Rome at midnight. The Colosseum is dark, the fountains have thinned to a murmur, and the tourists are asleep. But the rooftops are not quiet. Across the terracotta tiles, yellow-legged gulls are calling. A long, rising wail from a chimney pot on Via del Corso. An answer from a rooftop aerial near the Pantheon. A rapid chuckling alarm from somewhere above Trastevere. The conversation runs for hours, peaking around one or two in the morning before it finally dies down.
Anyone who has slept with a window open in a Mediterranean city knows this chorus. It sounds chaotic, even random. It is neither.
A Dutch ethologist named Niko Tinbergen spent decades decoding this language. His work helped earn a Nobel Prize. He found that gulls operate with a structured vocabulary of calls, each tied to a specific body posture and social context. What sounds like screaming is closer to a conversation with grammar.
Tinbergen’s Gulls
Nikolaas Tinbergen grew up in The Hague, close enough to the coast to watch herring gulls as a boy. He became one of the founders of ethology, the scientific study of animal behavior in natural settings, and spent decades observing gull colonies on the Dutch and British coasts.
His book The Herring Gull’s World, published in 1953, remains one of the most detailed studies of any bird species ever written. Tinbergen himself considered it his best work. The book documented gull behavior with a patience and precision that transformed how scientists understood animal communication. Where his colleague Konrad Lorenz built bold theories, Tinbergen designed careful experiments.
In 1973, Tinbergen shared the Nobel Prize in Physiology or Medicine with Lorenz and Karl von Frisch. The committee cited their discoveries concerning “the organization and elicitation of individual and social behavior patterns.” Von Frisch had decoded the honeybee waggle dance. Lorenz had described imprinting in geese. Tinbergen had mapped the behavioral world of the gull.
One of his most famous experiments involved a red spot. Herring gull chicks peck at a red mark on the parent’s lower bill to trigger food regurgitation. Tinbergen tested this by presenting chicks with painted wooden models: different colors, different shapes, different spot placements. The chicks responded to the red spot regardless of the model’s overall shape. The behavior was innate, not learned. He called it a fixed action pattern triggered by a sign stimulus, a concept that became foundational in behavioral science.
Before his scientific career took off, Tinbergen wrote a children’s book about a herring gull called Kleew in 1947. The story followed a gull chick’s first year of life, and Tinbergen illustrated it himself with watercolors.
In 1963, Tinbergen published a paper that outlined four questions every study of animal behavior should address: What is its function? What causes it? How does it develop over the animal’s lifetime? What is its evolutionary history? These four questions, still known as Tinbergen’s four questions, remain the standard framework in ethology and behavioral ecology. Every gull call described below can be examined through all four lenses.
The Vocabulary
Gull communication operates through a system of at least five well-documented call types. Each call comes paired with a specific body posture, and the posture is as much a part of the message as the sound. Hear a gull without seeing it and you get half the sentence.
The Long Call is the most complex vocalization in the gull repertoire. The bird begins with its head lowered toward the ground, then throws its neck upward at roughly a 45-degree angle while producing a series of escalating shrieks. The whole sequence lasts several seconds and grows louder and higher in pitch as the head rises. Gulls typically produce long calls after winning a territorial skirmish, when displacing another bird from a perch, or in response to aerial predators like eagles. The long call is, in Nathan Pieplow’s words, “the most elaborate, variable, and individualized call” in the repertoire. Each bird’s version is acoustically distinct enough to serve as a personal signature. Neighboring gulls learn to recognize each other’s long calls, and strangers’ calls provoke stronger territorial responses than familiar ones.
The Mew Call is simpler: a single, drawn-out rising note delivered with an arched neck. It functions as the gull’s all-purpose contact call. Adults mew when approaching the nest, when calling chicks to feed, during courtship, and even in low-level aggressive encounters. It means something close to “I’m here” or “pay attention,” and its meaning shifts with context. Crows use a similar system of context-dependent calls with over twenty variations. For more on how corvids structure their vocal communication, see The Language of Crows: What Their Calls Mean, How They Signal.
