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
Saba (IBA AN006 "Saba Coastline") by BirdLife International. Saba is home to about sixty species of birds, many of which are sea birds that use the holes and crevices of the steep cliffs and two small islands for breeding and feed in the waters around the island. Saba’s shoreline is home to the Caribbean’s largest breeding colony of Red-billed tropicbird ("Phaethon aethereus"). The Audubon's Shearwater ("Puffinus lherminieri") is another common bird, and is the national bird of Saba as well as being featured on their coat of arms. Being an island, Saba is home to a number of endemic species including