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Discover the Fascinating Behavior of Audouin’s Gull: From Foraging to Breeding and More!

Audouin’s Gull: A Jewel of the Mediterranean

If you are wandering around the Mediterranean coast, you may come across an Audouin’s Gull (Ichthyaetus audouinii). This bird is popular among birdwatchers due to its unique features and colorful appearance.

In this article, we will explore different aspects of this fascinating species, from its identification to its plumages.


The Audouin’s Gull is a medium-sized gull that stands out from other gulls due to its striking features. The adult bird has a white body, while its wings are a light grey color with black tips.

The bird’s most distinguishing feature is its bill, which is bright yellow, with a red spot on the lower mandible, that glows like a ruby in the sun. Field


The Audouin’s Gull is commonly seen during the breeding season in its nesting colonies on rocky shores and cliffs.

You can spot this gull by its characteristic call, a loud, nasal “koa” or “kau.” In flight, its wings appear broad and blunt, and it shows a distinct dark band along the trailing edge of its wings.

Similar Species

The Audouin’s Gull has some similarities with other gull species. It may be challenging to distinguish it from the Yellow-legged Gull (Larus michahellis) and the Herring Gull (Larus argentatus).

However, compared to the Yellow-legged Gull, the Audouin’s Gull has a shorter bill, while the Herring Gull has darker wings with white spots on their tips, and their bills are pinkish.


The Audouin’s Gull goes through various plumages in its lifetime, which are essential in its identification.

Juvenile Plumage

The juvenile plumage comes after hatching and lasts for about two years. It is brown and lighter underneath, with an indistinct pattern on its feathers.

First Winter Plumage

The first winter plumage is a transition between the juvenile and adult plumage, and it lasts from the third to the fifth year of the bird’s life. The bird has substantial white feathers on its head, neck, and body, with dark edges, and its wings become grey.

Adult Plumage

The adult plumage is reached by the fifth year of the bird’s life. The body and wings are white and pale grey, respectively, as we previously described.

It is at this stage when the bird develops its yellow bill with a red spot on its lower mandible.


Molting is the process when birds replace their feathers. The Audouin’s Gull goes through two molts in its lifetime, which are critical in its development.

Partial Molt

The partial molt occurs in the summer between June and September and affects the bird’s head and neck feathers, transforming into the adult plumage.

Complete Molt

The complete molt happens between November and January and affects the bird’s wings and body. The bird drops all its feathers, and new ones grow back, lasting until the next molt.

In conclusion, the Audouin’s Gull is a remarkable bird species with striking features that make it easy to identify. Its jewel-like bill and bright colors make it one of the most popular gulls in the Mediterranean.

Learning about its plumages and molts can be a thrilling experience for any birder. Remember, the next time you visit the coast, keep an eye for this jewel of the Mediterranean!

Audouin’s Gull: A Journey Through Systematics and Distribution

The Audouin’s Gull (Ichthyaetus audouinii) has been a subject of study among ornithologists for many years.

Its systematics history is fascinating, and its distribution has undergone several changes over time. In this article, we will delve deeper into its geographic variation, subspecies, related species, and historical changes to its distribution.

Systematics History

The Audouin’s Gull was initially classified as a subspecies of the Common Gull (Larus canus) due to its resemblance to the Herring Gull (Larus argentatus). However, in 1971, it was reclassified as a separate species due to its unique characteristics.

This reclassification was done based on its DNA sequences, vocalizations, and differences in size, morphology, and behavior.

Geographic Variation

There are slight variations in the physical appearance of the Audouin’s Gull, depending on its location. These variations are often referred to as geographic variation.

In the western Mediterranean, the gulls have a larger body size and longer wings, while the eastern Mediterranean populations have a smaller body size and shorter wings. Despite the differences in size, all individuals have the same distinctive colors and bill shape.


The Audouin’s Gull has two recognized subspecies:

Ichthyaetus audouinii audouinii – This subspecies is found in the western and central Mediterranean, including the Balearic Islands, Algeria, and Tunisia. Ichthyaetus audouinii payesii – This subspecies is found in the eastern Mediterranean, including the Aegean and Adriatic Seas, and the eastern coast of the Black Sea.

These subspecies differ mainly in their size, and they also have different breeding seasons. While I.

a. audouinii breeds from April to July, I.

a. payesii breeds from May to September.

Related Species

The Audouin’s Gull belongs to the Laridae family, which consists of gulls and terns. It is closely related to other Mediterranean gulls, including the Yellow-legged Gull (Larus michahellis), the Slender-billed Gull (Chroicocephalus genei), and the Black-headed Gull (Larus ridibundus).

