IV.

Behavior

Territory defense, pair formation, parent-chick interactions, and other gull activities involve communication behavior consisting of postures, movements, and calls, some of which are quite complex both in form and in function. For example, courting gulls perform threat displays, but they do so in sequences that apparently modify the meaning of the display. Recognition of one individual by another by such means has been demonstrated experimentally. Pair bonds may be long lasting.

Gulls may thrive at the expense of other species. For example, larger gulls are known to drive out smaller gulls and terns from nesting territories, partly through egg and chick predation. The scavenging of gulls can also affect the ecology of urban environments. Airfields (and the garbage dumps that are commonly located near them) attract large numbers of gulls, which present a collision hazard to aircraft; this problem has yet to be solved. In some places, gulls' eggs are collected for food.

Scientific classification: Gulls belong to the family Laridae in the order Charadriiformes.