isn’t a true jellyfish, the tentacles do pack a fair sting.

Cladonema radiatum – the ‘rocket jelly’. An athecate hydroid medusa.

 We took turns watching and trying to photograph the minute animal as it zipped around a petri dish. The tide was rising steadily so after a few minutes, Junior waded out and released the medusa, repeating the process several times as it kept swimming back to the petri dish.

Cladonema radiatus swimming upside-down for a moment.
Cladonema radiatum showing the dark eye spots at the base of the tentacle arms.

It may be a while before we are able to resume events and before I can meet again with Ben and his team, but lots is going on behind the scenes both at The Rock Pool Project and at Cornish Rock Pools HQ where the first draft of my new children’s activity book is nearing completion. Watch this space!

Junior’s pink worm burrow.

Summer is acome unto day… May Rock Pool Gallery

Summer arrives early in Cornwall, with festivals around the county singing in the new season on the first of May every year.  Except, this year the Padstow Obby Osses have stayed in their stables, the Calstock Giant hasn’t set sail down the Tamar to re-join his love, and there has been none of the usual dancing through the streets of Helston.

Oblivious to all of this, the natural world is carrying on. Swifts are screaming past the window,  the herring gulls are nestled on their mossy rooftop nests and in rockpools everywhere, there will be tangles of new-growing seaweed, father fish guarding their eggs and all manner of colourful creatures going about their usual business.

Scroll through the gallery below for a glimpse of what will be happening right now beneath the waves in rock pools around Cornwall. And if you’d like to find out more about our amazing marine life, explore my blog, or take a look at the fantastic video workshops that Cornwall Wildlife Trust has been busy creating. Happy virtual rockpooling!

  • Our brown Geitodoris planata and its much paler yellow mate getting friendly in the Cornish rock pools!
  • This small species of spider crab (Inachus sp.) was so completely covered in sponges that I couldn't see her shell at all.
  • Another species of stalked jellyfish - Haliclystus octoradiatus - near Penzance
  • Facelina auriculata sea slug
  • Polycera quadrilineata sea slug at Gyllingvase, Falmouth

Bottoms-up! Wildlife Recording on the Last Spring Tides Before Lockdown

There’s no collective noun, as far as I am aware, for a group of rock poolers, but if there was it would refer to bottoms in the air as that’s our standard position – head down, bottom up, searching for marine life. On the best tides it’s not unusual to find other rock pool fanatics on my local shore, drawn by the promise of rarely accessible habitats. So, during the spring tides of early March, I found myself in the company of the bottoms-up brigade at Hannafore, exploring one of our favourite shores.

Junior and his friends were with me, enjoying one of the endless field trips that usually make up our home educating life. Around us, life was churning along as usual despite the first Coronavirus cases being recorded in Cornwall a day or two before. With so many of good friends living elsewhere in Europe, we were only too aware of how quickly the situation might deteriorate, but while we were already starting to avoid indoor events and gatherings as far as we could, the open shore felt as good a place to be as any.

A beautifully marked Xantho pillipes crab – one of many lovely finds at Hannafore.

While the kids were building stone citadels and warring rocky villages at the top of the beach, I gave them vague instructions to come and find me soon and set off down the shore, following the receding tide over slippery rocks and frothing seaweed. I was joined by a friend from north Devon making a special guest appearance at Hannafore.

Among the boulders we discovered a tiny Montagu’s sea snail; a small tadpole-like fish with tiny eyes that tends to curl its tail round its head, looking more like a sleeping cat to me than a snail. These fish were soon turning up everywhere, with more than half-a dozen down a single gully.

A Montagu’s sea snail (fish) in its classic curled-up position. The fish suckers onto rocks.

Further along, a topknot flatfish was clinging to the rock with its sucker-fin, so perfectly blended with the colours of the stones and weed that only its fluttering gills and swivelling eyes gave it away.

Topknots sucker onto rocks and stay still to avoid being seen. Like many other intertidal fish, they can change colour to match their surroundings.

