Gulls are an easily recognizable and familiar group of birds, but what makes a gull a gull? What characteristics does this highly variable group of birds share, and how can birders easily recognize a bird as a type of gull?
Types of Gulls
There are more than 50 species of gulls in the world, though the exact count of distinct species can vary based on how subspecies are classified. All gulls are part of the bird family Laridae, and they are related to terns and auks, and more distantly related to other seabirds and shorebirds.
Gull Geography
Gulls are found throughout the world in both coastal and inland habitats. While the misnomer "seagulls" gives the impression that these birds are only found near saltwater, in fact gulls are found near most large bodies of both fresh and salt water. Many types of gulls are also found far from the coast and thrive in both agricultural and urban habitats, including areas such as parking lots, landfills, parks and golf courses.
Gull Physiology
Gulls have a distinct look, thanks to a combination of unique physiological characteristics.
- Size: With body lengths ranging from 12-30 inches depending on the species, gulls are often the largest birds along the shores and in habitats they prefer.
- Body Shape: Most gulls have deep, broad chests and abdomens, with very short tails. Their slender necks can be held in compact or elongated poses, and their heads are rounded.
- Feet: Gulls have strong webbed feet with small talons. These broad feet allow gulls to take off quickly from the water but they also walk well on land.
- Wings: Gulls' wings are long, narrow and tapered, giving them a powerful and easy flight even in windy areas. Gulls can soar for long periods without flapping.
- Bill: There is quite a bit of variety in gulls' bills, but many are stout and strong to help these birds take advantage of a widely varied diet. The bills often have markings such as colored spots on the mandible, colored tips or contrasting bands.
- Plumage: Gulls are not typically colorful, and their plumage is most frequently white, gray and back, with brown mottling in winter and for juvenile birds. The legs and bill are often far more colorful and can be the best field marks.
By knowing what gives gulls a distinctive appearance, birders can be better prepared to accurately identify these confusing birds.
Gull Behavior
Gulls are not only distinct in appearance, but their behavior can be easily recognized as well.
- Feeding: Gulls are opportunistic, omnivorous scavengers that will eagerly try any food source. They will pick through trash, feed on carrion or forage for more natural food sources, and when feeding in flocks they will often fight over choice morsels.
- Vocalizations: These are noisy birds in all circumstances, particularly in flocks. Though their calls are not very distinct across different species, the classic "gull" call is clearly recognizable for this family of birds.
- Crossbreeding: Gulls easily hybridize with one another, and crossbreeding is more common among gulls than with other types of wild birds. Because of this, however, hybrid gulls add another degree of difficulty for gull identification.
- Maturity: Gulls take between two and four years to reach maturity, and subadult birds have wide variation in their plumage patterns and colors. This is challenging for identification but helps distinguish gulls from other birds along the shore.
Gulls can be simultaneously fascinating and frustrating to many birders, but understanding what makes these birds unique can help birders be more fascinated than frustrated whenever they see a gull.
Photo – Western Gull © Kathy & Sam
