The red-orange bell pulses gently, and behind it a whole universe of the finest tentacles unfolds. They interweave in the water, fan out, and gather again into a single stream. The jellyfish seems at once a living being, an underwater flower, and a comet whose luminous trail dissolves in the cold waves of the ocean.
It has no bones, no heart, and no centralized brain. Yet its body maintains a remarkable coherence, responding to light, to the movement of the water, and to the touch of the surrounding world. Each thread of the tentacles makes its own movements, but never loses its connection to the whole organism.
Before us is Cyanea capillata — the lion's mane jellyfish, one of the largest and longest jellyfish on the planet. Its maximum dimensions are astonishing: the bell can reach two meters in diameter, and the tentacles more than thirty meters in length.
An Encounter off the Coast of Wales
A 21-year-old freediver and marine conservationist Iestyn Morgan was swimming near Trefin beach on the northern coast of Pembrokeshire in Wales in September 2026.
At first he noticed tentacles stretching into the distance. There were more and more of them: three became ten, then twenty. Morgan followed along them and realized that what lay before him was not a compass jellyfish, as he had initially thought, but a large lion's mane jellyfish.
By his visual estimate, the total length of the animal together with its trailing train could have been from 10 to 15 meters — roughly the length of a bus or a small train. This is not the result of an instrumental measurement, so the exact size of the specimen remains unknown. But the video recording clearly shows the scale and complexity of this creature, which is difficult to convey fully in words.
For Morgan, this was his first encounter with such a species in the waters of Wales. Later he called it one of the most memorable events of his life. The encounter falls into that rare category of moments when a person manages to see something truly unusual in Earth's seas.
But instead of approaching the jellyfish or trying to touch it, the freediver kept his distance and allowed the animal to continue on its way. Thus the camera became not an instrument of intrusion, but a way of bearing witness to the encounter — modest and respectful.
The Lion's Mane of the Ocean
The jellyfish's name is linked to its numerous long tentacles, which surround the bell like a thick lion's mane. The Latin name, "capillata," literally means "hairy."
The animal's color changes with age, reflecting its life journey. Young individuals often have a light orange or golden hue, and with age they begin to darken, becoming purple, dark red, or brownish-violet. The largest specimens, dwelling in the cold Arctic waters, are distinguished by a particularly dark coloration.
The bell of an adult jellyfish is divided into eight noticeable lobes and resembles a star or a blossoming flower. From it extend groups of thin tentacles — 70–150 in each lobe, which in total can yield more than a thousand threads. Each tentacle is armed with stinging cells — nematocysts. They help the jellyfish capture zooplankton, small fish, and other jellyfish.
Historically, specimens of truly legendary size have been described. The largest reliably measured specimen was discovered off the coast of Massachusetts in 1865: its bell was 210 centimeters in diameter, and its tentacles reached 36,6 meters — longer than a blue whale. Yet such records are rare, and the accuracy of old measurements sometimes raises questions.
And yet, even without record-breaking figures, the "lion's mane" remains one of the most impressive forms of oceanic life. Its grandeur is revealed not only in its size. It manifests in the way thousands of delicate parts of the body move together without losing their connection to the whole.
How to move without resisting the water
The jellyfish pulses its bell, pushing out water and creating a faint jet propulsion. But for most of its long journey it travels with the currents, like a wise being that understands there is no point in struggling against the force carrying you along your way.
This is not complete passivity. The animal is capable of changing the position of its body, orienting itself in the water, and responding to surrounding conditions. Yet the jellyfish does not try to conquer the ocean. Its movement is born in the interaction of its own pulsation and the force of the current.
It sets an impulse — the water continues it. The bell contracts — the body moves forward. It opens — and the long train once again finds space. Each tentacle follows its own trajectory, but remains part of a single organism.
Within this movement there is no visible conductor directing each thread separately. Coherence arises from the structure of the body, from signals transmitted through a distributed nervous net, and from constant contact with the water. The jellyfish is not separate from the medium through which it moves. The current becomes part of its way of existing.
Life without a familiar control centre
Jellyfish have no brain in the human sense — not a single species, including the lion's mane, does. Instead, a nervous net is distributed throughout the body, allowing them to perceive changes in the environment and coordinate the movements of their organs.
Along the edge of the bell are sensitive structures — rhopalia. There are usually eight of them, corresponding to the number of lobes of the bell. They participate in perceiving light, the position of the body in space, and the direction of movement, serving as the jellyfish's senses.
This is a different organization of the living — radically unlike anything to which humans have grown accustomed over millions of years of evolution.