A head popped up from a neighbouring gully, another marine biologist friend from the Marine Biological Association  (MBA) was busy exploring, and across the lagoon, other friends from Bude Marine Group were approaching. Junior and his friends also abandoned their construction works and set out to explore the exposed reef armed with cameras to capture their adventures.

A dahlia anemone. These anemones have a sticky column and are often covered in gravel.

Despite a brisk, cold wind that was welding my fingers to my camera, the excitement of the finds stopped me from worrying about anything except what was in front of me. Sea slugs, quirky hydroids, and beautiful clingfish kept me occupied and there was still a little time before the tide would turn.

A small clingfish, possibly a two-spot. These fish also have a sucker to help them stick to rocks.

The egg cases of the larger of our two catshark species were plentiful on the rainbow wrack and a shout from my MBA friend brought the children running back – a newly-hatched baby Greater spotted catshark (Scyliorhinus stellaris).

Greater spotted catshark egg cases, often called mermaid’s purses.

Baby Greater spotted cat shark (Scyliorhinus stellaris).

Time always feels desperately short to explore this fabulous environment, but every second is full of wonder. Finding a hairy hermit crab made my day, if it wasn’t already made by just being there with so many fantastic and knowledgeable people.

Hairy hermit crab. It’s easy to see how it gets its name!

The hairy hermit crab isn’t a common find on our local shores and this particular crab was exceptionally co-operative, emerging from its hiding place without hesitation which meant I could take photos and video of its incredibly hairy claws, its pale blue eyes and its stunning violet antennae.

Hairy hermit crab.

This week I published the paperback of my book and shared the celebrations through video interviews and a recorded book reading.

Like all children, my son is doing his best to adapt to keeping in touch with friends and family from a distance and my other half is working from home. Some friends have been desperately ill and others still are putting their lives on the line every day as nurses and critical workers. Writing has felt pointless at times, impossible at other time and yet it seems important to share the beautiful things, because these will return.

Stalked jellyfish, Calvadosia cruxmelitensis.

The happy moments shared with my bottoms-up brigade of rock poolers, the exploration and the freedom may just be a memory at the moment, but I am reassured to know that life carries out there beneath the waves as it will here above. The wild creatures that make me catch my breath will still be there when all this is over. Friendships remain and my little community is showing strength, compassion and ingenuity to make sure we carry each other through.

European 3-spot cowrie (Trivia monacha) on star ascidian (Botryllus schlosseri).

Stay safe and watch this space for more colourful creatures to brighten your days, whatever they may bring.

Spot the spider crab! (Macropodia sp.)
Spider crab (Macropodia sp.)
A well-decorated spider crab (Macropodia sp.) in the water. This crab deliberately covers itself in seaweed as camouflage.
Aeolidia filomena – The great grey sea slug or ‘sheep’ slug. These common sea slugs feed on sea anemones.

A Rainbow in the Cornish Rock Pools – Andrà tutto bene!

In these strange and frightening times, I could not be more proud of the strength and courage I am seeing in my friends and the local community. Our world has changed, seemingly overnight, yet in Cornwall, as elsewhere, people are meeting the challenges head-on.

While many people are risking their lives every day to look after others and deliver vital services, I can do little to help except support elderly neighbours and avoid contact. However, as long as a daily family walk from our home to our local shore is safe and permitted, I hope that I can lift someone’s mood by sharing what we see.

It feels like a dream to step into nature, to experience how life carries on in all its colour, beauty and chaos when human lives are narrowing to the confines of four walls. The clear blue skies, arriving at last after months of storms, open out the horizon and lighten the sea, while the glittering reflection of the sun shines out of every pool.

I feel like I could fish the sun out of this pool. A welcome change after a wet and stormy winter.

New seaweeds are suddenly sprouting, reaching up through the clear water, among dense tufts of the pink coral weed that lines these pools all through the year. A little shanny watches me from its hiding place deep in the water, cradled by rocks on either side.

