Sun compass in animals internal clock to determine their heading, and that they had learnt the actual direction down to the sea on their particular beach. Lockley's experiments with Manx shearwaters ("Puffinus puffinus") showed that when released "under a clear sky" far from their nests (in Skokholm), the seabirds first oriented themselves and then "flew off in a direct line for Skokholm", making the journey rapidly. For example, one of the birds, released at Boston airport, arrived in Skokholm 12½ days later; Lockley calculated that if the birds flew for 12 hours per day, they must have travelled at 20 miles per hour, their
Christmas shearwater and introduced black rats took eggs and chicks. In 1985, the population on Sala-y-Gómez, a nature sanctuary, was estimated at 5,000. With its wide range and considerable numbers, the Christmas shearwater is considered a species of least concern by the IUCN. Christmas shearwater The Christmas shearwater ("Puffinus nativitatis") is a medium-sized shearwater of the tropical Central Pacific. It is a poorly known species due to its remote nesting habits, and it has not been extensively studied at sea either. It is one member of a very ancient lineage of the small "Puffinus" species. Its only close living relative is the