Category Archives: Wildlife

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!

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.
Dragonet

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!

Neap Tide Adventures

Days like this don’t seem ideal for rock pooling; the tide is nowhere near low enough to expose my favourite pools and the weather is iffy. Despite this, I am convinced that there is plenty to see on the mid-shore. Cameras and rock pooling super-crew (Other Half and Junior) at the ready, we set out to uncover marine treasures.

One advantage of neap tides, when the sea doesn’t go out very far, is that it won’t rush back in either. We can take our time. Junior soon locates lots of gem anemones with their tentacles wide open.

Gem anemone

Under a stone further down the shore, I spot a beautifully camouflaged anemone. It’s too small to see properly, so I have to wait until I get home to confirm that it’s a Sagartia troglodytes anemone.

Sagartia trogladytes anemone

The B shape at the base of the tentacles is a useful identifying feature, although I’ve always thought they look more like Scooby Doo ghost eyes than letters.

Other Half calls me over to look at a blob. He’s becoming quite an expert blob finder.

We look together at the tiny brown jelly-spot on the seaweed. At first, we think it is an anemone because it seems to have a circle of retracted tentacles. As soon as I dunk it in the water though, I can see the pale lumps of primary tentacles around the edge. It must be a stalked jellyfish.

Is it just me or does this stalked jelly not look pleased to see me? Haliclystus octoradiatus.

Gradually, the stalked jelly unfurls each arm until it looks much less blob-like.

Haliclystus octoradiatus -starting to look more like a stalked jellyfish than a blob.

The rain seems to be holding off now, and I make myself comfortable by a calm pool to watch the little world go by. My camera has barely entered the water before a bold prawn trots out of the seaweed, its legs working at top speed in its eagerness to check out what I’m up to.

Common prawn coming to take a look at my camera.
Common prawn

A head pops up between the fronds of saw wrack at the back of the pool. The young Montagu’s blenny swivels an eye back and forth beneath its jaunty headgear. I feel a larger blenny move through the seaweed near my hand and lift my camera out of the water before I get a nip from the territorial shanny.

Peek-a-boo! Montagu’s blenny taking a look above the serrated wrack.
Montagu’s blenny.

A dinky starfish in the coral weed catches my eye. I see several species of starfish on this beach, but this is a mid-shore specialist: Asterina phylactica. The colours of the tiny pincers on its back (the pedicellariae) form an orange star shape. Under the camera, I can see its tube feet reaching out and exploring its surroundings as it glides along.

Asterina phylactica – cushion starfish

Other Half brings passes me a tiny shell he has found. He thinks it might be a wentletrap, a shell we sometimes find. I have never seen one so small and assume it is probably a different species. I take a look with the camera and realise he was right. The bold sculpture of ribs over the rounded whorls of the long spire are striking, even in this tiny juvenile. Best of all, the shell is occupied.

Juvenile wentletrap

I watch the snail emerge and set off across the pool.

This makes me think of a unicorn and a rainbow – juvenile wentletrap.

Sea squirts are something of an enigma to me. They are hugely varied in their colours, shapes and sizes. Aplidium turbinatum, in particular, seems to me to look different every time I find it. When I first see this one, I am convinced that the white, spiky-looking set of openings under the coral weed is a bryozoan.

I know this looks familiar, but takes me a long time to work out that it is Aplidium turbinatum, a sea squirt.

Yet, after a while watching it, I realise it is opening and closing like a squirt, puffing water in and out. It bears little resemblance to the orange gelatinous Aplidium turbinatum I usually see further down this beach, but the jutting triangular crowns around the edge of each opening are the same.

Aplidium turbinatum sea squirts

Fortunately, I can turn to the incredible Aphotomarine website for confirmation and, sure enough, it has some photos of very similar specimens (thanks David!).

While the tide seeps back into the pools, we chat with a fellow rock pooler whose photos I have often seen online, and who I eventually realise I have met before in real life through another conservation group.

Chthamalus sp barnacles starting to open as the tide comes in.

By the time we leave, the sun is low in the sky. I am more than satisfied with all the wonderful creatures I have found on the neap tide, and it is high time I had some birthday cake.