The shanny – also known as the common blenny – has lovely eyes.

As I try to photograph the fish’s bright clown-eyes, Junior spots another creature clinging to the weed. We kneel at the edge of the water, our heads touching as he points it out. His find is a slender woodlouse-like creature speckled with white spots, an isopod crustacean called Idotea balthica.

Idotea balthica – an isopod crustacean.

In a dark gully cut between the rocks by the water that rushes out between the tides, I see a flash of colour. For days now, I have been capturing images of spring flowers, breaking waves and open seascapes to send to a dear friend on lockdown with her partner and cat in her flat in Bergamo, Italy. As soon as I see this strawberry anemone, I know she will love it.

It is one of the few unexpected positive effects of the enforced confinement that we are finding time to reach out and renew friendships. Now, she and I are sharing videos and inspiration daily, carrying each other through. She has turned her substantial abilities to creating stories and artwork to reassure those struggling with fear.

Among other things, she has shared heartwarming images of paintings and balcony decorations depicting rainbows, the symbol of hope. The slogan of the community in Italy has become ‘Andrà tutto bene!” – Everything will be all right.

The tide is turning and the anemone sways with the current, disappearing under seaweed and re-emerging again, in constant motion that makes photography difficult. I balance myself on a rock to stop the waves flooding my wellies and wait for an instant of stillness. The slant of the sun’s rays through the water makes the camera screen white-out. I take some snaps and hope for the best.

I check my images when I get home and the strawberry anemone has come out as I hoped, its warm colour and flower-like tentacles are as lovely as I remember.

It is only when I download the images onto my larger laptop screen that I notice the rainbows playing on the pink paint weed under the anemone. Rainbows of hope for my friend in Italy and for all those facing horrors and hardships. Rainbows for all of us wondering where this will end.

Strawberry anemone on pink paint weed surrounded by little ‘rainbows’.

All will be well.

In the coming weeks and months, I hope to bring you more beauty from the Cornish rock pools. Even if we become completely locked down, I have a treasure trove of photos to go through so watch this space.

More photos from my last rock pool walk below.

Snakelocks anemone
Painted top shell
A great grey sea slug. The iridescent blue lines in the foreground near its head are a fragment of blue-rayed limpet shell. Another unexpected little rainbow in the rock pool!
Great grey sea slug. The white tubes on the rocks are made by keel worms. You can see a keel worm’s circle of feathery feeding tentacles to the left of the slug.
Broad-clawed porcelain crab.

What to do when Rock pooling is cancelled? Go anyway!

After weeks of storms, the Looe Marine Conservation Group was hoping for a break in the weather for their half-term family rock pool ramble. Unfortunately the Cornish weather had other plans. With gusty winds delivering pulses of the sort of ‘light’ rain that soaks you in seconds, LMCG did the sensible thing and cancelled.

Meanwhile back at Cornish Rock Pools HQ, Junior already had several jumpers, three sets of socks and full waterproofs on and was ready to set off. Some of his friends were also set to join us on Hannafore beach. So, we ignored the cancellation, put our hoods up and set off.

Scooping up another hardy family on our way down the shore, we picked our way down to some gullies sheltered from the wind by large rocks.

“A fish,” Junior shouted. “I don’t know what it is. It looks like a tadpole.”

I made my way over to where the children were gathered.

“I think it might be a clingfish,” Junior explained.

The small dark blob was certainly suckering onto a stone. It was lying very still with its tapering tail curled around its wide head, hoping that it was well enough camouflaged that we couldn’t see it.

Bizarrely, this little fish is known as a Montagu’s sea snail. It has tiny eyes compared to the size of its head and with its fins tucked tight to its body, it does look rather like a tadpole. Under its belly, the fins have evolved to create a sucker that it can use to hold onto rocks, making it ideally suited to life around the shore.

Montagu’s sea snail (Liparis montagui) – a fish despite the name.

Montagu’s sea snails vary enormously in their patterning but have an unmistakeable shape.

