After we've all come back from a sunny day on the beach and are thinking about going to bed, Thomas Winstone might just be heading out there and if you want to spot him, he's probably the one glowing blue.

Thomas, 42, is an astrophotographer and you'll sometimes find him out at the seaside long after the sun has disappeared for the day to catch a very special, almost magical sight.

“I wanted to take a selfie in front of some waves at Caswell Bay. The waves were probably about three feet tall, so quite big waves to be fair, and the whole wave from top to bottom just glowed blue,” he said.

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He decided to stand in front of the wave to try and capture his silhouette against the light.

“I was doing that photo and it worked quite well, so I thought, ‘well, I’m in waist-deep now, big waves crashing, I’ll go for a swim in it.’ I swam through it and I was just absolutely amazed. Seeing my hands doing front crawl, seeing my hands going into the water, lighting up blue as they go along my side before coming back out and going back in again.

“I noticed on the surface of the water tiny little fish, and as I’m swimming they’re trying to swim away from me. As they do so, they light up as well. It was just absolutely crazy. I stood up and it was dripping off my skin, just glowing blue as it was dripping off. It was insane."

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The blue glow is called bioluminescence - caused by plankton - and is usually only found in the tropics. However, if you head to your local beach when it’s dark enough, you might be lucky enough to see it for yourself.

Bioluminescence describes the light that some living creatures, such as fireflies and jellyfish, emit from their cells. The sight is so special that there are now social media groups for those wanting to find the plankton for themselves, and Thomas is part of one of them.

The bioluminescent plankton appearing at Caswell Bay

The plankton glow due to a self-defence mechanism, when they are agitated by the movement of the water, and Thomas said one of the best places in Wales for astro-photography was the south Wales coast due to the lack of light pollution. These are the top 10 beaches in Wales according to the Sunday Times.

“That then leads on to spending many hours at beaches and things like that. That’s when we picked up on the plankton really. You see a blue glow and you think, ‘Is it a head torch, is it a boat?’ and you ask a few people what it might be and that’s when we discovered the plankton.”

Heading out onto the beaches of south Wales in the pitch black has allowed Thomas, from Brynmawr, to discover all sorts of incredible sights.

“Recently, at Aberavon, there was a dolphin swimming around and it was glowing blue,” he said.

“It was lighting up blue, just swimming through the plankton. It is absolutely amazing and that’s what drives me to see it because, you know, it’s a relatively small opportunity to see it. It’s just a passion because you never know what you’re going to see. You could have the best display ever, wildlife attracting it - all sorts. It’s just amazing.”

Bioluminescent plankton at Caswell Bay, Gower, Swansea on June 9

Thomas said his best trip to see the plankton was about three years ago when he found himself glowing blue after his swim.

“To get this in Wales is so special. You could go to Jamaica, India, Thailand, South Australia to go and see it, where it’s more guaranteed. But to have this on our doorstep, in the middle of a pandemic when you can’t really travel, or travelling has got more expensive, it’s a cracking way to promote Wales for tourism and things like that as well.”

“At the moment, the best area seems to be the south coast around the Gower,” Thomas said. However, he recommended that people explore their local coastal areas to see the plankton and avoid disappointment after travelling for long journeys.

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Thomas also said the summer months were usually the best time to see the plankton.

“It’s almost a given now, it seems to be. I don’t know whether it’s to do with a rise in sea temperatures over the years, and things like that, but the summer months definitely seem to be better,” he said.

“It has been documented as late as October, maybe even November, but that’s extremely rare.”

Thomas said that, despite theories about the plankton appearing depending on tide times and phases of the moon, he had seen the plankton at both low and high tide.

“The same can be said about the moon - I’ve photographed it on a full moon, when it’s a half moon, or no moon. It’s a bit vague, it’s hard to pinpoint in that respect,” he said.

He said the advice he’d offer to those who wanted to go out in search of plankton was to be considerate to other people, and to avoid shining torches, once safe to do so, as they would hide the effect of the plankton glowing.

“Try to get somewhere dark and keep it dark,” he said.

Thomas also said he tended to walk backwards on the beach as this allowed him to see his footprints sparkle and glow - an indication the plankton in the sea, as well as on the sand, was at the point where it was ready to glow.

Lee McGrath, 46, works as a theatres commodities coordinator at Neath Port Talbot Hospital, but also ventures out to capture the bioluminescence along the Welsh coast.

“A few years back a story popped up that the bioluminescence had been seen on the Welsh coast. Me and a fellow photographer started actively looking for it as we would be at the beach anyway doing astrophotography,” he said.

Lee McGrath said he would constantly check local beaches for the plankton
The plankton give off bioluminescence as a self-defence mechanism
The plankton have been spotted around the Welsh coast, including at Aberavon

Lee, based in Bridgend, said he and his friend, based in Swansea, would constantly check their local beaches for the plankton.

“I normally shoot places that are out of the ordinary so the plankton fits perfectly with my type of photography,” he said.

“In 2018, me and a friend were alone at Aberavon where there was a display at the pier that was otherworldly. The only thing I can compare it to are the Northern Lights when I was in Iceland. It is very addictive once you see it.”

Lee first saw the plankton at Three Cliffs Bay on the Gower, and said it was an “amazing” experience.

“It is like something otherworldly, once you get your eye in to spot it, you know what to look for,” he said.