The Alarm Call starts as a soft chuckling: “ha-ha-ha-ha.” If the threat increases, the chuckling accelerates and sharpens into a “yeow.” If the threat is immediate, the call becomes a piercing “keow.” The speed and pitch of the alarm call encode the severity of the danger. A distant fox gets a slow chuckle. A swooping falcon gets a rapid-fire shriek. Other gulls nearby calibrate their response to the urgency they hear. The system works like a sliding scale rather than a binary on-off alarm.
The Choking Call sounds like a repeated “huoh-huoh-huoh” and comes with a distinctive posture: the bird leans forward, lowers its head nearly to the ground, and heaves its body upward with each syllable. It appears during courtship displays, territorial confrontations, and nest site selection. Two birds facing each other and choking simultaneously is a common sight on breeding colonies.
The Chick Begging Call, a high “klee-ew,” is the first vocalization a gull produces. It begins before the chick hatches, audible from inside the egg. After hatching, the chick uses it constantly to solicit food. Adults have their own version, a softer, quieter “baby talk” that they use during courtship or when mates return to shared nest duty. The presence of an infantile call in adult courtship behavior is not unique to gulls, but it is one of the clearest examples in birds.
Pieplow, an ornithologist who has studied gull sounds extensively, noted that gull vocalizations are “variable between individuals of the same species, plastic from the same bird, and underexplored” in scientific literature. The behavioral context, he argued, is essential: the same acoustic signal can carry different meanings depending on posture, location, and social situation.
Why They Scream at Night
The gulls on Rome’s rooftops are yellow-legged gulls, Larus michahellis, the dominant large gull of the Mediterranean basin. They breed from Portugal to Turkey, across the islands, and along the North African coast. Their natural nesting habitat is rocky sea cliffs and uninhabited islands.
Roman apartment buildings, from the gull’s perspective, are cliffs.
The colonization of Italian cities by yellow-legged gulls is well documented. The birds find flat rooftops, ledges, and chimney stacks suitable for nesting. Food comes from garbage, outdoor dining, markets, and the Tiber. The urban population has grown steadily for decades. In Venice, the first roof-nesting pair was recorded in 2000. By the mid-2000s, there were dozens. Rome’s population is larger and older.
During Italy’s 2020 COVID lockdown, with tourists gone and outdoor food scarce, Rome’s yellow-legged gulls shifted their diet dramatically. They began hunting rats and rock pigeons in the empty streets, behavior rarely observed before the pandemic.
The midnight chorus has several overlapping causes. Breeding season, which runs from March through July, drives the most intense nocturnal calling. Chicks beg for food around the clock. Adults defend nest sites against real and perceived intruders, and a cat on a nearby rooftop or an owl passing overhead triggers alarm calls that cascade through the colony. Territorial disputes between neighboring pairs flare up at night as easily as during the day.
Urban noise also plays a role. Gulls on natural cliffs call at volumes calibrated for wind and wave noise. Gulls on city rooftops compete with traffic, air conditioning units, and each other’s echoes bouncing off concrete walls. The result is louder calling, and louder calling triggers louder responses from neighbors.
Reduced visibility matters too. During the day, gulls rely on visual signals as much as vocal ones: body postures, wing positions, head angles. At night, those visual cues disappear. The vocal channel has to carry the full load. More information travels through sound when the eyes cannot help.
The midnight peak that many city residents notice, roughly between midnight and 2 a.m., coincides with the quietest period of urban noise. The gulls may not actually call more at that hour. They may simply be more audible because the city has finally gone quiet enough for human ears to hear what has been going on all along.
The Rain Dance
On fields and lawns across Europe, gulls perform a behavior that looks like rapid tap-dancing. A bird stands on grass and stamps its feet in quick alternation, sometimes for thirty seconds or more. The motion is rhythmic, deliberate, and oddly hypnotic.