In a nearby rock pool I found a group of young Xantho pilipes crabs sheltering under a boulder. These crabs have dense hairs around their back legs and thick-set claws, but their colour varies a lot. This one caught my eye as it was especially beautiful.

A brightly-patterned Xantho pilipes crab.

Most of the dead-looking crabs we find on the beach are empty moults, left behind by a crab that has grown out of its shell. I could tell straight away that this one had not been so lucky.

Dead Xantho pilipes crab being picked clean by Netted dog whelks.

Netted dog whelks are the vultures of the rocky shore. Equipped with long siphons that look like vacuum cleaner attachments, they spend their lives sifting through the sand and hoovering up any dead creatures. When something large like a crab dies, they can scent the food and quickly home in.

Unpleasant though it looks, scavengers play a vital role in any ecosystem, quickly and efficiently breaking down decaying matter. The children had a fascinating time watching the netted dog whelks at work. They wre moving surprisingly quickly, spinning their shells from side to side as they edged into spaces and were clearly competing to get at the best bits of food.

Before long the children had made lots of other finds. Among the tubs were several hermit crabs that had been given names. Junior adopted a lugworm that he found under a large stone and spent a long time watching and trying to photograph it. These worms make burrows in the sand and have a wide circular mouth that gapes open to swallow sediment, from which they filter out their food.

Lugworm with mouth open – photo by Cornish Rock Pools Junior
Junior’s lugworm

The rain had died down over the course of the morning and no-one was rushing to leave. So, after we had carefully said goodbye to all of the animals that the children had been caring for in their tubs, we took a last look around between the rocks.

As always there were plenty of treasures to be found and before long, the tide was turning and lunch was calling.

Green shore urchin.
Long spined sea scorpion
Bootlace worm – these worms are usually several metres long if fully extended but are always quite tangled!
Pheasant shell
Shore rockling (5 bearded) with a hemit crab and a prawn photobombing in the foreground.
Long-clawed porcelain crab
Another prettily patterned juvenile Xannto pilipes crab.

The Looe Marine Conservation Group run rock pooling events during every school holiday through the year and these are only rarely cancelled. There are similar groups all around Cornwall, and some across the border in Devon too. Look out for events near you!

The Surprising Mini-World of Rock Pool Insects

If my blog posts have seemed a bit thin on the ground the last few months, it’s fair to put the blame on Atiyah, Brendan, Ciara and Dennis.

Even on the good days the lighting and conditions have been less than ideal so, to make the best of a mediocre tide, I enlisted the help of Other Half. Together, we could look under the sort of rock I usually see but leave alone, knowing it weighs far more than I do.

This short video shows you some of the animals living there…. read on to find out more.

Other Half was pleased with the strawberry anemones, which were enormously plump with all their tentacles retracted.

Strawberry anemone
Strawberry anemone

Under a carefully constructed shelter made of small stones and pieces of kelp we could also see the purple-tipped spines of a green shore urchin. Among its many disc-topped tube feet, a long polychaete worm was exploring.

Green shore urchin
Green shore urchin

What drew my eye most, though, were the holes in the rock. These were scattered across the surface of the rock and about the circumference of a pencil. I caught the tiniest glimpse of movement as I looked into one of them.

Piddock holes underneath the boulder.

If I were the BBC Natural History Unit, I’d have filmed inside with an endoscope or transported the rock to deeper water so I could photograph the gaping shells emerging to feed.  Instead, you will have to take my word for it that there were piddocks in those holes!

Piddocks are bivalve molluscs (clam shells), which burrow into the rock and spend their entire lives in their holes.

A rock with this many cracks and holes in it is bound to contain some good hiding places for other animals and also some air pockets, which enable some of our most unlikely rock pool wildlife to survive being submerged twice a day. Some insects and other arthropods that breathe air live here, but you have to be patient to see them.

I settled down with my camera and before long, the first waggling antennae of a springtail poked over the rim.

The end of a piddock protruding from a hole. (Taken on another occasion).