He said the best time to see the plankton was when it got dark during the summer months, as the temperature warmed up. In terms of where to find the plankton, Lee said that was “the big question.”

“We are lucky to have seen it the last few years on the Welsh coast here, you just have to put yourself in these locations and hope for the best.”

Lee McGrath: "It is very addictive once you see it”
People swimming in bioluminescent plankton at Aberavon

Lee encouraged those wanting to see the plankton to be patient due to its unpredictability. He said people could increase their chances of seeing it by putting in time and being at the locations where the plankton had been spotted after dark. He also recommended turning off torches and to be wary of tide times and your position on the beach at night to avoid being caught by the water coming in.

“I have been out 10 plus times this year and not seen a single thing. It is all about commitment and a bit of luck - right place, right time,” he said.

Tim Bow, 39, a programmer and keen astrophotographer, came across the bioluminescent plankton while trying to photograph the Milky Way one night in 2018.

“I saw it first of all when we had that really strong pulse back in 2018, and every year since I’ve been keeping an eye out for it,” he said.

“This year, myself and a friend were the first people to see it back at the start of June, and that’s pretty much started the craze this year. I’ve seen even more people this year going out looking for it.”

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Tim said he thought he’d seen the plankton at Three Cliffs Bay this year, but was unsure until he saw the bioluminescence later on his photographs.

“I went to Caswell the following week to shoot the Milky Way, and it was just myself and my friend. It was really strong, but any time you see it it’s amazing. I don’t know how you’d describe it - it’s quite an ethereal experience,” he added.

Tim said the experience could feel “intense” when you were not expecting to come across the plankton.

“It’s so bizarre when you see it, because it’s like electric pulses through the water. I imagine a lot of people don’t see it the same way, because we all see colour differently. When I see it, it looks like this green-blue colour, and it’s just really intense.”

Tim said his parents told him he’d seen the plankton when he was younger in Florida, but he didn't remember the experience. He said it was best to go somewhere “as dark as possible” for the most powerful effect of the bioluminescence. However, he encouraged people to remain safe when venturing out onto the beach at night.

“A lot of people are going down to Newton and Porthcawl, and when the tide is low, there’s sinking sand there, which is quite dangerous,” Tim said.

“Don’t get disappointed - rather than asking where or what time is the best place to go, just think of a beach and go there because you can’t plan it. People are asking, ‘is it going to be there in three weeks?’ but you don’t even know if it’s going to be there the day after.”

Diti Kumar, 26, photographed the plankton for the first time at Penmon Lighthouse

Diti Kumar, 26, is an international student at Bangor University studying an MSc in accounting and banking. She recently saw and captured photographs of the plankton for the first time.

She is a member of two Facebook groups dedicated to tracking and photographing the plankton. Diti saw that, in mid-June, the plankton had been spotted near Penmon Lighthouse

“I was very excited as this location is very close to Bangor and there was the possibility that I could see this happen one day in person,” she said.

Diti Kumar: "It was completely magical - I would say the photos do not do it justice"
The plankton has been spotted as late as October and November

“I started keeping an eye on the app with the tides forecast. I researched about the plankton, and it said that if there’s a warmer temperature, there are more chances that you will get to see the plankton."

After going out to see the plankton twice, Diti said there was no sign of them, but on a third visit in July the weather was “perfect.”

“We got lucky and we saw it happening. It was very prominent to see it all happening on the shore and in the waves. It was completely magical - I would say the photos do not do it justice. If you see it in person, it’s completely radiant,” she said.

“I’ve lived all my life in cities, so this was my first time experiencing something in the countryside, and I would say it was a once in a lifetime opportunity for me. The light show looked almost extraterrestrial - I don’t know how to explain it. It looked like there were stars in the sea that you could touch.”

The best time to see the plankton is late at night or in the early hours of the morning

Diti advised those who were keen to see the plankton for themselves to keep an eye on Facebook groups to see where they had been spotted, as well as keeping an eye on the temperature of the water. She also recommended setting your phone camera to a specific setting to best capture the plankton.

“We used two phones - one was the Samsung Galaxy L21, and the other one was the iPhone 12 Pro. We put the settings to non-exposure settings, for 10 seconds in night mode. That was the most important setting to capture that light,” she said.

Where is the best place to see the plankton?

It is impossible to predict where the plankton will be on a given night, so people are discouraged from making long journeys to see the plankton at a specific location. However, Thomas Winstone recommended that people go out to their local coastline to see if they could spot it there. Patience is recommended.

What time is best to see it?

The best time to see the plankton is when it is dark. The plankton are usually spotted during astronomical twilight, which is between 11pm and 3:30am in the UK for June and July. However, Thomas said he had spotted the plankton as early as 10.20pm previously.

How long will it be around for?

It is difficult to tell. The plankton are often spotted in the summer months, however the phenomenon has been spotted until as late as October and November.

What are the best conditions to spot the plankton?

While there is no concrete answer for this, the plankton appear to favour warm sea temperatures and clear, sunny days. However, the bioluminescence has also been spotted in heavy rain and thick fog.

What to look for

The plankton will appear as a faint glow, but can appear stronger on some nights where the blue neon glow can be seen from as far as 100-200m away as the waves break or as you agitate the water by splashing or throwing in a pebble. It is recommended that you turn off your torch in order to better see it once you have reached a safe place to do so.

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