The Yellow-legged Gull is its most closely related species, and it is often mistaken for the Audouin’s Gull.

Historical Changes to Distribution

The Audouin’s Gull had a limited range during the early 20th century. It bred only in a few colonies located in Spain and Algeria, and its population was estimated to be about 1,000 pairs.

However, because of conservation efforts and changes in fishing practices, the species has made a remarkable recovery and expanded its range significantly. The first successful conservation measure for the Audouin’s Gull was the establishment of a protected sea-grass meadow in Spain in the 1960s.

This meadow helped to increase the number of fish available to the gulls, leading to population growth. Later, in the 1980s, a similar program was established in Algeria, leading to an expansion of the species’ breeding distribution.

Today the Audouin’s Gull has a larger range that covers the western and central Mediterranean, including the Balearic Islands, Morocco, Algeria, Tunisia, and Sardinia. The population of the Audouin’s Gull has also increased significantly, with an estimated 15,000 pairs in the early 2000s.

The distribution of the Audouin’s Gull has continued to change as gulls have started to breed in new areas. For example, a colony was discovered in the Rosignano Solvay industrial plant in Tuscany, Italy, in 2002.

Since then, the species has continued to expand its range, breeding in new areas such as Corsica, Calabria, and Puglia, in Italy. In conclusion, the Audouin’s Gull has undergone significant changes in its distribution over the years.

The expansion of their range has been due to conservation efforts and changes to fishing practices, leading to an increase in their population. Despite these changes, the species has maintained its unique characteristics, making it an intriguing bird species for ornithologists to continue to study.

Audouin’s Gull: A Look at Its

Habitat and


The Audouin’s Gull (Ichthyaetus audouinii) is an interesting bird species that inhabits the Mediterranean region. This bird’s habitat and movements have intrigued ornithologists for many years.

In this article, we will take a detailed look at the Audouin’s Gull’s habitat, movements, and migration.


The Audouin’s Gull’s preferred habitat is rocky shores, cliffs, and small-island breeding sites. They primarily build their nests on rocky cliffs and edges, which protect their eggs from predators.

They also like to roost on rocky ledges offshore, especially during the non-breeding season. The gull has adapted to an urban landscape and is known to forage in urban areas, such as ports and waste dumps.

Breeding colonies are often located in secluded areas to avoid disturbance. These colonies are typically situated near the shore, with small rocky islands being the most popular breeding sites.

The Audouin’s Gull relies on sand, mud, and gravel to build their nests, which they create in hollows on the rocky surface. During the nesting period, they display aggressive behavior to defend their territory and chicks.


The Audouin’s Gull is a resident bird species, remaining in the Mediterranean throughout the year. However, there are minor movements between breeding and non-breeding areas in search of better food sources and roosting sites.

The movements are usually not extensive, with birds covering short distances, such as between the nearest island and the mainland. During the winter season, Audouin’s Gulls can be seen gathering in flocks offshore or around ports or other food sources, such as shopping centers.

These flocks are mixed, with different ages, ranging from immature birds to adults.


Audouin’s Gulls are not migratory, but they can exhibit slight movements during certain times of the year. The northernmost breeding colonies in the Balearic Islands move south due to the cooler weather in late autumn and winter.

These movements are minor, with birds travelling up to several hundred kilometers to escape harsh weather conditions. Young individuals may also undergo some form of migration, although the exact routes and destinations are not yet fully understood.

These juveniles may travel hundreds of kilometers from their breeding colonies in search of food and better roosting sites. The movements of Audouin’s Gulls are influenced by several factors, including weather conditions, food availability, predation risk, and habitat fragmentation.

Coastal development resulting in the destruction of breeding sites can force the birds to relocate and search for suitable habitats. In conclusion, the Audouin’s Gull is a resident species of the Mediterranean region, with slight movements during the year.

Their habitat preference ranges from rocky coasts, cliffs, to small islands for breeding. The gulls can also adjust to an urban landscape, foraging in ports and waste dumps.

The movements of Audouin’s Gulls are minor, usually short and driven by weather and food conditions. Younger individuals may also undertake minor movements, driven by the search for food and brooding sites.

As coastal development continues, it is essential to monitor the effect on these birds’ movements and habitats. Audouin’s Gull: A Look at Its

Diet, Foraging, and Vocal


The Audouin’s Gull (Ichthyaetus audouinii) is a fascinating bird species with unique characteristics that have captivated the interest of ornithologists for many years.

In this article, we will delve into the Audouin’s Gull’s diet, foraging behaviors, and vocalizations.

Diet and Foraging

The Audouin’s Gull is primarily a coastal seabird that feeds on fish, crustaceans, cephalopods, and other marine invertebrates. They have a diverse diet and will eat a wide range of prey items, depending on what is available.