I often see rafts of blue-grey Anurida maritima springtails floating on the surface tension of pools in the summer, but these were smaller still and so pale they looked almost transparent. They are clearly visible in the video but I could only take very blurred still photos.

The fabulous Essential Guide to Rock Pooling by Steve Trewhella and Julie Hatcher was my first port of call in trying to identify them. The book has great photos and plenty of clear information on what to look for. Steve kindly identified these springtails as Axelsonia littorlis – a new species to me. It’s amazing what you find when you stop to look.

The best shots I could get were of a larger bug called Aepophilus bonnairei, a beetle-like creature with red eyes and a spiky coat of hairs around its back and legs. These hairs trap air bubbles, which help the insect to breathe when it is submerged.

Aeopophilus bonnairei bug on a rock
Aepophilus bonnairei bug on a rock
A juvenile Aepophilus bonnarirei.

Time was short as the tide was already turning and the waves were pounding in. I tried to photograph as many species as I could so that I could put records together afterwards. Some, like the painted top shells and the various crabs, are easy to identify.

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Painted top shell.

One of the most striking sponges I see on the shore is the vivid blue Terpios gelatinosus. Many other sponges are harder to identify confidently.

Blue sponge - Terpios gelatinosus with keel worm
Blue sponge – Terpios gelatinosus – with keel worm

It seemed that no part of this valuable habitat was left unoccupied. To avoid any of these creatures coming to harm, we gently manoeuvred the rock back in place well before the surging waves reached us.

Different coloured patches of star ascidian among spirorbid worms, keel worms and other life on the boulder.

As always, I was left in utter awe of the fragile little creatures we saw.

It is remarkable that these animals will cling onto life here no matter how much the wind howls and the sea roars around them, while we head home to bring the plant pots in out of the wind, check the fences and put the kettle on.

Broad-clawed porcelain crab
A grey and windy day on the shore. It’s incredible that anything can survive in these pools, especially insects.

A Quick Winter Walk

Though there is much to love about December, I know I’m not the only one who’s flagging well before the end of the month. The spring tides arrive at the perfect time to boost my energy levels, ready for all the rockpooling and writing adventures that await me in 2020.

No-one in the family is sure what day it is, and the gloomy weather isn’t doing anything for our timekeeping. By the time we reach Plaidy, we only have half an hour left before it will begin to get dark. Fortunately, that’s plenty of time to find some winter colour.

This beach is ideal for strawberry anemones, a species that seems to like some wave energy. While I try to take photos of a stunning open anemone, its bright tentacles tucked too far under a dark overhang for my camera to capture well, the waves surge in behind me, finding a hole somewhere in my left welly.

Strawberry anemone

Undeterred by the steady seep of chilly water down my ankle, I take a close look at the tough seaweeds that have clung on at the edges of the pools through the winter storms. There are tufty pink fringes of coral weed, the frayed remains of last summer’s kelp, and, sprouting from the rocks at the pool’s entrance, there are dark clusters of wiry-looking Irish moss. Among these seaweeds are dozens of mauve stalked jellyfish dancing like fairy lights.

Stalked jellyfish – Calvadosia cruxmelitensis.

In every rocky crack and crevice alongside the pools there are crabs lurking, waiting for the returning tide. A velvet swimming crab watches me through red eyes like glowing coals.

Velvet swimming crab

Nearby, the sculpted pink spire of a painted top-shell brightens up a shady overhang that is also home to several cushion stars and bright sponges.

Painted top shell.

Everywhere I look there are colourful sea squirts, shells, fish and seaweeds. These may be the darkest days of the year, and I can feel a cold coming on, but the brightness of the shore always reminds me that spring is around the corner.

Breadcrumb sponge.

In fact, new life is beginning already in the rock pools. Before I leave I come across this 2mm long baby sea hare grazing on the seaweed. By the summer, if it survives, this tiny slug will have developed a striking brown leopard-spot colouration and will have grown large enough to fill my palm. Perhaps we will meet again?

