Wishing on a Rosy Feather Star

It’s been a while since I posted – thank you for bearing with me. I have so many rock pool adventures to share. I hope you will love this rosy feather star as much as I did.

“Do you see many feather stars?” Libbie asks. We’re on a favourite north coast beach, where we randomly first met a few months back. This time, she has brought her sister in law, Lynne, whose joyous rockpooling Twitter feed I highly recommend: lynne (@lynne08777205) / Twitter.

Asterina phylactica cushion star among seaweed
An Asterina phylactica dwarf cushion star among the seaweeds – one of our first finds of the day.

I admit that I have never seen one. Neither have Libbie or Lynne. I am convinced feather stars are somewhere here on this very beach, but it feels as though I’m looking in the wrong way. Perhaps between us, we’ll spot one? We all agree that sometimes you find things just because you have decided to. This, we say, will be our lucky day.

There is plenty to keep us occupied, including some new life. This is good to see after the heat-bleached seaweeds and poor water quality we have experienced around the coast over the summer. Young Montagu’s blennies flit between the rocks and turn their large eyes to watch us. Libbie discovers a juvenile white-ruffed sea slug (Aeolidiella alderi) under a small slate.

Juvenile Aeolidiella alderi slug found by Libbie.
The second slug of the day – another gorgeous white-ruffed sea slug, Aeolidiella alderi.

Nearby, an even smaller solar powered sea slug, Elysia viridis is out in search of seaweeds to eat. Under my camera, we can see the green and turquoise colours, clues to the presence of chloroplasts from algae it has consumed, which are still photosynthesising – making glucose inside the slug’s body.

A “solar powered” sea slug – Elysia viridis

While the tide recedes, we take a leisurely look into pools packed with St Piran’s hermit crabs and discuss Lynne’s wishlist for the day (Celtic sea slugs, Scarlet and gold cup corals and blue-rayed limpets). They are all species that don’t move far or fast and conditions are ideal.

Excitingly, there are some very small baby St Piran’s hermit crabs like this one in the pools. The next generation is doing well.

Junior, who now knows these rocks as well as I do, sets a course across the slippery stream bed towards an area where we’re almost sure to find everything we’re looking for.

The painted top shells come in especially striking colours on this beach.

As always, progress is slow. There is so much to see and we can’t resist checking every pool. There are vivid pink painted top shells and all sorts of fish and crabs. To my excitement, we find a species I haven’t noticed before, Perophora listeri – a cluster of small bubble-like sea squirts on the red seaweed.

Perophora listeri sea squirts
Perophora listeri sea squirts

In a wide pool near to where Junior is searching for Celtic sea slugs, we settle down to look closely at the rainbow wrack. Not only is this bushy seaweed a brilliant iridescent turquoise color and a favourite place for catsharks to lay their eggcases, it is also teeming with life, like a miniature forest.

Pheasant shell
A cowrie moving over an Asterina phylactica cushion star and a turf of other creatures.

Pheasant shells roam the canopy, young anemones cling on like epiphytes and the dense animal crust of sponges, sea squirts, hydroids and bryozoans around lower ‘branches’ attracts cowries and other small predators. Pretty Asterina phylactica cushion stars are everywhere and as I look down into the base of the seaweed, something else grabs my attention.

There is a bright pink, branched shape that doesn’t look like seaweed. I crawl in close to get my camera in position, but I already know what it is. “A feather star!” I gasp. It seems ridiculous to find one just because I’m looking, but there it is.

Our first rosy feather star!

As we watch, the rosy feather star extends and retracts its arms, uncurling them to show the alternating twiggy branches along the sides. These are fringed with a little comb-like structure to catch passing food. The animal is clinging onto the seaweed with its hooked pink-striped “cirri”. It is such a shocking coral pink colour that it seems impossible I would overlook one, but it is well hidden under the seaweed and camouflaged against the crust of pink seaweed and the coral weed that lines the whole pool.

Convinced there must be more feather stars here, I search for a while without success. In the meantime, Junior has found everything on today’s wish list and is keen to show Lynne and Libbie before the tide comes up. Sure enough, we are treated to scarlet and gold cup corals, blue rayed limpets and quite a battalion of Celtic sea slugs!

Celtic sea slug
Blue-rayed limpet on seaweed

Soon the oystercatchers are moving up the shore with the tide and it is time to retreat. We sit at the top of the shore, watching kestrels hovering over the clifftop while we enjoy a much-needed picnic. Buoyed by our success with the feather star, we reckon we should carry on actively looking for unlikely things next time. Soon, we have a whole list. Cuttlefish, octopus and seahorses, here we come!

A few more bonus creatures from our day’s rock pooling!

Clingfish sp. – probably small-headed clingfish.
Candelabrum cocksii hydroid
Botryllus leachii colonial sea squirt
A pretty chiton (a type of mollusc). Lepidochitona cinerea

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

Rock Pool Highlights in Looe

As anyone who takes notice of the natural world knows, nothing stays the same. I visit my local beaches around East Looe so frequently that I know every rock and every pool. Yet, the more time I spend here, the more I notice.

Sitting by a pool for a long time, I notice more and more detail, like this tiny needle whelk.

Sometimes I learn something new about a familiar animal, sometimes I am treated to fascinating displays of natural behaviour, and sometimes I find species I never seen before. Here are five recent highlights from my local beach.

There’s always something new to see… in this case it’s Other Half in his new waders.

Cushion Star Hatchlings

It took me many years to realise that cushion stars lay eggs and to finally see my first just-hatched babies. Now I know what to look for, I see their eggs everywhere in the summer rock pools.

So many baby cushion starfish (Asterina gibbosa), fresh out of their eggs.

I find a cluster of new, tiny cushion stars and fall in love with their bright orange perfection and impossibly small tube feet.

Cushion stars – these baby starfish have just hatched and are setting out across the pool on their little tube feet.