Humans imagine control as a vertical: there is a central organ that receives information, makes a decision and directs the remaining parts of the system. The jellyfish offers a different architecture — fully distributed and democratic.
No single point is the sole owner of the entire process. Coherence arises from the structure of the body, from signals transmitted through a distributed nervous net, and from constant contact with the water. It is like an orchestra without a conductor, where every musician hears the others and plays in unison.
This does not mean that the jellyfish possesses consciousness similar to the human kind. Science has no grounds for such a conclusion. But its existence expands the very idea of how different the forms of perception and organization of life on this planet can be.
An invisible world among the tentacles
The train of a large jellyfish is not empty space but an entire ecosystem. Small fish, shrimps and other organisms may linger beside its bell and between its tentacles. For some, this structure becomes a temporary refuge from predators; for others, a hunting territory or a source of food.
The jellyfish itself is also part of a larger food web. Despite its powerful stinging cells, it becomes prey for sea turtles, large fish and seabirds. The leatherback sea turtle gratefully eats these jellyfish, feeling almost no pain from the nematocysts.
Therefore, before us is not a separate object drifting in empty water, but a moving node of a multitude of relationships and dependencies.
Each contraction of the bell moves the water. The tentacles interact with plankton and fish. The currents carry the animal along the coast. Other creatures use the space it creates. The life of the jellyfish continues not only within its transparent body. It manifests in the entire system of connections that moves together with it.
What this encounter says about a changing ocean
The "lion's mane" prefers the cold waters of the northern Atlantic and Pacific Oceans, as well as the waters around the Arctic. It is often found in the North Sea, the Irish Sea and the English Channel, especially in the colder regions and in the waters of Scandinavia.
The appearance of a large specimen off the coast of Wales, although unusual for the observer himself, does not serve as proof of the species' relocation. A single encounter is not enough to draw conclusions about long-term climate change or the migration of populations.
The distribution of jellyfish depends on a multitude of factors: temperature, salinity, food availability, stage of the life cycle, winds and sea currents. Understanding long-term changes requires many years of systematic observations and data on water temperature.
At the same time, the opposite is also true: the ocean really is changing. Marine heatwaves and the shifting of temperature boundaries affect the distribution of many species. That is precisely why such video recordings are important not only for their beauty. Every encounter becomes a fragment of a large, moving picture of change.
Where does the animal appear? At what time of year? What size is it? Which currents and what water temperature accompanied the sighting? The answers to these questions make it possible to gradually see the changes that are imperceptible on the scale of a single day or a single year, but evident on the scale of decades.
Beauty that should not be touched
The tentacles of the "lion's mane" contain nematocysts — stinging cells with venomous secretions. Contact with them can cause acute pain, burning and skin irritation. According to marine biologists, this is the most powerful sting among all the jellyfish of Great Britain, although it is not fatal to humans.
Detached tentacles, even those dried out on the shore, retain the ability to sting for several hours. Scientists recommend not touching them with your hands and rinsing off the remains of the tentacles with warm water rather than vinegar.
That is why it is better to admire such a jellyfish from a distance — without trying to come closer, to touch it or to swim through the trail of its tentacles.
Iestyn Morgan did exactly that. He did not detain the animal or change the direction of its movement. The man entered the space of the encounter, saw a miracle — and allowed it to continue without interference. He filmed the video not in order to possess that moment, but to bear witness to it, to tell other people about the beauty of the depths of the sea.
Perhaps this is one of the most respectful forms of acquaintance with the wild.
Not to take. Not to appropriate. Not to force it to come closer. Simply to be nearby at the moment when the ocean decided to show one of its most incredible forms.
What did the living comet of the ocean remind us of?
That wholeness does not always look like motionless completeness. Sometimes it consists of hundreds or thousands of the finest threads, each of which moves in its own way. They bend, diverge and follow the water, but remain a single being.
The jellyfish does not fight the current and does not disappear within it. It preserves its own pulsation, allowing the ocean to become part of the movement. It dances with the water, not against it.
In this interaction it is impossible to draw an exact boundary between the animal and the surrounding space. The water passes through the body, carries it and responds to every contraction of the bell. The jellyfish moves in the ocean — and at the same time the ocean itself becomes visible through its movement, through its forms.
Perhaps that is precisely why an encounter with it seems like something more than merely observing a rare creature. For a few moments the person saw not a separate jellyfish swimming in the water, but a single living stream that had taken the form of a golden-red comet moving between worlds.
And with this encounter the ocean reminded us: to be in the Flow does not mean to lose yourself. It means allowing the whole space to move together with you, to find harmony between your own will and the force that carries you.