Juvenile sea hare – Aplysia punctata

Happy New Year! May 2020 bring you health, happiness, and many, many beach adventures.

Happy New Year from Bernard the hermit! (Pagurus bernhardus).

Starfish and Blue-Rayed Limpets on a gloomy day

The clocks have gone back, endless bands of rain are pushing in from the grey sea and the UK government has announced there will be a general election during the festive season. It might be easier to hide under a duvet and attempt hibernation, but Junior and I have other plans. We grab a camera each and race to the rock pools in search of brightness and sparkle.

To the rock pools!

Millendreath beach near Looe is cold enough to warrant silly winter hats – mine has big ear flaps and Junior’s is a Christmas pudding – we don’t care what we look like as long as we’re comfortable. We head out onto a rocky outcrop that gives us some shelter from the north-easterly winds and begin our search. When I find a spiny starfish twice the size of my hand in the first pool we come to, we know it’s going to be a good day.

Junior takes a look at the tube feet on the underside of the spiny starfish.

Moving towards the sea, the gullies are full of leathery kelp and Junior knows just what to look for. The iridescent blue dashed lines on the shells of blue-rayed limpets are his favourite thing to photograph and at this time of year, some of the kelp is studded with these miniature jewels.

Blue rayed limpets on kelp – photo by Cornish Rock Pools Junior.

While Junior gets to work trying to capture these colours, I edge along the slippery rocks towards a tall overhang. Sponges and sea squirts coat the rocks in a huge range of hues from pinks and yellows to blues and greens. Among them are cowries, which feed on the sea squirts. One has abseiled down from the rock and is hanging by its mucous thread.

This Arctic cowrie has abseiled from the top of the rock and is still holding on to its thread of mucus.
A pair of Arctic cowries with their shells partly covered by their dark-striped mantles.

Nearby, a common starfish is trying to hide in a crevice but its bright orange colour gives it away. In the dark behind it, a Xantho hydrophilus crab is doing a better job of blending in.

A bright star on a gloomy day – common starfish at Millendreath.
Xantho hydrophilus crab hiding in a crevice.

For some reason the painted top shells here are paler than on those on our other local beaches and some are almost white. Another feature of this beach is the high population of sea cucumbers. We spot both the sea gherkin and the brown sea cucumber, but they are closed up today, hiding their frilly tentacles.

A pale and beautifully marked painted top shell.
Brown sea cucumber (centre) mostly hidden in a crevice, surrounded by sponges and other encrusting animals.

Just before we move out of this isolated gully, Junior shouts in delight. He has taken his best ever photo of a blue-rayed limpet. All the practice and patience has paid off.

Junior’s best blue-rayed limpet photo.
He’s also captured me at work in my natural habitat!

As the tide turns we take a quick look for stalked jellyfish. At this time of year, the seaweed is dying back making it easier to spot them, but the rushing currents from the stormy sea and the large amount of sediment that has been stirred up by the waves aren’t aiding our search. There are probably scores of stalked jellies here as the location is perfect for them, but we only see half a dozen. Among them are three different species: Calvadosia cruxmenlitensis, Haliclystus octoradiatus and a rather sorry-looking closed up specimen of Calvadosia campanulata.

This Calvadosia campanulata stalked jellyfish has (hopefully) seen better days!
The only Haliclystus octoradiatus stalked jellyfish we find is being thrown around in the current, but the white blobs of its primary tentacles can be clearly seen in this photo.
Most of the stalked jellyfish we see today are the ‘Maltese cross’ stalked jelly – Calvadosia cruxmelitensis.
Calvadosia cruxmelitensis stalked jelly with lots of white spots – these spots are clusters of the stinging cells (nematocysts).

Junior spends a happy half hour watching the cracking cliffs of sand that have formed around the edges of the rain-swollen stream, until the incoming tide begins to send waves up the river, flooding the sand around us and forcing us back.