A Hermit Crab Without a Shell

The thing that everyone knows about hermit crabs is that they live in the empty shell of a sea snail. It’s not entirely true to say that they have no shell of their own though. Hermit crabs have tough claws and shell covering the front part of their body. Just like other crustaceans, they moult their shell each time they grow.

A St Piran’s hermit crab, East Looe. This hermit crab’s rear end is comfortably housed in a shell.
Moulted shell of a St Piran’s hermit crab. Hermit crabs have shell covering the front part of their bodies. When they grow, they moult their old shell, leaving it behind.

Hermit crabs don’t, however, have a shell on their rear end. Instead, they have a long, spiral tail, which is soft and bendy. When the hermit crab finds a suitable shell to live in, it winds its tail up through the internal structure of the shell, clamping its home in place.

If a hermit crab loses its shell to another crab or a predator, it finds itself in a real predicament. That soft tail is vulnerable to attack.

Hermit crab out of its shell
Hermit crab out of its shell, showing its curly tail.

When Junior and I come across a homeless hermit, we locate a suitable empty shell and watch what the crab does.

The whole process is astonishingly quick.

Nudibranch Sea Slug – Eubranchus exiguus

Regular readers will be well aware of my (entirely justified) obsession with sea slugs. If you aren’t already aware of how exquisite these little animals are, you might like my introductory talk for The Shores of South Devon.

Most UK sea slugs are small and some are so tiny that you can barely see them with the naked eye. I spot a speck of jelly on some seaweed and spend the next twenty minutes crouching in the water to try to focus my camera on it.

Eubranchus exiguus – a nudibranch sea slug, Looe, Cornwall.

The slug is moving, the seaweed is moving and my hands are far from steady, but the photos are good enough. Meet a species of nudibranch sea slug that is new to me: Eubranchus exiguus.

Eubranchus exiguus sea slug, showing the distinctive shape of the cerata on the slug’s back.

The long, inflated cerata on the back of this sea slug look like they have been pinched in near the top, giving them a vase-like shape. Scattered white flecks adorn its body. When I can get it in focus, it is a fabulous-looking creature.

The Eubranchus exiguus slug on seaweed with my finger in the background to give an idea of scale. It was around 2mm long.

Rock Goby Eggs

There are few things more mesmerising than fish eggs. They are generally transparent, meaning that you can see the babies’ eyes looking out at you. As the fish grow, they become fidgety, twisting and turning inside the egg. Rock gobies are a very common rock pool fish and their distinctive capsule-shaped eggs are usually well-guarded by the father, who stays close until they hatch.

Rock goby eggs. Looe, Cornwall.
Rock goby eggs

Doto slugs (and a bonus slug)

Finding sea creatures in the pools is a haphazard business; you can rarely be sure of finding even common species. However, if I want to find a Doto sp. slug, I know just where to look.

In places around my local rocks, the brown seaweeds (wracks) are so completely covered in hydroids that they look like they have grown beards. Very close-up, these hydroids (Dynamena pumila) look like stacks of pale triangles. Among them, feeding on the hydroids, are the tiniest splodges of jelly – the Doto slugs.

Doto sp. slug – possibly Doto onusta. Looe.

Out of the water, they are a sorry, squidgy mess. If, however, I can persuade one off the hydroid, I can put it in the water to reveal its towering jelly-mould structure decorated with charming crimson or black dots. The satellite dish rhinophores (antennae) on the slug’s head are an impressive accessory too.

Doto sp. slug – possibly Doto onusta. Looe, Cornwall.

Whether they remind you of cakes or jellies, there’s something gloriously edible-looking about the Doto slugs.

Warning: Slugs are not dessert. Don’t eat rock pool wildlife.

The little spots on the slug’s cerata look so much like cherries on a cake. Doto sp. slug, Looe.

It isn’t clear what species these slugs are; Doto slugs are notoriously difficult to identify. They were initially thought to be Doto coronata. That species isn’t now believed to feed on Dynamena pumila, so they may be a species known as Doto onusta – or something else. Whatever they are, I absolutely love to see them.

And now for a bonus slug… The orange-clubbed slug, Limacia clavigera, is a frequent find, but is too fabulous to be left out. Enjoy!

The orange-clubbed sea slug, Limacia clavigera. Looe, Cornwall.

Have you found anything new on your local beaches? I love to hear what other people have seen and can often help to identify unusual finds if you’d like to get in touch.

You can also find identification guides to some common rock pool creatures such as crabs, starfish and fish on my Wildlife page.

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

Rock Pooling at Lizard Point: Cowries, Sea Slugs and a Saffron Bun

It’s not exactly tropical, but we’re as far south as you can go on the UK mainland. The sun is shining and the clear water gives us a perfect view into the pools. After a morning of geological exploration at Kynance Cove, my family are treating me to some low tide rock pooling here at Lizard Point.

Rock pools at Lizard Point

Apart from the chatter of seabirds and a distant hum of voices from the cafés perched on the cliffs, the beach is still, expectantly waiting for the tide to turn. Out in the bay, a bull grey seal rests upright in the water. He is ‘bottling’, his broad snout raised to the sun, keeping half a sleepy eye on the female that is snoozing closer to the shore. There are no boats here to disturb the seals, so they nap peacefully on and on, barely moving with the gentle rise of the swell.

The colours in the pools are as vivid as a royal procession. Neon green snakelocks anemones jostle for space with dusky pink coralline algae, yellow sea squirts and iridescent blue seaweed. Tiny rainbows play across the rocks.

A colourful pool at Lizard Point – Snakelocks anemone

Looking closer, we begin to notice other rock pool wildlife that is less keen to stand out, adopting the same bold colours as the seaweeds and encrusting animals to hide from predators. Tiny Elysia viridis sea slugs are everywhere, but they match the deep green of the codium seaweed perfectly.

Elysia viridis on codium seaweed.

These are the ‘solar powered’ sea slugs. They retain the seaweed’s chloroplasts, which carry on photosynthesizing in their bodies, making glucose to supplement the slugs’ diet.