The technique is a hunting strategy. The rapid foot-tapping produces vibrations in the soil that mimic the pattern of rainfall. Earthworms, which travel faster on wet surfaces than through soil, interpret the vibrations as rain and move toward the surface. The gull eats them.
The trick works because of how earthworms sense their environment. Moving through soil is energy-expensive. Surface travel is faster and covers more distance, but worms can only do it safely when the ground is wet. When they feel vibrations consistent with rain, they head up. The gull’s feet deliver a convincing forgery.
Humans figured out the same principle independently. Worm-grunting, worm-charming, and worm-fiddling are documented folk practices across Europe and North America. In the American South, practitioners drive a wooden stake into the ground and rub a strip of metal across it, producing vibrations that bring worms to the surface for use as fishing bait. A 2008 study by Vanderbilt University researcher Ken Catania found that the vibration frequencies used by Florida’s worm grunters closely match the frequencies produced by digging moles, the earthworm’s main underground predator. The worms come up not because they think it is raining but because they think a mole is coming.
Whether gulls stumbled onto this behavior through trial and error or learned it by watching other gulls is unclear. The behavior appears more common in inland populations, where gulls have moved away from marine food sources and adapted to terrestrial foraging. Coastal gulls rarely need to stomp for worms when the tide delivers food twice a day.
The Gull That Hunts by Moonlight
Every gull on Earth hunts during the day. Except one.
The swallow-tailed gull (Creagrus furcatus) of the Galapagos Islands is the only fully nocturnal gull and the only fully nocturnal seabird. It breeds on the rocky shores of several Galapagos islands and flies out to sea at dusk to hunt squid and small fish that rise from the deep to feed on plankton at the surface.
The swallow-tailed gull’s eyes are the largest of any gull species by both diameter and volume. Like cats, their eyes contain a tapetum lucidum, a reflective layer behind the retina that bounces light back through the photoreceptors, effectively doubling the light available for vision.
The bird hunts up to 30 kilometers offshore, far beyond sight of land, and prefers to hunt during new moons when the ocean surface is darkest. Its prey, bioluminescent squid and fish, glow faintly in the black water. The gull’s oversized eyes, adapted for minimal light, spot these faint signals from the air.
The strangest part of the swallow-tailed gull’s hunting behavior is its sound. While chasing prey, the bird emits a rapid series of clicking calls that researchers have described as “amazingly reminiscent of the bursts of echolocation clicks made by hunting dolphins.” The clicks are distinct from any other gull vocalization and occur only during active pursuit of prey.
The obvious question: is this echolocation? True echolocation, using sound to map the environment by interpreting returning echoes, is confirmed in only two groups of birds: oilbirds in South American caves and certain swiftlet species in Southeast Asian caves. Both use echolocation to navigate in total darkness, not to catch prey. No bird is confirmed to use echolocation for hunting. Whether the swallow-tailed gull’s clicks serve a navigational, communicative, or echolocative function remains an open question. The clicks exist. Their purpose is not yet understood. For more on how ancient peoples understood the relationship between sound and physical space, see Acoustic Archaeology: When Stone Was Tuned to Sing.
The Thief’s Brain
Gulls steal food. Everyone who has eaten chips near a beach knows this. What fewer people know is how calculated the theft is.
The scientific term is kleptoparasitism: obtaining food by taking it from another animal that caught or found it. Many bird species do this occasionally. Gulls have turned it into a primary foraging strategy, and research shows they are remarkably strategic about it.
Studies on herring gulls stealing from Atlantic puffins found that gulls preferentially attacked puffins carrying larger fish loads. They also chose targets that landed closer to them, minimizing pursuit distance. The decision to steal or not appeared to involve a cost-benefit calculation: is the likely payoff worth the energy of the chase and the risk of confrontation?
A 2023 study published in Biology Letters by the Royal Society took this further. Researchers at the University of Sussex found that herring gulls engaged in “inter-species stimulus enhancement,” a technical way of saying they watched what humans picked up and then went after the same food. When a human handler chose one of two food items, nearby gulls were significantly more likely to approach that item afterward. The gulls were reading human behavior and using it to make foraging decisions.