Strawberry anemone

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

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A Swim Over The Rock Pools

“Quick, I need the camera. There’s a jelly.”

Junior’s enthusiasm takes me aback. He has a healthy aversion to getting close to jellyfish. We have already changed course many times on today’s high tide swim to avoid the trailing tentacles of compass jellyfish.

Compass jellyfish. Also known as sea nettles as they pack quite a little sting, these jellyfish have beautiful markings.
The distinctive markings of the compass jellyfish.

These common summer visitors have striking brown V-shaped markings around their edges, like the points of a compass. Although their sting is rarely serious, somewhere in the region of a stinging nettle in strength, it isn’t much fun if you swim face-first into one as I have done on a few occasions.

Crystal jelly. This is a hydroid medusa rather than a ‘true’ jellyfish. It has short tentacles around the edges rather than long trailing tentacles.

Some other species we have seen this week, like the moon jellyfish and crystal jellyfish, are harmless but today only the compass jellies are out.

One of many moon jellyfish washed up by the strong swell. This species is harmless.
Moon jellyfish only have a very weak sting so are usually harmless to people. Never touch a jelly if you’re not sure of the species and wash your hands well before touching your eyes.

Incredible numbers of sand eels fill the water in every direction, flashing silver as they turn, before melding into the green sea. Junior notices a small spotted catshark (Scyliorhinus canicula) – also known as dogfish – swimming through a rocky gully beneath us. Alongside submerged rocks, several species of wrasse flit among the kelp.

This sand eel is speeding along – photo by Junior

I unclip the camera from the safety float and pass it to Junior who is pointing excitedly at something I can’t see.

I dip under the water and look at where he’s pointing. Still nothing. I bob up for air and try again.

This time I see something much smaller than I was expecting, or half see it – it’s mostly transparent with just the faintest pink hue.

Comb jelly – photo by Junior

“Is it a comb jelly?” Junior asks. This is the first one he’s seen and much excitement ensues as he tries to photograph a barely visible tiny swimming thing while holding his breath and floating in water 5 metres deep.

Comb jelly by Junior. The transparency of the animal and its movement in the water make it hard to focus, but you can see the shining light of the combs.

Mostly we just enjoy the incredible coloured light show this Beroe cucumis comb jelly is putting on for us. The iridescent disco-light effect is created by lines of beating hair-like cilia (the combs) that run the length of the comb jelly’s body.

This species looks like a simple hollow tube or sack, but it is an efficient predator, known to feed on other comb jellies.

The different colours of the lights around the edges of the comb jelly are incredible to watch. Photo by Junior.

How Junior spotted this little speck in the ocean, I have no idea. We look around for more but find none.

Comb jelly by Junior.

Eventually we have to head back to shore, drifting over all of our familiar rock pools on the way. Hermit crabs and netted dog whelks are out in force and as we near the beach, we see shannies basking on sunny rocks in the shallows.

There are lots of these ‘south clawed’ hermit crabs (Diogenes pugilator) on the sand. Their left claw is much longer and larger than their right.

This might not be rock pooling in the usual sense, swimming on a high tide gives us a whole new perspective on life here. You don’t need to be a billionaire to become weightless and take a soundless flight over the rock pools. There is no better way to see how this environment looks for most of each day, when the wider ocean and the shore cross over and become one.

Swimming in the sea in Cornwall is a wonderful experience but is very different from swimming in a pool and can be dangerous. Always consider the conditions and stay well within your limits. Check the weather, tides and currents, enter the water slowly and adjust to the temperature. Choose a lifeguarded beach if possible and a place where you know how to safely enter and exit the water. Swim alongside the shore. A tow float makes you more visible and beach shoes can protect you from weever fish and sharp rocks. Don’t swim alone and let someone know where you are. In any emergency at sea or on the shore, call the Coastguard on 999.

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 Night Out In The Rock Pools

It’s not often that you have the beach to yourself in Cornwall in July, but we want to show our friends the best Kernow has to offer. With this in mind, we meet Irys and her mum late in the evening to walk to our local shore and crunch across the sand to the rocks in the grey twilight.