Elysia viridis sea slug stretching out to make the most of the sunlight. Spot the second slug!

A variety of animals are resplendent in shocking pinks and oranges, which allow them to disappear among rocks adorned in pink paint seaweed and forests of other red seaweeds. A European 3-spot cowrie (Trivia monacha) is roaming the rocks looking for sea squirts to eat.

Trivia monacha – the European 3-spot cowrie at Lizard Point. It feeds on sea squirts like the blue star ascidian to the left of the photo.

With its sunset-orange proboscis fully extended and its spotty mantle draped over most of its shell like a (fake) fur cape, it has the air of a glamorous Dalek.

European 3-spot cowrie (Trivia monacha) doing a Dalek impression

Not to be outdone by the molluscs, there are some stunning worms in the pools. My favourite is this syllid worm, gliding across the rock with its enormously long, whisker-like appendages stretching and curling in all directions at once.

Syllid worm. Amblyosyllis sp. looking spectacular. Lizard Point, Cornwall.

This feels like a spot that sea slugs should like. There is a variety of food on offer and no shortage of hiding places among the pools and boulders. Sure enough, under one rock I find two species hanging out together. They look like friends, but they are on separate missions. The great grey sea slug (Aeolidia filomenae) feeds on anemones, while the Berthella plumula – or feathered Bertha as I like to call it – eats sea squirts or sponges.

A quick hello in passing – Great grey sea slug (Aeolidia filomenae) and Berthella plumula sea slugs.

Junior, who excels at gathering people to look at things, has collected up an excited young boy and his grandfather to show them the pools. We all find things to show them – solar powered sea slugs, hermit crabs and a stalked jellyfish. While Junior is explaining barnacles to his fascinated audience, I wander down the shore, thinking I might find a starfish for him to show his new friend.

Stalked jellyfish (Haliclystus octoradiatus) on codium seaweed at Lizard, Cornwall. Photo by Cornish Rock Pools Junior

Sheltering under a small stone is a neat five-armed cushion star, but close to it, even more excitingly, there is a slender little Aeolidiella sp. sea slug.

This slug looked a little different: Aeolidiella glauca

Aeolid slugs vary in colour depending on what they have eaten, but there is something unusual about this one that I can’t place. It has a bit of a white ruff behind its head, but I’m not convinced it is the white-ruffed sea slug (Aeolidiella alderi) that I frequently see.

Aelolidiella alderi (pictured near Falmouth) is the more common species locally. It is often white or grey, but can take on bright colours like this after eating anemones.

I take some photos. Zooming in, I soon ‘spot’ the difference; the difference is the spots! There are tiny white flecks on the slug’s body. I take photos in the pool before ensuring it is returned safely back under its stone.

Aeolidiella glauca sea slug, Lizard, Cornwall

Despite my rush to identify the slug (which I suspect is an Aeolidiella glauca) there are even more important things to do on the way home: like stopping for a saffron bun and ice creams at Roskilly’s, and visiting friends in Gweek.

Thanks to the wonders of expert Facebook groups and also the brilliantly helpful David Fenwick of Aphotomarine, I have confirmation the same day. Aeolidiella glauca has occasionally been recorded in this area before, but it’s a first for me. It may be more common in northern waters, but marine creatures rarely follow the rules.  There are surprises everywhere and that is exactly what makes rock pooling so fabulous.

Another lovely little find: Lamellaria latens (gastropod mollusc) at Lizard Point
Dahlia anemone at Lizard Point, Cornwall
Gem anemone. Lizard Point, Cornwall.

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

Beach Explorers at Filey Literature Festival

The empty shells of sea potatoes, masked crabs, swimming crabs, razor clams and limpets fill my arms, along with a rather battered piece of seaweed. We haven’t reached the rock pools yet, but the sharp-eyed kids at my Beach Explorer book event have done as instructed and brought me all of the strandline treasures they can find. That, it turns out, is a lot!

Spotting signs of life in the sand at Filey: Photo by Filey Literature Festival

The long, sandy beach here at Filey in Yorkshire provides a perfect environment for sea creatures that like to bury themselves in the sediment and the evidence is everywhere. The beach is covered in the tiny tubes of sand mason worms and we have no difficulty finding the coiled casts of lugworms that live in burrows beneath our feet.

The habitat is perfect for sand mason worms.

The cliffs of the headland at Filey Brigg are a fascinating mix of rock types, but look ominously unstable, so we trace a path along the sea’s edge, well clear of any danger. Fish, crabs, anemones and starfish are the top things the kids tell me they hope to see. The silty water among the boulders and pools at the base of the Brigg will make our search challenging, but the children are in good spirits and full of enthusiasm.

Beach Explorer rock pooling event at Filey Brigg. Photo by Filey Literature Festival.

On the rocks ahead of us, kittiwakes are swooping down and gathering clumpy beakfuls of seaweed to line their nests. On my walkover of the area yesterday before my evening book talk, I melted with joy at the unmistakeable calls of these pretty little gulls. Sadly, it’s a sound I rarely hear back in Cornwall these days.

The clear limestone pools at the end of the Brigg also took me by surprise yesterday. The distance across slippery boulders made them unsuitable for today’s family event, but I couldn’t resist exploring and delighting in finding fat sea hares, oaten pipe hydroids and lots of busy hermit crabs.

The rocky shore at Filey Brigg
Sea hare, Filey, Yorkshire
Tubularia hydroid. Filey.
Elysia viridis – the solar powered sea slug. Filey, Yorkshire.

Despite the challenges of our muddy site, the finds come rolling in to our ‘shore laboratory’ tray. We soon have a baby sea scorpion fish, tiny brittle stars, shore crabs, a hermit crab and more.

A beautiful beadlet anemone with its tentacles out. Filey. Yorkshire.

We even find a great grey sea slug and a large female shore crab with a spongey mass of eggs under her tail. With a bit of help and perseverance, everyone finds sea creatures and the children (and their adults) do a perfect job of looking after their finds – keeping them in plenty of sea water, handling them gently and returning them to their homes.

