Metabolism, body temperature and thermal conductance of fruit-doves (Aves: Columbidae, Treroninae).
Basal metabolic rate (MR), body temperature (T(b)) and wet thermal conductance (C(wet)) of three tropical species of fruit-doves were investigated at ambient temperatures (T(a)) of 11-33 degrees C in activity (alpha) and rest (rho) phases to investigate the possible effect of obligate frugivory on the physiology of columbids. The basal metabolic rates of Ptilinopus melanospila (black-naped fruit-dove, 94 g), Drepanoptila holosericea (cloven-feathered dove, 198 g) and Ducula pinon (Pinon's imperial pigeon, 748 g) are 20-38% lower than predicted for all birds, including granivorous columbid species from temperate and tropical regions. The MR was minimal at a T(a) value of approximately 30 degrees C (=lower critical temperature, T(lc)) for all three species, indicating that these rainforest birds are not able to withstand high ambient temperatures as well as arid-adapted members of the pigeon family. Minimal wet-thermal conductance was, on average, higher than expected, indicating poor insulation in these tropical birds. Body temperatures were as expected; however, below T(lc) the body temperatures decreased to levels of 35-36 degrees C (T(a)=12 degrees C).
Schleucher
Elke
E
AK Stoffwechselphysiologie, Zoologisches Institut, Johann Wolfgang Goethe-Universität, Siesmayerstrasse 70, D-60323 Frankfurt am Main, Germany. schleucher@zoology.uni-frankfurt.de
D000818:Animals; D001481:Basal Metabolism; D001824:Body Constitution; D001831:Body Temperature; D001834:Body Water / Q000502:physiology; D010856:Columbidae / Q000502:physiology*; D013814:Thermal Conductivity