The storm petrel normally flies within of the water surface and typically feeds by picking items off the sea as it patters over the surface. Birds have been observed diving for food to a depth of not more than . and it is claimed, using indirect measurements, that the Mediterranean subspecies reaches depths of up to ). A bird may range up to over the course of two or three days in search of food. Although the bird usually feeds during the day, in the breeding season petrels will often feed at night close to the shore.