Category Archives: Fish

Birthday Rock Pooling

It’s that time of year again. Amazing spring tides, ideal conditions and, of course, it coincides with Other Half’s birthday. Lucky him! What else could he possibly want to do but come rock pooling? To be fair, he needs no persuading that it beats a day in the office and, as a birthday treat, I offer him an evening out afterwards – watching me give a talk at the Cornwall Marine Recorders’ event in Gwithian (with a bar and nibbles).

We pile into the car ridiculously early in the morning to make sure we make it to Prisk Cove in time to meet our lovely friends and their twins to explore as the tide rolls out.

This beach is a little off the beaten track, but worth the walk. We find it empty of people and the tide so far out that the kelp hangs limply in shallow pockets of water in the bay.

The beach’s sheltered position between the Helford and Falmouth Bay, combined with the huge numbers of loose boulders, makes this habitat perfect for many marine species. Despite his initial certainty that he won’t find anything, Junior’s friend is first to find a spiny starfish. Its long tapering arms set with thick spines have an attractive purple hue.

Spiny starfish at Prisk Cove near Falmouth
Spiny starfish at Prisk Cove near Falmouth

We watch its many tentacle feet reaching out to explore the rocks.

Spiny starfish arm in action
Spiny starfish arm in action

The asymmetric heads of flat fish always intrigue me, so I am delighted when we find the first little topknot, then more and more of them. Some are sticking to the rocks, even clinging on when completely upside down, using their fringing fins to mould themselves to bumps and imperfections in the surface. Their mottled patterns can make them hard to spot and they stay completely still to avoid detection.

Topknot flatfish resting on a rock
Topknot flatfish resting on a rock
Flatfish like this topknot have their mouth set on one side of their head.
Flatfish like this topknot have their mouth set on one side of their head.

Under a large rock we find a large edible crab that makes the other twin shriek. She soon overcomes her nerves when I move it out of the way so that we can look at the fish, which are also sheltering here.

Everyone crowds round to see the stunning colours and impressive headgear of the tompot blenny, and the kids are amazed by the smoothness of the rockling’s eel-like skin.

Tompot blenny
Tompot blenny

Other Half holds the edible crab for a quick birthday photo before we pop everything back where we found it.

Edible crab at Prisk Cove
Edible crab at Prisk Cove

Out among the furthest accessible rocks, the twins’ mum is not being outdone. She brings some fish over to show me, among them a beautiful goldsinny wrasse. It’s not a fish I often see on the shore, but it is easily identified by its two dark spots, one at the front of its dorsal fin and the other at the top of its tail.

Goldsinny wrasse at Prisk Cove
Goldsinny wrasse at Prisk Cove

It has wide orange eyes with a flash of blue and the wonderful pouting lips of the wrasse family.

Goldsinny wrasse - a beautifully coloured fish
Goldsinny wrasse – a beautifully coloured fish

The finds flood in and I struggle to keep up with taking photos of everything to ensure that I can submit records afterwards. On one area of the shore I find a large patch of Wakame.

This invasive non-native seaweed is easily identified by its corrugated-looking stipe and thin, floppy fronds. Originating from China, Japan and Korea, it has spread widely in Europe and can out-compete native seaweeds.

White painted top shells, an improbably hairy purse sponge and an interesting anemone all catch my eye before the tide turns.

An especialy hairy purse sponge - presumably just a variant of Sycon ciliatum
An especialy hairy purse sponge – presumably just a variant of Sycon ciliatum
Painted top shells are usually pink, but this beach had many of the white variety
Painted top shells are usually pink, but this beach had many of the white variety

I also discover half a dozen shark eggcases of the Greater spotted catshark (Scyliorhinus stellaris) attached to the rainbow wrack of the lower shore pools.

Catshark egg case among the seaweed
Catshark egg case among the seaweed
When it is in the water, Rainbow wrack is wonderfully iridescent
When it is in the water, Rainbow wrack is wonderfully iridescent

All too soon it seems, the tide is flowing in. At first it is a faint current, but it turns quickly into a churning river through the tight gullies and we retreat to enjoy a birthday picnic.

A lovely little Lamellaria snail, likely Lamellaria latens
A lovely little Lamellaria snail, likely Lamellaria latens
Limacia clavigera sea slug at Prisk Cove
Limacia clavigera sea slug at Prisk Cove
An especially small anemone growing on rainbow wrack.
An especially small anemone growing on rainbow wrack.

