YASMIN MEEDA: I have seen bioluminescence only once and it
was honestly the most magical thing that I have ever seen.
ROSIE HOLDSWORTH: It's a bucket list natural phenomenon every
traveller would love to experience. Bioluminescent tides
or sea sparkles are a rare and ethereal looking sight. And
we're heading to the ocean to meet the strange species who use
light to send signals through the dark. I'm Ranger Rosie
Holdsworth. Welcome to Wild Tales, Bioluminescent Baywatch.
You might have seen the pictures on Instagram of lagoons of
electric blues and greens. People on the shore at night
splashing in waves that look lit up as if by magic. This natural
phenomenon is called a bioluminescent tide.
So, what causes the sea to light up in this eerie way? What's it
like to experience it? And why is Bioluminescence itself found
in so many mysterious ocean creatures? To find out, we need
to go down to the ocean where it's... Dark at night or in deep
deep waters where light shows up in the pitch black.
YASMIN MEEDA: I'm Yasmin Meeda, I'm a marine biologist by
training and I'm now working as a postdoctoral researcher at
Cranfield University.
ROSIE HOLDSWORTH: Dr Yasmin Meeda who goes by Yaz is not
your typical marine biologist. You might imagine people in
Yaz's profession out in research boats, studying dolphins,
turtles, fish or other big fauna of the seas. But Yaz is
interested in something different. She specialises in a
branch of marine biology called microbiology.
YASMIN MEEDA: I deal with all the tiny hidden wonders of the
ocean that nobody really thinks about. It's often overlooked.
I'm really interested in understanding how these
microbial life actually sustain all the bigger species in the
ocean that we know and love, like whales and sharks. But we
really need to understand these tiny organisms.
ROSIE HOLDSWORTH: Yaz is usually found in her white coat in her
lab, pouring over the little guys, the weird and wonderful
hidden microscopic organisms that don't get a lot of love,
but they're essential for all ocean life.
Yaz has another great passion, to make sure science is for
everyone.
YASMIN MEEDA: I'm really trying to champion the fact that
science should be accessible to absolutely everyone. Myself, I
actually failed my A-levels when I was at school. And then
suddenly I really had a passion for science. And I believe that
you don't have to have straight A's to actually get through and
become a scientist.
ROSIE HOLDSWORTH: Yaz's drive to open up science to more people
led to her creating her Instagram account.
YASMIN MEEDA: So I post on social media with a handle
@marinebiologywithyaz. And it started just as showcasing to
family and friends what I get up to. I mainly made this page to
showcase the hidden wonders of the ocean.
ROSIE HOLDSWORTH: As a marine biologist, Yaz knows all about
bioluminescence. But she's only ever actually seen it once. And
the experience has stayed with Yaz as one of the most memorable
of her career.
YASMIN MEEDA: I have seen bioluminescence. Only once. And
it was honestly the most magical thing that I have ever seen. I'm
an ambassador for the Marine Stewardship Council in the UK.
We were fishing for sardines using ring net fishing. So this
is a way to reduce bycatch so you're only fishing for what you
want.
I was fortunate enough to go out on a sardine fishing boat in
Newlyn in Cornwall and I've never been on a fishing boat and
as a marine biologist I'm always in the lab. I'm hardly ever out
at sea so this was a really new experience for me. So we set off
at around 8pm in the evening. And I was told it should be
quite calm. It should be OK. But we're going out at night and
we'll be back early hours of the morning.
So there's me, never been even fishing before. And so I'm now
on this fishing vessel that we're going out. We're going out
quite far into the ocean. And I'm like, wow, there's nothing
around me. It's pitch black. I could see the stars. I could see
the milky way.
I've never even seen that so vivid because obviously with
light pollution, you can't see it. And as we were fishing, once
they'd deployed the net, this is when I saw so many birds just
coming down. And there were loads of seabirds, some
seagulls, other species of birds I didn't even know. And it was
so loud.
The noise was just immense. And then as I was looking at these
birds, I could see that they had these specks or these sparkles
of a greeny blue hue. And I was like, this looks interesting.
And then one of the fishermen was like, it's the phosphorus.
It's the phosphorus.
ROSIE HOLDSWORTH: Phosphorus is a chemical element that can
sometimes glow in the dark. But Yaz knows what they're seeing is
something different.
YASMIN MEEDA: And I was like, what are you on about? And they
were like, that's what we call it, the phosphorus. And I was
like, no, I think that's bioluminescence. And they were
like, oh, is that what it's called? And I said, yeah, I've
never seen it in real life. I've only ever seen videos. The
colour was definitely like a bluey-green. You only see
bioluminescence when there's movement in the water.
So as the waves are crashing and the birds are diving into the
water, you then get this kind of different shades of this
bioluminescence coming up and it's brighter in some areas and
it's dimmer in others. And honestly it was just like an
alien world to me because we were the only vessel I could see
for a while. We were in the middle of the ocean I couldn't
even see land and yet all around me were just these birds and
bioluminescence and it was incredible.