The first spots of drizzle spatter down and will soon be followed by yet more heavy rain. There’s nothing we can do to prevent the arrival of even shorter days or colder weather, but whenever we need to find colour and inspiration during the dark winter, we will know where to find it.

Berthella plumula sea slug
A breadcrumb sponge with microalgae growing inside the green parts.
Star ascidian
A tortoiseshell limpet surrounded by pink encrusting seaweed.

Happy rock pooling!

Huge thanks to everyone who has shared their finds and photos with me. I love hearing about your rock pooling adventures through my contact page.

Rock Pool Bingo – Searching for Southerly Species (Part 2 – North Coast)

With our bingo cards of southerly species part-filled after an exciting day on the south coast, our visitors from Wales still had quite a wish list left to accomplish. To find cup corals and Celtic sea slugs, a trip to a more exposed coast would be needed. Naturally, I suggested my favourite beach: Porth Mear.

A flock of geese joined us on the shore at low tide.

The weather was on our side, taking a break between the endless storms that have characterised the summer holidays. So, with swimmers and beach shoes at the ready, we walked down a valley alive with tortoiseshell butterflies to where the bluest sky met the bluest sea. Even the pools at the top of the beach churned with trapped young mullet, scurrying shore crabs and bright anemones. While one of our friends stayed looking at the upper shore pools and gathering shells, Junior and I led our other friend on a long slip and slide across the rocks to reach our goal.

With two hours to go until low tide, we could safely allow ourselves a few distractions on the way. I couldn’t resist stopping to take photos of this wonderful Montagu’s blenny, which let me creep ever closer with my camera as it sheltered under a limpet shell. Blennies are able to move their eyes independently and this one kept an eye on me while scanning the surface of the pool with the other.

Montagu’s blenny looking two ways at once. This blenny has a single head tentacle.

My friend was delighted. Although it hadn’t appeared on our bingo card, the Montagu’s blenny is another southerly species which he had never seen in North Wales. This was too easy!

We had met some St Piran’s hermit crabs at Hannafore the previous day, but the colony here was well worth a look too. We found scores of these crabs in and around the pools along a couple of rocky overhangs, living in a range of sizes of shell. This species is doing well here, towards the northerly limit of its known range.

The painted top shells on this beach are always especially pink and beautiful, perhaps because in this more exposed location, they tend to accumulate less silt and micro-algae on their shells. We stopped to take plenty of photos.

A typically bright pink painted top shell at Porth Mear.

Although it can be hard to find stalked jellyfish in the summer when the beach is thick with the seaweeds they attach to, we were determined to tick one or two off the list, especially Haliclystus octoradiatus. This may not be a particularly southerly species, but it occurs frequently around Cornish coasts. After much searching we found a very small blob that was probably a juvenile, but I could only confirm that by looking at photos afterwards.

This tiny juvenile Haliclystus octoradiatus stalked jellyfish was only a few milimetres long, but in the photos, its primary tentacles are visible.

As the tide dropped further, we picked up our pace and clambered towards a wave-battered gully. This area is only accessible on the lowest tides and, even then, is often out-of-bounds due to the huge swells that pound these rocks for much of the year. Today, the calm conditions were perfect and we could explore in relative safety while keeping an eye on the time.

Junior made straight for the high rocks, where he quickly found the first Celtic sea slug, out in the open among the barnacles and mussels.

Celtic sea slug

These strange black lumps always remind me of armoured cars. This is mainly a very southerly species which is found widely around exposed Cornish coasts, but it has been recorded as far north as the Farne Islands and Scotland.

Celtic sea slugs may not be the most classically pretty slugs, but they are incredible animals. They are able to survive on these rough shores in terrifying conditions and they don’t even have gills. They breathe air and hide away in cracks in the rock when the tide comes in, staying alive by keeping an air pocket sealed inside their bodies and breathing through their skin when needed.

If there is one Celtic sea slug, there is usually a whole colony and we found dozens more on the rocks all along the gully.