Arriving at the empty beach before it is completely dark. (Photo by Other Half).

It doesn’t seem dark yet, but the birds are quiet, there are no other people about and it’s becoming hard to see where we’re putting our feet.

At night, it is especially important to put safety first so that you don’t find yourself in difficulty and have to get the Coastguard out of bed. We stick to a planned route on a beach we know well so that we will not be clambering over unfamiliar or slippery rocks. As always, an outgoing tide is safest and we arrive a full two hours before low tide so that we will leave before it turns. Sturdy boots and good torches are essential equipment, as are working phones and warm clothes. Our best-loved pieces of nighttime kit are our ultra-violet torches. Irys is trying hers out for the first time.

Testing the UV torch on some anemones. (Photo by Other Half)

The lack of predatory birds and drying sun makes life easier for rock pool inhabitants, so most of them are nocturnal. Creatures that we have to search for in daylight, such as prawns, crabs and fish, are all out and about looking for food.

Junior takes Irys straight to his favourite spot for seeing gem anemones. Under the UV torch they glow brightly, as does this snakelocks anemone. This fluorescence is caused by proteins that may help the anemone to survive in bright sunlight in shallow pools.

Snakelocks anemones

By scanning the torch across the pools it is possible to spot the anemones from some distance away.

Snakelocks anemones fluorescing. Seaweeds on the rock are also fluorescing red and pink.

We stand on the rocks and look into a large pool. Prawns, glowing blue under the UV torch, swim to and fro, intent on feeding. A common shrimp skitters across the sand. The green seaweeds glow bright red and the pink encrusting seaweed takes on a deeper pink-purple hue.

Exploring the pools as it gets dark.

We alternate between the normal torches and UV, finding sea scorpion fish, a rockling and even a young tompot blenny with its distinctive headgear. Irys finds a common blenny in a hole in the rock, lying still and breathing through its skin while it waits for the tide to return.

Sea scorpion fish – Taurus bubalis – hiding among the seaweed.

Hermit crabs run around the pools and some of the top shells glow pink under UV where their shell has worn away to reveal the mother of pearl layer below.

Taking a close look at an isopod at night. (Photo by Other Half).

Flying insects swarm around our head torches while bats dance in and out of the light. We tread carefully and stop still for long periods, looking into the water, enjoying the window into the animals’ lives while the waves splash against the rocks beyond us.

It’s fascinating to explore fluorescence. Anemones glow, stalked jellyfish not so much. Crabs and isopods stand out against the seaweeds in shades of blue and grey. A shell containing a hermit crab shines a bright orangey-red, probably due to micro-algae growing on it. In every pool, once you get your eye in, there are countless blue specks zipping about in dizzying circles, which must be copepods or similar small crustaceans that I would normally only see under the microscope.

At night, crabs often emerge from the water and cross the rocks. This green shore crab was carrying a limpet off to eat.

Green shore crab holding a limpet in its right pincer.

Normally it is the rising tide that brings an end to our rockpooling, but tonight it is tiredness that creeps up on us. Still buzzing from all that we have seen, we head home to bed. Behind us the rock pools seem quiet and deserted, but we know better; for the wildlife on the beach, the night is just beginning.

Cushion Starfish and Babies Galore – Summer Rockpooling in Looe.

The sun is shining, the tide is going out and I’m wearing my ‘new’ blue sunglasses that I found in a rock pool last week. Junior and I are searching for signs of new life on the sheltered shore at Looe. Most of all, we are looking for cushion starfish eggs.

We aren’t the only ones out on the beach. Grey herons, egrets, oystercatchers, great black-backed gulls and crows, many with hungry nestlings to feed, are taking a keen interest in the pools and rocks. We give the birds plenty of space and settle ourselves by a mid-shore pool.

There is always lots going on here. Colonies of light-bulb sea squirts are sprouting up around the rocks, hermit crabs scuttle across the gravel and prawns swim over to see what we are doing – or perhaps to see if we are edible.

Light bulb sea squirts.