They use their sharp, curved beaks to catch and consume their prey, which they achieve by diving into the water and snatching the prey underwater. They are capable of plunging underwater up to depths of 15 meters and remaining underwater for about 30 seconds.


The Audouin’s Gull feeds on small fish species such as anchovies, sardines, herrings, and small crustaceans such as shrimps, crabs, and squid. They prefer to feed within 10 km of the coast line, but they can also venture further offshore when searching for food.

In some cases, they also feed on garbage in landfills, especially during the breeding season when food is scarce.


The Audouin’s Gull diet has a significant impact on the food chain of the Mediterranean coastal region. The species feeds on fish species that are essential to the ecosystem, making them an indicator of the region’s health.

Changes in their behavior, such as a shift to feeding on non-native prey or ingesting microplastics, can be a red flag for the health of the environment.

Metabolism and Temperature Regulation

The Audouin’s Gull has adapted to the hot, dry climate of the Mediterranean region by having an efficient metabolism and temperature regulation system. They have a high metabolic rate, which allows them to maintain their physiological functions even in extreme heat.

They have an efficient thermoregulatory system that allows heat exchange with the surrounding environment, keeping them cool in hot weather.

Sounds and Vocal


Vocalizations are essential in the social lives of birds, and the Audouin’s Gull is no exception. The birds use an intricate system of calls, songs, and postures to communicate with each other.

The most common call of the Audouin’s Gull is a nasal “koo-ah” or “koo-oo,” which is often repeated several times in a row.


The Audouin’s Gull is a highly vocal bird, especially during the breeding season. They use vocal cues to communicate with their partners, chicks, and other members of the colony.

The basic call of the species is a nasal “koo-ah” or “koo-oo,” which is used for a variety of purposes such as warning of predators, attracting a mate, and communication within the colony. During the breeding season, the males use a different call to court females.

The call is similar to the basic call but louder and more frequent. The courtship display involves the flapping of wings, bowing, and shaking motions.

The females respond to these displays, leading to pair bonding. In conclusion, the Audouin’s Gull is a fascinating bird species with unique characteristics that make it an attractive subject for ornithologists.

The bird has a diverse diet that primarily includes fish, crustaceans, cephalopods, and other marine invertebrates. The thermoregulatory and metabolic adaptations of the bird make it uniquely suited to the hot and dry Mediterranean climate.

The birds use an intricate system of vocalizations and postures to communicate with each other, with the basic call being a nasal “koo-ah” or “koo-oo.” The species’ courtship display involves behaviors such as wing flapping and bowing, leading to pair bonding. Audouin’s Gull: A Close Look at Its


Breeding, and Demography

The Audouin’s Gull (Ichthyaetus audouinii) is an intriguing bird species that has unique behavioral characteristics.

These behaviors range from foraging to breeding and have fascinated ornithologists for many years. In this article, we will take a closer look at the Audouin’s Gull’s behavior, breeding habits, and its demography and populations.


The Audouin’s Gull has unique behaviors that enable it to survive in a harsh, coastal environment. These behaviors include locomotion, self-maintenance, agonistic behavior, and sexual behavior.


The Audouin’s Gull is a strong flier capable of soaring long distances and diving underwater to catch prey. They have broad wings and a streamlined body that allows them to fly efficiently in strong coastal winds.

In addition, they have strong legs and feet for walking and swimming on the rocky shores where they breed.


The Audouin’s Gull spends a significant portion of its day preening itself to maintain its feathers’ condition. Preening helps to remove dirt and parasites from the feathers, keeping them healthy and functional.



Agonistic behavior is a form of behavior exhibited by animals during competition and conflict. The Audouin’s Gull exhibits agonistic behavior during the breeding season when they compete for territories and resources, such as food and nesting sites.

Agonistic behavior includes courtship and territorial displays, such as wing flapping, bill pecking, and vocalizations. Sexual


Sexual behavior is an essential aspect of a bird’s life, and the Audouin’s Gull exhibits unique sexual behaviors during the breeding season.

The males perform courtship displays to attract females, such as bowing, head nodding, and wing flapping. Once the female accepts the male’s display, the pair will perform mutual preening and mate.


The Audouin’s Gull breeds in colonies on rocky islands, sea cliffs, and coastal islets. The breeding season begins in late March and ends in July.

The birds arrive at the nesting sites ready to mate, after which the females lay one or two eggs in a hollow on the rocky surface. The pair incubates the eggs for approximately 26 to 29 days, after which the chicks hatch.

The chicks are born with semi-downy feathers and are unable to thermo-regulate, so they rely on their parents for warmth.

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