An empty clotted cream pot is perfect for making a mini-aquarium for our sea snails so we can see their tentacles emerge. Photo by Filey Literature Festival.

It’s a long way from Looe to Filey but seeing the faces of the children as they find their first crab moults, see their first open anemone and hold their first hermit crab, makes it all worth it.

Hermit crab (Pagurus bernhardus) at Filey, Yorkshre

My children’s book, Beach Explorer, is all about discovering the beach for yourself through hands-on activities and I couldn’t have asked for a better group of explorers. If these families are anything to go by, Yorkshire has some fine young naturalists in the making!

Beach Explorer is available from your local bookshop and online.

A huge thank you to Filey Literature Festival for hosting me, Hylands Care Home for kindly sponsoring the events and to everyone who came along for your warm welcome and enthusiasm. Also, thank you to the Hull University Marine Biology Department students and lecturer who generously shared their knowledge of the beach and to the pod of dolphins who treated me to a swim-past on my last morning walk in Filey.

Filey Literature Festival – off to a great start!
The rather wonderful crazy golf course on Filey seafront!

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

It’s Conger Time! Low Tide Rock Pooling Surprises.

No matter how many times I go rock pooling, something always takes me by surprise. It helps that I’m constantly awestruck by simple things: the blue flash of a kingfisher zipping over the pools; the unfurling tentacles of a fanworm; a seaweed-covered stone that turns into spider crab – sprouting legs and walking off.

Today, Junior and I are looking for little cuttlefish because that’s what we always do in shallow, sandy pools. We won’t find any, but that never matters. Whatever turns up will be the best thing ever.

It can take a while to get your eye in, but seemingly empty rock pools are full of life.

Although the pools look deserted, I know they’re not. I stand still in the water and am reminded of games of ‘Grandmother’s Footsteps’ in the playground. There are flickers of movement at the edges of my vision, yet each time I look towards them there is nothing but clear water covering smooth sand.

A dragonet is the first creature to break cover, gliding noiselessly in short bursts. Every time the fish stops swimming, my eyes struggle to make out its triangular, small-mouthed head or slender tail against the sand. Only the orange glint of its eyes, which protrude from the top of its head like a cartoon drawing, give the dragonet away.

Dragonet resting on gravelly sand. Having eyes on top of its head gives it great vision of what is going on all around.

It takes me several attempts to lower my camera into the water. The fish darts away at the slightest disturbance. Even close-up, the wavy blue patches and dark saddle patterns on the fish’s back blend with the colours of the sand. Sometimes I take a photo and realise afterwards that the fish isn’t in it.

Dragonet in a sandy pool

The sand in the pool is pock-marked with tiny craters. Keeping my camera in the water I wait for the creators of this miniature battlefield to reveal themselves. After a few moments, I am rewarded with a frantic jet of sand shooting out of the bed of the pool to my left. Another erupts to my right.

Zooming in to the source of the sand-flinging I can see a solitary common shrimp, digging like an eager puppy, throwing sand out in every direction as it sinks deeper into the pit it has made.

Brown shrimp digging

A minute later, it moves on to another spot and resumes its endeavours. All around me, other shrimps are digging in earnest to find food. If I move at all, they fling sand over themselves until only their googly eyes are still visible.

Digging brown shrimp

Small, brilliantly camouflaged, gobies also flit about the pool, occasionally photo-bombing my attempts to photograph the shrimps. These may be sand gobies or common gobies; it takes close examination to separate the two species and they have no plans to stay still for long enough.

Brown shrimp – and a young green shore crab (bottom right)

We follow the tide, pulled ever further out through the pools by our curiosity, exploring under rocks and among the seaweed until we are at the seaward edge of the rocks. In the summer we snorkelled just a few metres from here at mid-tide, seeing small spotted catsharks, wrasse and comb jellies over the seagrass and kelp.

Kelp provides a wonderful habitat for other species, including this sea mat bryozoan (Membranipora membranacea).
Membranipora membranacea – even closer-up showing the rectangular autozooids and feeding tentacles extended.

Junior finds a south-clawed hermit crab (Diogenes pugilator) that has been washed in by a wave. We place it in a more sheltered spot and it has disappeared in seconds, burrowing into the soft sand.

Diogenes pugilator hermit crabs have a very long left claw.

By this point my hair is soaked from putting my head close to the dripping-wet seaweed that hangs over the rock faces, looking into every nook and cranny. I can see that Junior is plastered head to toe in sand from building a huge tide fort. It’s a happy sort of look. In any case, there’s nobody here to judge us apart from some whistling oystercatchers and they are too busy impaling limpets to worry about us.

Short video of brown shrimp, sea spider and hermit crab in action.

Crawling up to a small overhang with my chin almost touching the sand, I lift the fringe of sea lettuce aside and meet today’s surprise. A large, amber eye, as big as my own, is looking back at me.

Conger eel
Conger eel

It belongs to a sharp-nosed brown fish whose body is hidden by the deep, dark hollow beneath the rock. I move my own nose back a little from its long, sharp jaw.

If this is what I think it is, that body will be long and the jaws contain a powerful set of teeth that make it an efficient predator.

Junior knows I only call him away from his work when there’s something truly exciting to see and I am massively excited. I’m pretty sure this is the first conger eel we have ever found on the shore.

Do-do-do…. Conger eel under an overhang exposed by the low tide.

For a moment, we wonder if it is alive. There is hardly any water under the overhang and the fish doesn’t move. I sloosh some water from the pool through the gap in the rock and the fish repositions its head to take in the oxygen. The tide is already on the turn so it will be fine.

I take a couple of photos, pour some more water into the overhang and leave our fish-friend in peace.

It’s a good thing there is no-one to see the pair of us, covered in sand, dripping wet, dancing and singing our way back off the beach with the waves at our heels. It isn’t most people’s idea of a beach party and the pun is terrible, but we couldn’t care less.

