Terns are a group of generally medium to large seabirds typically with grey or white plumage, often with black markings on the head. Most terns hunt fish by diving but some pick insects off the surface of fresh water. Terns are generally long-lived birds, with several species known to live in excess of 30 years.
In the context of seabirds, terns are typically medium to large-sized birds with grey or white feathers and distinctive black markings on their head. They primarily feed on fish by diving into the water, although some capture insects from the surface of freshwater bodies. Terns are also notable for their remarkable longevity, with several species living up to 30 years or more.