The bird commonly seen soaring over coastlines and aggressively snatching food is one of the world’s most recognizable, intelligent, and adaptable avian species. Although often associated solely with the ocean, this creature is globally distributed, successfully colonizing almost every type of environment, from city centers to remote inland fields. Their striking appearance and distinct, loud calls make them a ubiquitous presence in human-dominated landscapes worldwide, due to their ability to exploit diverse food sources.
Gulls: The Correct Terminology
The term “seagull” is a common colloquialism, but the scientifically accepted name for this group of birds is simply “gull.” Gulls belong to the family Laridae, which includes around 100 species.
While the family Laridae also includes the smaller, more graceful terns, gulls are distinct in their heavier build and broader wings. The continued use of “seagull” stems from the fact that many visible species are found in coastal areas. However, this generalized name ignores the variety among the approximately 45 different species of gulls, many of which rarely see the ocean.
Identifying Key Physical Traits
Gulls are medium-to-large birds, with size varying considerably between species, from the little gull to the great black-backed gull, which can reach 81 centimeters in length. Most adults share a color pattern of a white head and body contrasted by a mantle of gray or black on the back and wings.
Their feet are fully webbed, aiding in swimming, but they are also adept at walking on land compared to many other seabirds. Gulls possess a stout, longish bill that is slightly hooked at the tip, which is used for grasping and tearing food. Identification can be challenging because many species take a long time to mature, with some large gulls needing up to four years to achieve full adult plumage.
Diverse Habitats and Distribution
Although often called “seabirds,” gulls are not restricted to marine environments. Their distribution is nearly global, and they thrive in diverse habitats, including freshwater lakes, large rivers, and wetlands. This adaptability has allowed many species to colonize inland areas far from the coast.
Gulls are common in human-dominated landscapes. They frequent agricultural fields, following plows to feed on upturned grubs, and urban environments, where they exploit human waste near parking lots and landfills. Depending on the species and latitude, gulls can be year-round residents or long-distance migrants, often moving inland or south to seek milder winter conditions.
Opportunistic Feeding Behaviors
Gulls are opportunistic carnivores and scavengers, maintaining a varied diet. Their food sources include small fish, insects, crustaceans, eggs, and small rodents. They are well-known for scavenging, readily consuming carrion and human refuse from dumps, making them effective clean-up crews.
The birds exhibit sophisticated feeding methods. For instance, some gulls drop hard-shelled mollusks and sea urchins onto rocks or paved surfaces from a height to break them open. Gulls are also social feeders, often gathering in large, noisy groups to exploit a concentrated food source or to cooperatively rob food from other birds.