A summer of snorkels, jellyfish and wrasse

On a summer’s day when the sea and the sky are a matching blue and the whole world sparkles, there’s nothing as inviting as donning a snorkel and taking a swim across the bay. This summer, for the first time, Junior joined me in my forays over the rocky reefs.

While he built up experience, we floated shoulder to shoulder and sculled our way over the waving seaweed to the deeper gullies.

On our third snorkel outing, I was enjoying the sun on my back and the gentle roll of the waves when Junior screamed down his snorkel. I grabbed his arm in case he was hurt, but he was frantically pointing and making the “fish’”sign with his hand. He had just seen his first ballan wrasse.

The fish was a full-sized adult, maybe 40 or 50cm long with a thick body and a criss-cross patterns of lines interspersed with pale blue spots. An impressive fish. Undeterred by Junior’s shriek of excitement, it carried on its slow, hovering path through the kelp-lined gully for a while before darting away as we neared.

Juvenile ballan wrasse can be bright green like this one, but they grow up to around 50cm long when they're mature.
Juvenile ballan wrasse can be bright green like this one, but they grow up to around 50cm long when they’re mature.

On the same venture, we spotted barnacles feeding with their feathery legs, shore crabs strolling along the sea floor, a shanny surveying its territory from the top of a rock and great glistening shoals of sand eels rolling by. On other days, we came across groups of corkwing wrasse with pouting lips and turquoise-striped faces, spider crabs lurching through the kelp, and tangled snakelocks anemones spreading their green tentacles.

Snakelocks anemone
Snakelocks anemone

Nearby, crowds of tourists paddled and swam, oblivious to the beauty below them (or the pinching claws and stinging tentacles near their feet).

This summer has seen waves of jellyfish drifting through, from comb jellies to the harmless moon jelly, the less harmless blue and compass jellies and the enormous barrel jellies. Some days the sea was thick with jellyfish, but this didn’t stop Junior from mastering the art of catching waves on his bodyboard or wiping out headfirst into the blue-jelly-soup. He swam for the shore in a hurry on one of our snorkel safaris though, when a compass jelly brushed over my face and stung my back.

Compass jellies have striking markings and also pack a nettle-like sting
Compass jellies have striking markings and also pack a nettle-like sting

I have almost no photos of our snorkelling expeditions this year. Next year, when Junior is more confident, I’ll be able to carry a camera, but this season we just revelled in the perfect days and soaked up the sun . As we knew it would, the summer ended abruptly, dissipating like a mirage from one day to the next and the water is no longer so inviting.

For now, we are hanging up our snorkels and returning to the rock pools, exchanging beach shoes for wellies as the autumn chill moves in, but there is everything to look forward to. A week of Shoresearch surveys starts tomorrow in Looe, which is guaranteed to bring new finds and lots of species records for Cornwall Wildlife Trust.

The empty beaches make this a wonderful time of year to explore the rock pools and before we know it, the first of the autumn storms will blast in, washing who knows what onto our shores. Watch this space!

Between the snorkel trips, I did squeeze in some rock pooling. Here are some of my favourite photos from the summer.

Xantho hydrophilus crab
Xantho hydrophilus crab
Candy striped flatworm grazing on bryozoans in Looe
Candy striped flatworm grazing on bryozoans in Looe
A variegated scallop with irridescent shining eyes
A variegated scallop with irridescent shining eyes
A green shore urchin with its tentacle feet extended
A green shore urchin with its tentacle feet extended
Doris ocelligera sea slug - I recorded these for the first time a couple of months ago and have found them regularly in the same spot this summer.
Doris ocelligera sea slug – I recorded these for the first time a couple of months ago and have found them regularly in the same spot this summer.
St Piran's hermit crab - now a common find on all our local beaches.
St Piran’s hermit crab – now a common find on all our local beaches.

Friendly Fish at Kynance Cove

A day at Kynance Cove on the Lizard Peninsula has become a fixture in the Cornish Rock Pools calendar. The smooth, serpentine cliffs don’t create many hiding places for marine life, but Junior loves the geology and caves. There are always creatures to see too if you look carefully enough, so I take the opportunity to relax in the sun, staring at fish through the clear water.

There’s one pool in particular that I like to visit here. It is more like an aquarium than any other I’ve found; just deep enough to house a whole community of small blennies and always buzzing with life.

Watching fish at Kynance Cove with Junior (photo by Other Half)
Watching fish at Kynance Cove with Junior (photo by Other Half)

The funny thing is that, while I stare in, the fish stare back, creeping closer up the sides, over pink encrusting algae and through fronds of the Corallina seaweed to secure a better view. Bold young shannies, prop themselves up on their two-pronged pectoral fins, swivelling their colourful clown eyes to observe me.