Celtic sea slug foraging on tiny micro-algae and other micro-organisms.

Our next stop was a deep overhang with a pool at its base where we knew we would be able tick off another species from our bingo card, the scarlet and gold cup coral.

We had to kneel and lie at strange angles on rocks encrusted with sharp barnacles, but we were soon rewarded with the brilliant glow of many corals.

Scarlet and gold cup corals

These tiny orange and yellow corals open their transluscent tentacles in the water here and always astound me. Their delicate soft bodies encase a spongy, fragile exoskeleton, none of which looks like it could stand up to a gust of wind, let alone the fierce, pounding seas that rage through this gully on a daily basis. Despite their soft appearance, scarlet and gold cup corals, like the Celtic sea slugs, thrive in these wild places.

It was a good thing we had left ourselves plenty of time to explore this rock pooler’s paradise. Between deep pools packed with enormous snakelocks anemones and prawns as big as my hand, we scrambled and stared at the huge diversity of species in front of us. Arctic and three-spot cowries moved across the damp surfaces encrusted with pink seaweeds and colourful sea squirts. Groups of light-bulb sea squirts seemed to shine out from the dark water and so much life abounded on every surface that we moved with great caution for fear of accidentally treading on creatures.

3-spot cowrie

The underside of a large boulder at the head of the gully was coated in a red sponge. A quick inspection revealed a small white coil of sea slug sponge. It took me longer to find the slug, which matched its background flawlessly. Rostanga rubra are a common find on these sponges but this was another first for my friend who is almost as obsessed with slugs as I am. He was so delighted with this little find that he took some persuading to move away from the gully before the tide turned.

Rostanga rubra sea slug
Rostanga rubra sea slugs feed on orange and red sponges such as Ophlitaspongia papilla. As they feed they take in the colour from the sponge, which makes them perfectly camouflaged.

On our way out of the gully, we waded through a pool, up to our waists in the water and no longer caring how wet we were. Hidden at the back of the pool we discovered a deep hole in the rock that harboured dozens of scarlet and gold cup corals and many large snakelocks anemones. I spotted a leg sticking out from underneath this one and uncovered this Leach’s spider crab (Inachus phalangium) sheltering there.

Inachus phalangium living in the shelter of a snakelocks anemone’s stinging tentacles. This crab also grows sponge on its carapace for camouflage.

A shallow pool nearby was dotted with tufts of rainbow weed. To our surprise, these harboured many Asterina phylactica – a small species of starfish. A nearby clump of codium seaweed was also home to several Elysia viridis sea slugs.

Asterina phylactica – a small species of cushion star.

On our way back across the beach, my friend found a clump of seaweed with half a dozen stalked jellyfish growing on it. This time, the blobs of the primary tentacles between the arms were easy to spot and we could be sure that these were Haliclystus octoradiatus.

A white Haliclystus octoradiatus stalked jellyfish

With most of our bingo card of southerly species complete and with another day of rock pooling to try to find the remaining species, my friend set off up the beach to rest and enjoy a well-earned picnic.

Junior and I lingered in the sunny pools, exploring further into the slippery masses of thong weed and kelp until the tide turned.

To celebrate the rare August sunshine, we finished the day with a visit to the vast rock pool where I used to swim as a child. Plunging into the cool waters, I experienced the familiar feelings of wonder and trepidation at the thought of what might lurk in the depths.

We splashed and floated between the rocky walls, finding starfish, prawns, star ascidians and sponges as we swam, side by side. Time might move on, but this beach never loses its magic.

Sea hare, Aplysia punctata, at Porth Mear
A blue-rayed limpet on kelp at Porth Mear
A yellow form of the Scarlet and gold cup coral.
A huge prawn checks out my camera!
A shanny (common blenny) hiding in a crevice waiting for the tide to come in at Porth Mear.
Light bulb sea squirts at Porth Mear.
The walk to and from Porth Mear is always a wonderful part of the adventure – Junior spotted lots of cinnabar moth caterpillars on our way back.