Under a rock adorned with a brilliant blue patch of Terpios fugax sponge, a rock goby is lying still, watching me through small eyes.

Terpios fugax – a blue sponge
Goby

Another goby close by, its head poking out from under a stone. There is no sign of any rock goby eggs, but as I check the underside of the rock, something glides along its surface.

Spot the fish

It’s hard to see what the tiny creature is. It looks as though it is changing colour as it moves, but this is because I am seeing straight through its body to the colours of the algae and sponges. After a few attempts, I manage to zoom in on the baby fish, which rests only for a few seconds at a time before zipping forward in a new direction.

The baby fish is very transparent.

This is probably a baby goby. As the summer goes on, many quiet mid-shore pools will hold large populations of tiny gobies and blennies.

The juvenile fish’s organs and spine can be seen clearly in its transparent body.

The cushion star Asterina gibbosa is a common rock pool starfish here in Cornwall, easily recognized by its puffy body and short, stiff, arms. These little starfish all start life as males and then become hermaphrodites (with both male and female organs) as they grow.

Unlike many other species of starfish, these cushion stars do not spawn into the plankton but lay a clutch of bright orange eggs. I sometimes find newly-laid eggs several times.

Cushion stars (Asterina gibbosa) laying eggs

When the eggs are developing, the curled-up legs of a baby starfish can just be seen.

Developing cushion star eggs.

This area of the beach seems to be a popular egg-laying site for the cushion starfish, so today I am hoping to fully developed or just-hatched eggs.

I search the pool, gently lifting a few stones before replacing them exactly as they were. This pool is crowded with St Piran’s and common hermit crabs of all sizes. The high population means that there is competition for shells. One St Piran’s hermit crab is occupying a very battered dog-whelk shell with half of the back missing – it’s better than nothing.

St Piran’s hermit crab in a broken dog whelk shell.

A Xantho hydrophilus crab wanders past me. From the way her tail sticks out a little behind her shell, I can see that she must be carrying eggs. I take a quick look, keeping her in the water and cradling her to keep her eggs safe. The tiny black spots on the eggs show that they are near hatching. Under my camera I can see all the little eyes staring out.

Xantho hydrophilus crab – female with eggs. The feathery accessories around her tail keep the eggs in place.

When her eggs are ready to hatch, the crab will release them into the sea, flapping her tail to send them on their way. The baby crabs will swim in the plankton for a while before gradually changing into their final form and settling.

Xantho hydrophilus crab eggs looking ready to hatch

Finally, I come across a small patch of orange cushion star eggs under a rock. I crouch down and put my camera in the water. These eggs look a little different to others I have found. It takes me a moment to realise why: they have hatched!

Instead of eggs, I am looking at hundreds of minuscule orange cushion stars, all very gradually extending their little tube feet and beginning to move and explore.

The cushion starfish eggs have hatched. Asterina gibbosa juveniles.

Most of the cushion starfish babies are still piled up together in a huddle, but some are a few centimetres away from the crowd, already taking their first journey alone in the rock pool.

I am entranced. So much so, that I don’t notice that I am sitting in the water getting a wet bottom while I take photos. I could stay watching this forever, but I want to share it with Junior.

A bundle of newly-hatched baby cushion stars.

Junior goes through the same process as me, seeing the eggs and taking a few shots on his camera before realising what he is looking at. He’s seen most things in the rock pools by now so it takes something special to impress him. This is something very special.

Newly-hatched cushion starfish.

Cushion stars are lovely; baby cushion stars are pure magic. Once again, the rock pools have exceeded all our expectations. We will never know how things turn out for these particular baby starfish, but we may well meet some of them again as adults on our future visits to our local shore.

If you are visiting the beach this summer, be sure to rock pool responsibly and safely. Check the tides and leave everything as you found it. Read my top tips for successful rock pooling.

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!

Dotty Doto Sea Slugs (and an ode to a spade)

My son has had the same spade since he was three. When I first agreed to let him loose with something bigger than himself with sharp metal on the end it was something of a risk. Since then, it has been his favourite possession, enjoying frenzied use on beaches all around the Cornwall and in all weathers, creating dams, pits, castles and ‘sand volcanoes’. The blade has been wobbling for some time now, but today Junior has plans for a tide fort at Millendreath, so we hope for the best.

