Gulls are sea birds of the Laridae family. The most well-known species are herring gulls, which include sea gulls, black-headed gulls, great black-backed gulls of Europe and North America and lesser black-backed gulls. Gulls have long bodies, large heads, strong, hooked beaks and long, tapered wings. Their wingspan is a meter wide. The feathers of adult gulls are usually white, gray or black. Young gulls are speckled brown. Gulls usually make their nests in large colonies, often near to humans. They leave these colonies only during mating season. Gulls live both along the coast and inland, some live in arctic regions. Gulls are spectacular fliers. They soar in air currents to save energy. Gulls are omnivorous. They eat fish and mollusks for the most part, although over the years gulls have also learned scavenge food from human trash and vegetation.

Gulls mate in spring and summer. Couples form and stay together through the season. Gulls are generally monogamous. During mating rituals, males behave aggressively. Females interpret this display as a sign of strength. After mating, gulls build nests. Females lay two or three eggs at most. The male and female take turns incubating the eggs for 20 to 30 days. Newly-hatched, chicks are covered in dark mottled down. Their eyes are open and they can already stand. Young gulls are fed by their parents, who regurgitate food into their beaks. Herring gull chicks instinctively associate the red mark on their mothers' beaks with food. They peck her there to signal that they are hungry. When gulls are four to six weeks old, they start to grow feathers. They leave the nest and begin flying when they are seven weeks old. Flying gulls symbolize freedom, independence and elation. In Indian mythology, the gull is a “bringer of light.” A similar take on this bird was offered by Richard Bach in his novella Jonathan Livingston Seagull. The sea gull in the book embodies the joy of living. His story is the search for personal fulfillment and for an intimate and profound link with nature.