“Do-do-do. Come on and do the conger!”

Happy New Year! Here’s to all of you who have done your bit to help wildlife and make the world a better place in 2021.

With thanks to the experts on Facebook groups who confirmed I was correct in my feeling that the fish looked ‘congerish’.

Some other finds from this expedition…

Blue-rayed limpets
Sea slug! The first time I have found Palio nothus in this location. This nudibranch slug has wonderful tall helter-skelter rhinophores on its head and a circlet of fluffy gills on its back.
‘Kelp fir’. Obelia geniculata hydroids on the kelp, looking like a wintery forest.
A sea spider – probably Nymphon sp. Look at the little spidery shadow it’s casting on my hand.
Crouching rockpooler, hidden dragonets

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

Christmas Rock Pool Catch-up

As you may have noticed, blog writing has been relegated to my ‘to do dreckly’ list for a couple of months now. In September, I unexpectedly started a job that I didn’t know I’d applied for and my photos of rock pooling trips, including this day at Prisk Cove, have been piling up ever since. It’s time for a catch-up!

A swimming variegated scallop was one of the highlights of this short video I put together at Prisk Cove this autumn.

For once, the gales and mizzle held off for our visit to Prisk Cove, making it an ideal day for sitting by the pools and staring. The longer I looked the more I discovered.

This Aeolidiella alderi sea slug had recently munched its way through a Daisy anemone, turning the cerata on its back from white to a deep, speckled brown. It is sometimes called the ‘white-ruffed’ slug due to the paler cerata that form a smart collar behind its head.

Aeolidiella alderi – the white-ruffed sea slug

Finding a nudibranch sea slug made an auspicious start to the day, and there were plenty more discoveries in store. Many of the tunicate sea squirts I find on the shore are dull brown, but this Ascidia mentula was an explosion of colour.

Ascidia mentula
Up close, the Ascidia mentula sea squirt looks like a riotous display of tiny red fireworks

Nearby, a chiton nestled among the barnacles, moving very slightly as I watched. These unassuming little molluscs have changed very little since the Devonian period. You have to look closely to appreciate their varied patterns. There are several species commonly found on our shores and some – like this one – have clusters of bristles fringing their armoured plates.

Bristly chiton
Bristly chiton

Flatworms are far more exciting to watch than chitons. They are speedy for their size, flowing seamlessly over rock and engulfing any obstacles they meet.

This remarkably bright flatworm is a Cycloporus papillosus. I mostly see them in shades of star-studded blue, but this one has other ideas. They vary in colour to match their equally resplendent prey, the star ascidian sea squirt.

Caught crossing the rock in search of new food supplies, this flatworm was easy to spot. Once it is on a sea squirt, it will become almost invisible.

Cycloporus paplillosus flatworm, normally found on star ascidian sea squirts.
The colourful Cycloporus papillosus flatworm lives on star ascidian sea squirts like these.

Rocky overhangs are my happy place. They’re a kind of lucky dip with fascinating creatures hiding in every single one. I wouldn’t advise putting a hand in an overhang as there’s almost always a crab lurking at the back, but it’s worth going through the contortions required to obtain a good view of what lies within. This spiny starfish, however, wouldn’t win any games of hide-and-seek.

Spiny starfish
Always watch your fingers when there are velvet swimming crabs about. This one had especially blue claws.

Unlike the starfish, my next find was a master of disguise, hugging the rock and changing colour to match it. Only the googly eyes and a tiny fluttering fin gave this topknot flatfish away.

Topknot checking out my camera
Pressed against the rock, the topknot is almost invisible.
Topknot flatfish swimming.

Among boulders encrusted in colourful sponges, I was delighted to find my favourite slug: “Discodoris” – the Geitodoris planata. This one was busy tucking into the sponges and sported plenty of acid glands to ward off any would-be predators, visible as white patches on the slug’s back.

Geitodoris planata enjoying a feast of sponges.

Tortoiseshell limpets can go unnoticed due to their diminutive size, but they have one of the prettiest shells on our shores. This one, nestling among the pink seaweeds, was a perfect burst of pink and blue.

Tortoiseshell limpet Tectura virginea

I always tell people that they should go slowly and look closely to see and appreciate wildlife. It works every time and is good advice for life in general, yet it’s advice I sometimes forget myself. In my haste to find the next thing, I can easily miss what is in front of me.

This quiet, meandering day at Prisk Cove, was a rare chance to truly stop and look, to watch animals doing their own thing. From the mysid prawns flocking around the snakelocks anemones to the way the green shore urchins had arranged their shelters of seaweed, pebbles and shells, there were endless insights into rockpool life. If the tide hadn’t come in, I would happily have stayed for many hours, staring into those perfect pools.

Nadelik lowen! Merry Christmas! Wishing you a happy and restful time.

Mysid prawn hovering over a snakelocks anemone
“The urchin’s got his hat on…” – Green shore urchin using a limpet shell for shelter.

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

Wonderful Worms and Other Squidgy Things at Prisk Cove

After the summer rush, Cornwall is starting to breathe again. Our usual autumn trip to Brittany was cancelled months ago, but we’re making up for that with an exotic adventure to visit friends on the Lizard. Junior disappears off to play leaving some of us adults to our own devices. Rockpooling it is then!

We’re unsure how productive this session will be; there is a definite change in the air this week. Huge ships are still lurking in the shelter of the bay after the recent storms and kelp is starting to pile up on the strandline. The stiff breeze makes it hard to see into the pools at times and I’m glad of my waders to keep me warm and dry.

Prisk Cove at low tide

In the distance there is a small group, perhaps from Falmouth University or the Rock Pool Project. It’s an unusual sight this year. So many events have been cancelled. It makes me think of how my Wildlife Watch groups and how much the children have missed out on. I’m not ready for close contact with groups just yet, but perhaps it won’t be long now.

This is the season of blue-rayed limpets. They will soon grow and move down into the holdfasts of the kelp but for now they glitter against the seaweed on which they feed. Some fronds of kelp are pockmarked with holes that these tiny molluscs have carved out.