Being watched... a young shanny (common blenny) edges up the side of the pool to take a look at me. Kynance Cove, Lizard, Cornwall.
Being watched… a young shanny (common blenny) edges up the side of the pool to take a look at me. Kynance Cove, Lizard, Cornwall.

In the far corner of the pool, a Montagu’s blenny pops up to say hello. It’s easily recognisable by its pronged head tentacle, which looks like a tiny Christmas tree.

If you’d like to know how to identify rock pool fish, take a look at ‘What Fish Have I Found?’

The Montagu's blenny almost gets out of the water to take a look at me. Kynance Cove, Cornwall.
The Montagu’s blenny almost gets out of the water to take a look at me. Kynance Cove, Cornwall.

The surrounding rocks are covered in barnacles, which suits these fish well. The Montagu’s blenny likes nothing better than to nibble the feeding legs off barnacles.

I soon start to doubt that this fish is just curious. Unlike the shannies, which are just juveniles, this Montagu’s blenny is full size and sports a fine pattern of turquoise spots on his body. It is the male blenny’s job to guard the eggs, and this fish is taking no prisoners.

This bold Montagu's blenny has striking blue spots and a dark stripe through its eye.
This bold Montagu’s blenny has striking blue spots and a dark stripe through its eye.

He seems determined to chase me out of his territory, repeatedly headbutting my camera. He may only be 7cm long, but I have a feeling that if I put a finger in the water he won’t hesitate to take me on with his sharp little teeth.

Blennies' thick lips make them look like they're smiling, but this Montagu's blenny just wants to attack my camera!
Blennies’ thick lips make them look like they’re smiling, but this Montagu’s blenny just wants to attack my camera!

The hard rock becomes uncomfortable to lie on after a while, digging into my legs, but I try not to change position. The fish will scatter if I make any sudden movement or noise. Half a dozen shannies are darting around the bottom of the pool, while others are basking in shallow grooves at the edge. The Montagu’s blenny doesn’t take his eye off my camera.

I watch him until the tide turns and the waves begin to sweep in. This may not be the most diverse rock pooling beach, but the fish are a joy to watch and it’s a wonderful spot to while away a sunny morning before enjoying a pasty in the café. Summer starts here!

Kynance Cove - always a hit!
Kynance Cove – always a hit!

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.

Giants of the Cornish rock pools

Last week I shared with you the miniature world of the sea slugs, so this week I’ll super-size things and bring you some big fish. Silly-season reports of Great-white sharks often hit the headlines in Cornwall, but I prefer rock-pool giants; they’re not made up, and you can get close to them without having your leg bitten off!

Cornwall is brilliant in all sorts of ways, our network of local, grassroots marine conservation groups being just one of them. The public launch, last week, of the new Three Bays Wildlife Group brought experts and volunteers together and gave me a chance to explore some new beaches in the St Austell area.

Judging by the squeals of excitement from the children and adults alike, the crabs, pipefish, prawns and anemones we found at the main rockpool ramble on Portmellon beach near Mevagissey went down well. By the end of the day, the local group had recruited lots of potential new volunteers.

Green shore urchin at Portmellon beach - adorned in seaweed
Green shore urchin adorned in seaweed. Portmellon beach.

Continue reading Giants of the Cornish rock pools

Wrasse and wrack

The Cornish summers are anything but predictable. One day I’m sweltering in shorts and beach shoes and the next I’m shivering in waders and a thick jumper. Although the showers are back with a vengeance, there’s always something to be found if I can make it across the rocks without breaking an ankle.

Painted top shell, East Looe
Painted top shell, East Looe

My first outing is to the rocks beyond East Looe beach and I’m pleased to come across a new colony of St Piran’s hermit crabs on the mid-shore.

A St Piran's hermit crab starting to emerge from its shell.
A St Piran’s hermit crab starting to emerge from its shell.

They’re becoming a familiar sight around Cornwall and I’m starting to recognise them from the tips of their red legs, before their chequerboard eyes and equal-sized claws emerge from their shells. Continue reading Wrasse and wrack

A predator among the fish eggs: Calma gobioophaga sea slug

If you read this blog regularly, you’ve probably noticed a pattern: I bimble about the Cornish rock pools looking for an exciting creature, fail completely, then find something unexpected. Well, hopefully you like the format because this week is no exception. I go on a quest to find fish eggs and discover this rare sea slug.

Continue reading A predator among the fish eggs: Calma gobioophaga sea slug