FURTHER EXPERIMENTS ON DISTANCE NAVIGATION IN THE ADELIE PENGUIN PYGOSCELZS ADELZAE

• Published in: Ibis
• Main Authors: Penney, R. L., Emlen, J. T.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1967
• Subjects: Cape Crozier; Crozier; South Pole; Adelie penguin; Antarc*; Antarctica; Pygoscelis adeliae; South pole
• Online Access: http://dx.doi.org/10.1111/j.1474-919x.1967.tb00006.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1474-919X.1967.tb00006.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1474-919X.1967.tb00006.x

Summary Further experiments confirm our recently reported findings that Adelie Penguins Pygoscelis adeliae , transported from rookeries on the coasts of Antarctica to remote release points, consistently select a departure direction to the N.N.E. with respect to their home meridian. New releases were made at the South Pole where sun altitude is constant and in the offshore pack ice where the initial N.N.E. departure direction led the birds directly away from their home. Birds imported from the Mirnyy coast, 85° of longitude to the west of Cape Crozier selected a departure direction to the N.W. After being held in an open pen at the new position for three weeks, however, Mirnyy birds revised their orientation to match the N.N.E. departures of a comparably held group of Crozier birds. Juvenile penguins taken from creches and from the beach at Cape Crozier selected the same departure direction as adults. Several lines of evidence suggest that the mechanism used in initial direction selection may be different from that used in course maintenance. The consistent northward or outward departure orientation is discussed in terms of escape to offshore feeding grounds. The easterly component of this orientation is discussed in terms of compensation for a westward drift imposed on outward‐moving birds by coastal currents. A circadian rhythm in phase with conditions at the longitude of the home rookery is regarded as serving to guide a displaced bird back to its home coast. A circadian rhythm reset to the solar cycle of a new longitude is regarded as serving to guide a displaced bird to the nearest coast. The return of displaced birds to their home rookery, after initial orientation in other directions, emphasizes the fact that the departure response observed in these studies is only one part of a complex navigational mechanism, which guides the Adelie Penguin through its seasonal migrations.