ROSIE HOLDSWORTH: ROSIE HOLDSWORTH: Bioluminescent
tides occur all around the world and some of the best known spots
include beaches in Australia, Thailand, Puerto Rico and
California. These sea sparkles also appear here in the UK.
Wales has some of the most famous bioluminescent tides and
it's found in other places too, like Yaz's experience in
Cornwall.
What you see in photos and videos can look a little
different to with the naked eye, though no less magical to
witness.
YASMIN MEEDA: But I think what people see on photos or on
documentaries can be slightly over-exaggerated. This is a
little bit similar to my experience with the northern
lights. I think your camera can really overexpose the green hue.
You could definitely see it. And it was more like a, almost a
neon green.
ROSIE HOLDSWORTH: We know bioluminescent tides look
magical, but what exactly is happening? Bioluminescence, when
an organism lights up from inside its body through a
chemical reaction, is found in nature in certain species. In
the case of tides like those Yaz saw, these are caused by a type
of algae called dinoflagellates.
In these dinoflagellates, bioluminescent light is created
when two chemicals, luciferin and luciferase, interact with
oxygen. This chemical reaction is triggered when water
containing the dinoflagellates is disturbed, like when waves
crash on the shore or when birds dive into the sea to catch fish.
YASMIN MEEDA: Bioluminescence happens in loads of different
organisms but in the ocean it is typically from dinoflagellates
which are a group of phytoplankton and they are
microscopic so you can't see them with the naked eye you'd
need a microscope to see them normally. But when they create
this bioluminescence you can see it as light and that's because
there are thousands of them so collectively you'll be able to
see this light.
ROSIE HOLDSWORTH: ROSIE HOLDSWORTH: Bioluminescent
light isn't just found in these tiny dinoflagellates. It's found
in lots of species, occasionally on land but by far most
widespread in the ocean.
YASMIN MEEDA: Fireflies are a really good example of
bioluminescence and so they cause bioluminescence within
themselves but I've never actually seen fireflies myself.
The anglerfish that are found in the deep sea, I want to say ugly
but maybe that's unfair. They're the ones that if you've seen
Finding Nemo, it's got the big light on the end of its head.
And the bacteria that are within these anglerfish are responsible
for the Bioluminescence that you see. So that's how they can see
in the dark when they're in the really deep sea.
For different species, there could be different reasons as to
why they have bioluminescence. Sometimes it could be because of
mating. So it could attract a mate. Or for the case of
dinoflagellates in the ocean, it could be to deter a predator.
And then that will deter the predator because they'll think,
oh, there's something there and it will scare them off, which I
think is pretty cool.
ROSIE HOLDSWORTH: And perhaps the most mysterious is the
centuries-old story of milky seas. Sailors talked of an eerie
phenomenon of looking out to the ocean at night and seeing it
transformed, as if blowing ghostly white all the way to the
horizon.
In the 1990s, scientists looking at satellite images finally
confirmed these milky seas were a type of Bioluminescence, this
time caused by bacteria, and that the light could be seen all
the way from space.
Bioluminescent tides like in Yaz's story are relatively rare
but they occur often enough for you to have a chance of
witnessing them. So what are the top tips for seeing them for
yourself?
YASMIN MEEDA: My top tips if you want to see bioluminescence
would definitely be to look out on the coast. There are certain
areas within the UK that you could see it such as in Wales
I'd definitely say Cornwall is a really good spot.
My experience was not from the shore so I don't know how
prominent it will be if you're just watching from a beach and
want to go and hunt for it. But if you can get on a boat and go
and explore I think definitely looking at either Facebook
groups or looking online at different travel blogs or
Instagram or TikTok I think you could definitely find it and
spot it from there.
ROSIE HOLDSWORTH: I've seen bioluminescence myself just one
time, on land. In glowworms' shining green bums in Leeds. It
was really, really magical. But I've never seen bioluminescent
tides in the ocean. They're really high on my bucket list.
The fact this phenomenon even exists reminds us that our world
is still so full of mystery and wonder.
YASMIN MEEDA: I think the fact that bioluminescence is really
unique is something that I think is quite alien to the world. And
for me, I think that's one of the most amazing things about
evolution and just the natural world, is that these things have
just sprung up in nature based on either it could attract a
mate, it could deter predators.
And so I just think it's absolutely incredible that
different organisms have such different traits that help them
survive in our planet.
ROSIE HOLDSWORTH: If you'd like to look for bioluminescence for
yourself, do search for groups dedicated to spotting it along
the Welsh coast and other parts of the UK. Just please don't do
anything daft and follow safety advice when you're mixing with
water, tides and the dark.
Summer is a great time to see the UK's glowworms. You can find
out more about them in our episode show notes. Until next
time, follow Wild Tales on your podcast app. Find us on
Instagram @wildtalesnt. And share your stories with us with
#wildtaleswednesday. See you next time.