... 2 ) in emperor penguins ( Aptenodytes forsteri ) equipped with backpack P O 2 recorders. Cervical air sac P O 2 values at rest were lower than in other birds, while the cervical air sac to posterior thoracic air sac P O 2 difference was larger. Pre-dive cervical air sac P O 2 values were often...

... Washington at night; if breeding males do this too, feeding before egg laying will help them endure the subsequent 65 day incubation of the egg. Aptenodytes forsteri Winter Cape Washington After the discovery of an emperor penguin ( Aptenodytes forsteri , Gray 1844) colony at Cape Crozier...

... Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan † Author for correspondence ( koshio@aori.u-tokyo.ac.jp ) 4 10 2011 © 2012. 2012 dive path acceleration Aptenodytes forsteri Breath-holding divers are always in a dilemma during...

... of this behaviour in emperor penguins ( Aptenodytes forsteri ), whose failed breeders often kidnap chicks. We experimentally tested the hypothesis that kidnapping behaviour was the result of high residual levels of prolactin (PRL), a hormone involved in parental behaviour. Penguins with artificially decreased PRL...

...T. Knower Stockard; J. Heil; J. U. Meir; K. Sato; K. V. Ponganis; P. J. Ponganis SUMMARY In order to determine the rate and magnitude of respiratory O 2 depletion during dives of emperor penguins ( Aptenodytes forsteri ),air sac O 2 partial pressure ( P O 2 )was recorded in 73 dives of four birds...

... dive duration. * Author for correspondence (e-mail: pponganis@ucsd.edu ) 16 9 2002 © The Company of Biologists Limited 2002 2002 accelerometer aerobic dive limit Aptenodytes forsteri Crittercam dive emperor penguin stroke frequency Burst swimming (stroke...

...P. J. Ponganis; R. P. Van Dam; G. Marshall; T. Knower; D. H. Levenson ABSTRACT Emperor penguins ( Aptenodytes forsteri ) were equipped with a remote underwater video camera, the Crittercam, to evaluate sub-ice foraging behavior while the birds dived from an isolated dive hole. Three birds dived...

...P. J. Ponganis; L. N. Starke; M. Horning; G. L. Kooyman ABSTRACT To compare the diving capacities of juvenile and adult emperor penguins Aptenodytes forsteri , and to determine the physiological variables underlying the diving ability of juveniles, we monitored diving activity in juvenile penguins...

...P. J. Ponganis; G. L. Kooyman; L. N. Starke; C. A. Kooyman; T. G. Kooyman ABSTRACT In order to determine an aerobic diving limit (ADL) in emperor penguins ( Aptenodytes forsteri ), post-dive blood lactate concentrations were measured in penguins foraging at an isolated sea ice hole. Resting lactate...

...G. L. Kooyman; P. J. Ponganis ABSTRACT Oxygen consumption , heart rate and blood chemistry were measured in four emperor penguins, Aptenodytes forsteri (Gray), during graded swimming exercise. The maximum obtained, 52 ml O 2 kg −1 min −1 , was 7.8 times the measured resting of 6.7 ml O 2 kg −1 min...

... Aptenodytes forsteri If the term ‘diving’ is restricted to those swim activities in which an animal is voluntarily submerging itself under natural or quasi-natural conditions, then there have been few physiological studies of diving in aquatic animals. Most ‘diving’ experiments have been carried out...