Not all the blue-rayed limpets are on kelp. This one is tucking into seaweed on a rock.

Things may be winding down for the winter but the intensity of colours on the shore is as strong as ever. Even the sand is a treasure trove, a kaleidoscope of shell fragments interspersed with pieces of the knobbly skeletons of calcareous algae. The closer I look the more I see.

‘Maerl’ sand at Prisk Cove – made from the skeletons of dead calcareous algae.

There are three species of red seaweed that form beds of these loose pieces, collectively known as maerl. The top layer of live algae exposed to the light is a deep pink, while underneath the dead layers bleach to look like pale pretzel fragments. Offshore, these seaweed can form deep beds, which provide endless hiding places for small marine creatures.

Deep pink ‘maerl’ type calcareous algae.

This beach is always rich in brightly coloured worms, sea squirts, sponges and other animals that I tend to unscientifically group together as squidgy things. They aren’t all easy to identify – especially the sponges, which often require a microscope – but some creatures, like this strawberry worm (Eupolymnia nebulosa), are easy to recognise.

Strawberry worm (Eupolymnia nebulosa)

Unafraid to mix spots and stripes, this lipstick pink terebellid is one of the most glamorous worms on the shore. It sports a fringe of stylish bristles and crowns its unique look with an expansive mop of tentacles and bushy red gills.

Strawberry worm (and friends).

Elsewhere, some of the rocks and seaweeds are covered in a layer of squidgy things.

The eye-catching collage of flower shapes created by colonies of star ascidian sea squirts seem like they have been painted onto every surface. I can’t help taking photos of each new colour scheme.

Scroll through this slideshow to see some of the different star ascidian colours…

Looking at one thing leads to another. Next to a patch of star ascidian, my friend notices an odd-looking brown blob. It is plant-like: brown, stumpy and gnarled like an old stem.

Styela clava sea squirt with star ascidian in the background – spot the flatworm!

Despite appearances, this is a distant cousin of the star ascidian. Styela clava, sometimes known as the leathery sea squirt or the clubbed tunicate, is a single animal rather than a colony of zooids. It arrived in the UK 1950s. Originally from the North West Pacific region, it is known to sometimes cause problems by growing in huge numbers on mussel farming ropes.

A movement draws my attention back to the star ascidian.

I sometimes spot the sea squirts opening and closing their siphons, but this is a larger shift. There is another squidgy animal at work here.

A flatworm is flowing across the surface of the sea squirt, moulding its body to the ridges and slopes as it goes. The worm is a fabulous midnight blue, flecked with yellow, yet it blends so perfectly with the colours of the star ascidian that I can’t make out its edges.

There are several flatworms on the sea squirt, but it is only when one ventures onto the rock that I can see it properly.

Cycloporus papillosus flatworm.

More blobby treasures abound on this shore: gem anemones, red speckled anemones, yellow-ringed sea squirts, golf ball sponges and more.

Gem anemone
Anthopleura ballii – the red-speckled anemone
Yellow-ringed sea squirt (Ciona intestinalis) with a photo-bombing brittle star.

There is never enough time to see everything before the tide returns, so I focus on looking for all my favourite squidgy creatures of all – sea slugs.

Elysia viridis, the solar powered sea slug chomping on green seaweed.

The autumn isn’t the best time of year for sea slugs, however my friend, Other Half and I are the most dedicated little gang of slug-finders you could hope to meet. With great shrieks of delight, we uncover a few in the course of our explorations.

Berthella plumula sea slug.

Slugs don’t have an especially cuddly reputation, but the Jorunna tomentosa is covered in tiny hair-like structures that make it look like a teddy bear to my eye. Even its rhinophores have a fuzzy look about them. There is a good reason for this sea slug’s appearance: all that fluffiness is perfect for hiding on the sponges that it eats.

Jorunna tomentosa – a fluffy sea slug.
Jorunna tomentosa’s rhinophores close-up… looking like teddy bear ears!

It’s clearly a good day for ‘hairy’ slugs because my next find is a bright-white fluffy sheep of a slug, the Acanthodoris Pilosa. Nudibranch slugs are a likeable bunch, but this one is especially appealing with its floofed-up gills and those towering rhinophores balancing on its head like two leaning helter-skelters.

Acanthadoris pilosa
Acanthodoris pilosa sea slug.

It won’t be long before the autumn gales rage through, bringing the darker winter days behind them. It is strange to think of these tiny squidgy things clinging on here through everything the Atlantic will throw at them. By the time the spring sunshine returns, I may be able to start leading Wildlife Watch groups again. It will be exciting to make up for lost time.

Bonus sea slug…. Polycera sp. with my fingertip for scale
Polycera sp. sea slug moving surprisingly quickly towards its bryozoan meal. The yellow speck on the right may be a second, even tinier slug.
And another squishy thing! Calvadosia campanulata stalked jellyfish.
Sponge – Aplysilla sulfurea

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

A Summer Splash with a New Friend

I know there are good reasons not to meet people you only know from the internet, but I often do. It has been brilliant every time because people who love the rock pools are the best! When an online acquaintance who is part of the Shores of South Devon group messaged me about meeting up, I knew we would have a great time.

Junior and I grabbed our beach shoes and headed to the local rocks to meet her. The tide might not have been the lowest ever, but with three keen pairs of eyes on the job and warm water (by Cornish standards) to splash around in, we couldn’t fail to have fun.

Our new friend especially wanted to see cowries and sea slugs, so we had fun looking.

The summer seaweed was starting to die back and the water was cloudy with plankton and silt, but the sun breaking through the water made it easy to see. There are always plenty of interesting molluscs; the dusky-pink cowries and chitons caught our eye.

A pretty chiton – Lepidochitona cinerea

The mid-shore pools are extensive around Looe and are crammed with rock pool species, all jostling for space and food. This cushion star was out exploring a shallow pool.

