Tag Archives: Millendreath

Meeting up and staying apart in the rock pools

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

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

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

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

Botryllus leachii colonial sea squirts

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

A cowrie on the search for sea squirts to eat.

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

Goniodoris castanea exploring the petri dish.

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

Goniodoris castanea showing off its beautiful autumnal colours.
Goniodoris castanea

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

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

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

A lurking velvet swimming crab.

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

Sea slug spawn…. now to find the slugs.

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

Polycera norvegica feeding on bryozoans.

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

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

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

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

Starfish and Blue-Rayed Limpets on a gloomy day

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

To the rock pools!

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Happy rock pooling!

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

A close (enough) encounter with Weever fish.

We’re on a stomp about the beaches between Looe and Seaton, enjoying a patch of sunshine.  “Watch out for Portuguese Man O’War jellies,” I warn Junior as we cross the muddy sand at Millendreath. I know there have been reports of them washing up all around the south west coast over the last few weeks, but there are none today. Inevitably, it’s something else that nearly gets me.

In a sandy pool at the sea’s edge, a flicker of movement catches my eye. It happens so quickly I can’t be sure there’s anything there but the sand is settling, suggesting something has just buried itself.

I call Junior over to look and I crouch low, reaching a hand to the water’s surface. If I can scoop the sand up from underneath I might be able to gently lift out the creature. Having seen plenty of well-camouflaged dragonets scooting about the pools today, I expect this to be another one. I stop short and stare into the shimmering pool.

Dragonets, especially the females, are perfectly camouflaged on sand.
Dragonets, especially the females, are perfectly camouflaged on sand.

It’s a good call. You never know what might be lurking in the rock pools. Near where I saw the movement is a sandy coloured lump. I think I recognise the shape, but it’s only when I lower my camera into the water and zoom right in that I can be sure. A Lesser weever-fish is staring down my lens, its frog-mouth gaping slightly, the rest of its body buried in the sand. Before I can take a shot it’s gone. Continue reading A close (enough) encounter with Weever fish.