Tern colonies including common, Arctic, and little terns face welfare challenges from human disturbance, predation, and climate-driven prey shifts.
Tern chicks disturbed from nesting areas face hypothermia and predation. Adults performing distraction displays to lure humans from chicks expend significant energy and create opportunities for predators to access nests. Repeated disturbance causes breeding failure that represents welfare harms at both individual and population levels. Wardened tern colonies with exclusion fencing prevent these welfare harms at relatively low cost with major conservation benefit.