Cushion starfish in the rock pools

Anemones know their place as the star of the show! They love plankton-rich water and come in every possible colour. The brightest of the day was this gorgeous dahlia anemone.

Dahlia anemone
This daisy anemone had a fabulous purple mouth
Waving tentacles of snakelocks anemones catching the sunlight (and some plankton).

One of the great benefits of summer rockpooling is that we can go as deep as we like in the pools. Junior was excited to show our new friend his favourite swimming pool. It’s unusual to find seagrass in the rock pools, but there are usually a few clumps of it here. Sure enough, Junior spotted it straight away.

This deep pool often has some seagrass growing in it.

Our new friend was wonderfully excited by everything we saw and the time flew by as we met urchins, crabs, variegated scallops and other incredible little creatures.

A green shore urchin wearing a selection of this season’s seaweed.
A St Piran’s hermit crab pops out to say hello.

Many of the rocky overhangs and boulders were coated in animal life. Thick sponges, gelatinous sea squirts and mossy bryozoans crowded together with tube worms and spiral worms in a jumble of colours and shapes.

This distinctive sea squirt has four crimson spots at the tip of each zooid.
A collage of sponges and sea squirts.

It almost goes without saying that we were looking for sea slugs. Our friend had found a few on other beaches and was keen to discover more. There are generally fewer about on the shore at the end of the summer, when the spawning season is coming to a close, but there was still a chance of seeing some.

On a loose piece of seaweed floating in with the tide, I found the unmistakable pink spaghetti coils of sea hare spawn. Looking through my camera, I could see the developing eggs inside. These ones probably would not survive, but many others will have hatched successfully.

Pink spaghetti! Sea hare spawn.
Lots of baby sea hares developing!

As we searched among the rocks in a shallow pool, an eel slid past my feet and promptly disappeared, tunneling effortlessly down among the pebbles.

Common eel slinking away to hide under the stones.

Just when we are leaving the pools, I checked under a stone and found a nudibranch sea slug. It was a beauty with long pink cerata and striking brown rhinophores. The slug might only have been a centimetre or two long, but it was speedy; every time I thought I had it in focus, it went gliding away across the rock. It didn’t matter. We were all happy just to enjoy watching it for a minute before returning the stone exactly as we found it.

We found a sea slug! Favorinus branchialis.
The brown rhinophores with a bulge near the top are typical of Favorinus branchialis.
Favorinus branchialis. This little nudibranch likes to eat the eggs of other sea slugs.
Look closely – the shining blue dots are the eyes of tiny baby fish!

As always, it was great fun to explore the shore with someone else who takes delight in the little things. In a fast-moving world, it’s important to take the time to connect with nature and with each other.

Social media certainly has its downsides, but I love how easy it is to find others who care about the natural world and to build real-world social connections with them. If we are going to find solutions to the problems facing our environment, those connections will be essential.

Whatever the tide, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.

This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

Who Needs Mythical Beasts? Rocket Jellies, Snakelocks Anemones and a Dragonet

When my son was younger he thought he saw a kraken. I returned from releasing a crab after an event for the local Cub pack to find him and a friend staring out over the sea, shading their eyes to better spot tentacle tips or unusual splashes among the waves. They were quite sure it was out there.

I watched with them for a long time, until the tide was lapping at our boots, because you never know what might be in the sea. A giant squid would be unusual, but our oceans are full of things that are so weird we are only just beginning to understand them. We sometimes see seals, dolphins and fish feeding frenzies, so why not a kraken?

Since then, my son has grown up a lot and is less sure that there are krakens in Looe. We no longer spend much time hiding in the woods looking for dragons or watching the waves for sea serpents. Junior still loves mythology, Cornish and otherwise, but knows that the real world has as much strangeness as fiction.

We are two minutes into this week’s rock pool expedition when he calls to me urgently to look at a thing he’s found.

Junior at work!

“I think it’s a hydroid medusa,” he says, because there’s not much he doesn’t recognize these days. “Quick, it’s going to get away.”

I grab a pot and wade over to where he is pointing. Staring into the tangle of colourful seaweeds, at first I see nothing.

A flicker of movement has me scooping up the water and when I look in my pot there is a tiny creature zipping from side to side, throwing itself against the edges of the pot like a trapped Trogglehumper. Of course, this creature is not a Roald Dahl creation, but an actual, fabulous marine animal. My books call it a ‘root arm jelly’, although Junior and I know it by a different name.

Whoosh! A rocket jelly. (Cladonema radiatum – aka the root arm jelly).

“Rocket jelly!” we shriek in delight.

With great care, we transfer the jelly into the lid of the pot to see it better.

The underside of the hydroid medusa (Cladonema radiatum – the root arm jelly)

The main part of its body, measuring less than a centimetre, is a perfectly transparent dome, through which we can see its rocket shaped internal parts. Pointing downwards, a mouth fringed with ball-shaped structures is feeling about, moving left and right.

The jelly’s transparent body with dark eyespots around the edge. Root arm jelly (Cladonema radiatum).

At the base of the medusa’s dome there are several dark eyespots. Spreading out at around them, like the fire below a rocket, are the most incredible red tentacles. They are branched, curled and almost feathery. As we watch they expand and contract, feel and reach.

Every time I focus on the medusa, it fires itself off in a new direction. Zooming from one side of the petri dish to another in an instant.

I have never seen a medusa with such expanded tentacles before, but I am sure this is the same species of ‘rocket jelly’ we have seen before (Cladonema radiatum).

Those little tentacles pack a strong sting for their size; it is an efficient little predator. I always find it hard to comprehend is that this free-swimming, speedy jelly is the reproductive stage of a colonial hydroid: an organism which lives attached to rocks or seaweed and doesn’t move from the spot.

Obelia geniculata - a hydroid known as 'sea fir'.
Hydroids like this sea fir, Obelia geniculata, live attached to seaweeds.

