They forage from heights of up to with no clear preference, and typically dive from between . They dive with their bodies straight and rigid, wings tucked close to the body but angled back, extending beyond the tail, before piercing the water like an arrow. They control the direction of the dive using their wings and tail, and fold their wings against the body just before impact. Birds can hit the water at speeds of up to . This allows them to penetrate up to below the surface, and they will swim down to an average , sometimes deeper than . The bird's subcutaneous air sacs may have a role in controlling their buoyancy.