Issue 2025.04

Revealing
the Invisible

↑ Catalonia, Spain One of the species I’ve worked with the most, due to the complexity of their flight, is the starling. After sunset, these birds usually gather to roost, whether in cities or wetlands, and in this case, a reed bed. When a falcon appeared at that moment, the starlings reacted with this hypnotic and extraordinarily complex flight that leaves no one unmoved.

The Art of Making Flight Visible

Words and Images by Xavi Bou

Since I was a child, I’ve been fascinated by the sky, not just by the clouds or the changing light, but by the living choreography that unfolds above us. Sometimes chaotic, sometimes perfectly synchronized, bird flight has always held my attention.

Over time, that fascination grew into a need to understand and reveal what we cannot usually see.

That’s how the “Ornithographies” was born, a project built around a simple question: What shape does a bird’s flight take? Not a single frame frozen in time, but the full trajectory of movement. To answer this, I use a technique inspired by 19th-century chronophotography, adapted to the digital tools of today. I film with high-resolution video cameras that record in slow motion, using the best equipment available to me at each moment. From those recordings, I extract hundreds or thousands of frames and merge them using an algorithm I developed. The algorithm isolates and overlays the bird’s motion, preserving the background untouched. This is how “Ornithographies” emerged, a name drawn from the Greek: ornis, bird, and graphia, drawing.

**Catalonia, Spain** Homing pigeons are particularly good at orienting themselves and returning to the place they were raised. People train them by taking them to increasingly distant locations in specialized trucks. This image captures the moment just after they’ve been released, when they circle in the sky to get their bearings. It has been shown that pigeons can perceive the Earth’s magnetic north, and that’s exactly what they’re doing here: flying in circles to figure out where they need to go.

With this project, I didn’t just want to show the beauty of flight; I wanted to connect with something deeper. In recent years, many studies have highlighted how birdwatching can benefit mental health. Looking up, following the flight path of a common urban species like a blackbird or wood pigeon, becomes a form of mindfulness. Ornithology, even in its most everyday form, helps us be present, disconnect from a frenetic pace, and reconnect with the here and now, and most importantly, nature.

**Grand Teton National Park, Wyoming, USA** Barn swallows are a common sight in the Grand Tetons and are known for their ability to catch insects in flight. These barn swallows take advantage of the last hours of the day — when many insects fly over Jackson Lake — to make erratic flights in search of food. A single barn swallow can eat about one insect every minute or up to 850 insects per day.

By making the invisible visible, “Ornithographies” strengthens that bond. It encourages us to pay attention to what surrounds us and rediscover what we take for granted. We don’t need to go far to find wonder — just look up. The sight of an ordinary city flock, through this lens, becomes a window into animal behavior and a renewed awareness of our relationship with nature. This approach, rooted in the everyday and the familiar, is an invitation to value what we have and protect what remains.

This realization was the moment a new world opened for me. My job became curating the most interesting choreographies of birds and revealing them, from the ripple of a gull’s wings frozen into airborne waves to vultures spiraling on thermal currents like ribbons in a whirlpool.

**Jökulsárlón, Iceland** The apparent chaos in the sky is caused by a feeding frenzy. Arctic terns are diving to catch sardines, and in the middle of this activity, two parasitic jaegers are trying to steal the sardines directly from the terns’ beaks. This kind of aerial chase is a typical example of the intense and dynamic interactions that take place in this rich ecosystem.

One of the species that has impacted me most is the swift. These birds live almost entirely in the air — they eat, sleep, and even mate in flight. They rarely land. Capturing their traces in the sky feels like following the signature of an artist who never touches the canvas. Their flight is fast, curving, and erratic, producing hypnotically complex visuals. I’m always amazed by their aerial life.

**Catalonia, Spain** Starlings perform their characteristic flocking behavior, known as a murmuration, while under attack by two peregrine falcons. The starlings form a dense defensive cloud while a ribbon-like shape captures the interaction between the two falcons just after an attack.

Starlings offer another unique spectacle. Their murmurations of vast flocks undulating at dusk form patterns that resemble fluid waves. It’s a defensive behavior, but also a form of natural art, as no two formations are alike. The images born from these flights evoke clouds, smoke, art, and even imagined architectures.

**Hálsanefshellir, Iceland** On this well-known beach in southern Iceland, strong and sudden waves are infamous, claiming the lives of unwary tourists every year. Just a few meters away, seabirds like puffins and Northern fulmars nest on the cliffs. They spend all day flying back and forth out to sea to feed their chicks. The result is a sky full of movement, especially striking on this stormy day.