While Junior takes photos of the rocket jelly, I notice a young fish glide over the sand, stopping near my feet. It has mottled markings in blue, orange and brown, which look colourful and yet provide the fish with an ideal camouflage among the sand, pebbles and shell fragments. Its eyes are mounted high on its head, giving it a wide field of vision. This is the wonderfully-named dragonet.

Dragonet lying still on the sand. Despite the lovely colours, it is perfectly camouflaged.

These captivating fish have a distinctive way of swimming in short bursts across the seafloor and they have an exceptionally long first dorsal fin. Male dragonets raise this sail-like fin as part of a mating dance, which I would love to see some day! It is perhaps this display, somehow reminiscent of a frill-neck lizard opening its collar, that gives these fish their fabulous name.

Dragonet saying hello to my camera!

The dragonet comes unusually close to my camera before scudding away over the sand, becoming invisible every time it stops.

I take some photos of another striking animal with a mythical name, which seems to abound in this pool: the snakelocks anemone. Just like the Medusa of Roman mythology, this anemone has long, green moving ‘hair’. Instead of being made of snakes, though, the anemone’s locks are its stinging tentacles. They are pretty but deadly, especially if you are a small animal, or even quite a big one. We’ve often seen crab legs hanging out the mouths of these large anemones.

Snakelocks anemones in the rock pool.

Some snakelocks anemones are neon green with purple tips, while others are a muted beige colour. Out of the water, they are a sorry squidgy mess of jelly but in the pools their tentacles move and flow, sometimes with the current, sometimes reaching and grabbing for prey they have sensed.

Snakelocks anemone – some are green and some are beige.

The chug of a boat makes us look up. Unusually for this area, there is a dive boat close to the rocks. Two-by-two, people in Scuba gear pop up on the surface and clamber aboard. I wonder what they have seen and whether they have noticed the tiny rocket jellies, lurking dragonets or even the medusa-haired snakelocks anemones.

Dive boat close in to shore.

Perhaps the divers have seen the kraken as they’ve explored the sea just beyond our reach. Even if they have, we don’t feel we have missed out by being confined to the land. The rock pools are full of truly magical beasts. You just have to look.

Snakelocks tentacles waving in the current.

paddle–swimming And fish-whispering: Summer rock pooling in Cornwall

The sun is back and, for once, it has coincided with some big tides. Beach shoes at the ready, Junior and I scramble across the rocks, the clamour of the busy beaches far behind us, heading for our local pools. With Covid levels higher than ever in Cornwall at the moment, we’re hiding away from the crowds as much as we can.

The view to Downderry from East Looe.

We are so used to having to put on layers, waterproofs and wellies that it feels quite decadent to be able to wander about comfortably in shorts. The water is sparkling and the sun’s reflection on my camera screen is so strong that I can’t see the image properly, even when I adjust it to maximum brightness.

I might not be able to see much at first, but the pools are full of life. We cross the rocks to a wide pool fringed with oarweed and sugar kelp. We slip and slide over thongweed and step carefully into the cool water to avoid disturbing the wildlife.

Gorgeous blue-rayed limpets are everywhere on the kelp.

A small movement reveals the presence of a well-camouflaged dragonet. Knowing how hard it is for anyone to detect it, the fish takes its time, gliding a short distance across the sand then taking a break, seeming to disappear each time it stops.

The dragonet blends in perfectly with the sand, pebbles and shells.

Among the delicate red seaweeds, there are plenty of stalked jellyfish (Haliclystus octoradiatus). Their colour range is the same as that of the seaweeds, so although they are bright and attractive, they are not easy to spot.

Stalked jellyfish: Haliclystus octoradiatus

With every step I am getting deeper into the pool, but for once it doesn’t matter. Soon I am right in the middle, with water lapping up to my waist. A blue dragonfly zigzags past me, swooping low before turning back and disappearing towards the cliff.

I wade over to a tall rocky overhang while Junior enjoys a swim across the pool. There are several large fish flitting in and out of the kelp so I lower my camera a little at a time to see how they react. When this is successful, I decide to make the very best of the summer conditions. I pull my swim goggles on and lower my head into the water.

The fish (juvenile pollock) are stand-offish at first

There is a nursery shoal of juvenile pollock down here.  They hesitate at first. Winding their slender bodies through the kelp fronds, they watch me through wide yellow-rimmed eyes.

The young pollock get ever closer to take a look at me.

I’ve always thought of pollock as a silver coloured fish, but these youngsters are golden-green with shimmering blue stripes running from their head to their tail. Their jutting bottom lip makes them look open-mouthed, mid-conversation.

Hello fish friends! The young pollock are keen to take a close look at my camera.

They are certainly a friendly bunch, swimming ever closer to the camera until their tails are brushing the lens. I have to keep lifting my head to breathe, but they don’t seem to mind.

Video: Hello fish!

After a while, I leave the pollock to talk among themselves and move on to an adjoining pool. A shoal of sand eels is patrolling here. These fish are of a more nervous disposition, turning, balling and flashing with silver at the slightest disturbance. If they spotted a predator, they would flee head-downwards, burying themselves in the sand in an instant.

Sand eel swim-past.

I move slowly and give the sand eels space, turning my attention to the sea squirts and snails on the rocks.

An especially pretty yellow star-ascidian surrounded by pink algae and red seaweeds.

When the tide turns, Junior and I retreat to the first pool, swimming and bobbing in the water, watching butterflies tumble past and swallows circling high above. There are boats, people and a whole world out there, but, like the pollock, we are happy in our rock pool refuge.

Even the seaweeds are shining in the sun. Forkweed, Looe, Cornwall.

Whatever the weather, always stay safe in the rock pools. Follow my rockpooling tips to look after yourself and the wildlife on the shore.


This website is a labour of much love and the content is available for free to everyone. My wonderful readers often ask if there is a way to support my work. You can now ‘buy me a coffee’ through my Ko-fi.uk page. (Just click donate and you can set the amount to pay by PayPal). Thank you!

For everyone who loves Cornwall's rock pools. Information about great beaches, marine wildlife and conservation.