Blue spade going strong in 2019 (age 8).

We cross the rocks towards the sandy beach, stopping on the way to explore the pools. Many of the seaweeds growing at the base of the rocks are covered in a dense thicket of Dynamena pumila hydroids.

Dynamena pumila hydroids (the yellow strands) on seaweed.

They look like pale plant stalks, each just a few centimetres long, but up close I can that each ‘stalk’ is made of a stack of downward-pointing triangle shapes.

Dynamena pumila up close – looking like a stack of tiny golden cups.

When they are submerged as the tide comes in, a circlet of delicate stinging tentacles will emerge from each side of every triangle to catch passing food. Hydroids are fascinating animals, and are also a favourite food of some other species, including sea slugs.

Among the hydroids are a few spots of jelly, just a few milimetres long. They are very hard to see, especially while the seaweed is stranded out of the water, but these are sea slugs. In places I find the hydroid stalks are entangled with a fine strand of white – the sea slug spawn.

A tiny Doto sea slug out of water – my fingertip is in the background for scale.

I try various ways to get the hydroids into water so that I can see the slugs better, but nothing works. I don’t want to harm any of the animals by removing them so I give up.

Trying and failing to take good photos of a Doto sea slug in situ.

Further down the beach towards the sea, the gulls are making a huge racket, screaming and splashing. Where the rocky gully we are in opens into a wide sandy pool, we come upon a scene of complete chaos. Scores of herring gulls and some greater black-backed gulls are jostling for space: some swimming on the pool, others flying down and yet more perched on the rocks all around. Many are dunking their heads in the water, reaching for something. There must be food here.

We try not to bother them but most of the birds fly up as we clamber over the last rocks to the beach. I take a quick look in the pool and find it is strewn with dead sand eels. There are so many that they have drifted into heaps against the rocks and some have tangled themselves into balls in their efforts to escape.

It’s sad to see so many dead sand eels but, for the gulls and other seabirds, it is a bonanza.

These mass strandings of sand eels happen sometimes. Perhaps it is the warm weather and low tide combining to starve them of oxygen as they hide in the sand, or perhaps a large shoal became trapped here and were an easy target for the seabirds. There is nothing to do but leave the gulls to their feasting.

There were hundreds of dead sand eels in this pool.

While Junior is shoveling sand with his dad, I return to the hydroids. After much searching, I find a slug that is only loosely attached to its prey and manage to wash it into a small tub. As soon as it is in the water, it transforms from a featureless blob into a magnificent structure of wobbling towers and waving rhinophores.

Doto sp. These slugs look magnificent in the water.

This is a Doto sea slug, but the species is not so clear. Most Doto slugs feed on very specific hydroids. My old books suggest Doto coronata can feed on Dynamena, but now it seems that they eat other things and that this is likely a different species, perhaps Doto onusta. Whatever it’s called, it is a true leader in the field of jelly architecture.

I have no idea what purpose the towering protrusions topped with dark spots fulfill – maybe camouflage, maybe just housing to its digestive organs, but they are incredible.

Doto sp. sea slug.

I find a sheltered pool where I can photograph and watch the little Doto for a while, before gently returning it to the exact same place I found it.

The dotty Doto slug exploring the pool.

Junior has just about finished his sand fort when his spade finally parts from the handle with a wet crunch. We lovingly assemble all the bits and make sure to pack them into our bags, hoping that we can somehow repair it later. We share stories of all the happy times Junior has enjoyed with his spade over the course of the last nine years. It feels like saying goodbye to a family member, but the tide is coming in and Junior perks up to defend his fort from the waves, standing atop the sand until the sea starts to flood his wellies.

Back at home, Other Half disappears into the garage and rummages for a while before emerging with the spade firmly fixed to a new shaft. Blue spade lives to build again!

Other finds…

Common periwinkle
Cowrie
Stalked jellyfish (Haliclystus octoradiatus)
Spider crab (Macropodia sp.)