Crows fascinate me for different reasons. Known for their intelligence, they fly with a certain freedom, gliding, diving, and performing aerial acrobatics. I’ve watched them play in thermal updrafts, shifting direction without purpose, as if they simply enjoy the act of flying. When translated into images, their paths become spontaneous dances that are full of energy.

**Gallocanta, Spain** Gallocanta is a well-known place where tens of thousands of common cranes from northern Europe spend the winter. It’s the largest inland natural lagoon in Spain. The cranes gather here to find safety and security through the night. During the day, they disperse in small groups in search of food in the surrounding fields.

I see my work as that of a curator searching for these fleeting aerial choreographies that usually go unnoticed and giving them form. In many ways, my work bridges science and art. I collaborate with ornithologists to better understand the species I photograph. I hope my images spark wonder but also raise questions: What kind of bird is this? Why does it fly like that? How does its environment shape its movement?

The goal of my art is clear: to foster an emotional connection with nature. When we learn to observe, a sense of empathy arises, even one that can inspire action. Not everyone will become an activist or a scientist, but all of us can be allies in conservation if we develop a personal bond with the natural world.

xavi bou birds traveling in air a flight of birds traveling in the air multi-layer photo capture trails with mountain — **Catalonia, Spain** A rock in the Medes Islands, a small archipelago of limestone located off the Catalan coast. This marine natural park is very special, especially for its underwater biodiversity, but also in the air — it provides an ideal place for birds to nest. Both gulls and, in this case, alpine swifts, take advantage of the rock cavities for nesting. Swifts are highly aerodynamic birds that feed on insects while flying, which explains the large numbers and the unpredictable aerial patterns they draw in the sky around the limestone cliffs.

a flight of birds traveling in the air multi-layer photo capture trails — **Catalonia, Spain** Common swifts fly over the city of Barcelona. This species is one of the most extraordinary examples of adaptation to aerial life: Outside the breeding season, they spend virtually their entire lives in flight, even sleeping on the wing. Their airborne existence gives rise to a wide range of fascinating behaviors, from high-speed chases and agile hunting flights to the collection of nesting material, all performed mid-air. Capturing these acrobatics and wingbeats was essential for this work.

In my most recent project, Fluctus, I focus on another element of beauty in birds. This time to explore not their trajectories but their morphology and coloration. I photograph birds at the very moment of takeoff, from a top-down perspective and at life size. This allows us to see their structure in unprecedented detail: the symmetry, the patterns, the anatomical features that make each unique. The work involves close collaboration with ornithologists and wildlife rescue centers, adding an ethical dimension to the project.

Both projects, though distinct, share the same purpose: to discover new ways of observing and to celebrate the biodiversity that surrounds us.

After all these years, I’ve come to realize that what I’m really doing is building a kind of contemporary catalogue of curiosities and an archive of natural movements that often go unnoticed. Each image becomes part of this visual collection, not to highlight the rare or exotic, but to reveal the wonder of the familiar.

**Catalonia, Spain** Every September, large flocks of swallows and similar species like the common house martin migrate through the Ebre Delta on their way to Africa. While migration is usually gradual, some years bring extraordinary gatherings of thousands upon thousands of birds, taking advantage of the insect-rich wetlands to feed and rest. As evening approaches, they begin to gather, preparing to roost together in the reed beds for safety. This image captures that magical moment before they settle, when the sky fills with swallows in motion at sunset.

Along this journey, I’ve learned that technology, when used thoughtfully, can help us perceive what is usually unnoticed. But what shifts our understanding isn’t the tool. It’s the way we see. What changes perception is not the algorithm but the intention behind our gaze.

To those just beginning or considering a similar path, my advice is simple. Choose a subject you’re passionate about, research it deeply, and find your perspective. It’s not about the best gear or faraway locations. It’s about being present, observing carefully, and having the patience to tell a story honestly.

**Barcelona, Spain** Five yellow-legged gulls, flying parallel to the coast of Barcelona just before dawn. While the pattern their flight takes might look like strands of DNA, these undulating forms revealed in the sky are nothing more than birds flapping their wings.

I hope that this work encourages others to look up, pause, and discover that even the ordinary is filled with beauty and complexity. Because every species matters, every flight is unique, and every image can be the beginning of a new way to see and protect our planet.

See more of Xavi Bou’s work at www.xavibou.com.

The Art of Making Flight Visible

2025.04

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