This cognitive flexibility may be connected to brain architecture. Research across bird families shows that kleptoparasitic species tend to have larger brains relative to body size than their hosts. The neural overhead required to observe another animal’s behavior, judge the timing, calculate the approach, and execute the theft appears to demand more processing power than simply finding food yourself.
Gulls can drink both fresh and salt water. They have specialized glands above their eyes that filter sodium from the blood and excrete a concentrated saline solution through the nostrils. Most birds would dehydrate from drinking seawater.
Rome’s gulls demonstrate this flexibility daily. They have learned the schedules of outdoor markets. They know which restaurant tables are occupied and which are not. They time their approaches to the moment a diner looks away. This is not instinct. This is observation, memory, and planning, the same cognitive toolkit that makes crows such effective problem-solvers.
Sailors’ Souls
Along the coast of Great Britain, an old belief holds that seagulls carry the souls of drowned sailors. The earliest documented reference dates to 1878, but the tradition is almost certainly older. Killing a gull was considered profoundly unlucky, especially at the start of a voyage. A sailor who harmed a gull risked angering the spirits of the sea.
The logic ran like this: when a sailor drowned far from shore, his soul could not rest as the souls of those who died on land could. Instead, it entered a gull, a bird that lived between sea and sky, between the human world and the vast unknown of open water. The gull became a vehicle for the soul’s restless continuation, forever tied to the ocean where the body was lost.
In Irish mythology, the sea god Manannan Mac Lir sometimes took the form of a gull. He was a shapeshifter and a trickster, but also a figure of intelligence, creativity, and protection. Fishermen who saw gulls following their boats interpreted the birds as signs of Manannan’s favor, or at least his attention.
The belief is not limited to Europe. In Japanese Shinto tradition, gulls sometimes appear as messengers of sea deities. Among the Haida people of the Pacific Northwest, gulls are regarded as wise spiritual advisors. Coastal Native American tribes across North America viewed gulls as messengers moving between the physical world and the spiritual one. The specific roles vary, but the pattern repeats: cultures that lived alongside gulls, watched them, and depended on the same oceans treated these birds as more than animals.
One widespread superstition holds that three gulls flying directly overhead is a sign of impending death. Whether this belief reflects the simple observation that gulls gather where dead or dying things are found, or whether it carries a deeper symbolic weight, depends on who you ask.
The Crazy Alchemist position on this is straightforward. The belief that gulls carry the souls of the dead appears independently across cultures separated by oceans and centuries. The British, Japanese, Irish, and Pacific Northwest traditions had no mechanism for transmitting this idea to each other. The pattern exists. What it means is a question each reader will answer differently.
What We Still Don’t Know
Nathan Pieplow, who has studied gull vocalizations more closely than most, described them as “underexplored.” For a bird family that lives alongside humans on every continent except Antarctica, we know surprisingly little about the full structure of their communication.
Individual voice recognition is confirmed. Gulls know their mate’s call from a stranger’s call, and they distinguish the calls of established neighbors from unfamiliar intruders. But the acoustic mechanism behind this recognition, exactly which features of the call carry the identity signal, is still being mapped.
The question of learned versus innate behavior remains partially open. Chick begging calls appear innate, present before hatching. But the long call’s individual distinctiveness suggests a component of vocal learning, a refinement of the call over the bird’s lifetime that makes it uniquely identifiable. How much of each call type is hardwired and how much is shaped by experience and social environment is not fully resolved.
Rome at two in the morning. A gull on a television antenna throws its head back and delivers a long call. Three rooftops away, another gull answers. Between them, a chuckling alarm note from a third bird who has spotted something moving on a balcony. The calls overlap, cascade, fade, then start again.
We know the names of these calls now. We know some of what they mean. We know the postures that accompany them and the contexts that trigger them. Tinbergen gave us the framework. Decades of fieldwork have filled in details. But the full conversation, the thing that happens when dozens of gulls vocalize simultaneously across a sleeping city for hours, is something we are still learning to hear.
