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
Dune shearwater which bred in lava fields. Extinction of the species occurred about 2000–3000 years ago, contemporaneously with the first human settlement of the islands by the Guanches, with the cause likely to be human predation. Dune shearwater The dune shearwater ("Puffinus holeae"), also known as the Canarian shearwater or Hole's shearwater, was a relatively large shearwater which bred in the Canary Islands archipelago of the North Atlantic Ocean. Fossils have also been found in the Figueira Brava cave archaeological site on the western coast of Portugal. The specific epithet honours Mrs Jean Hole who collected fossil material of the species on