The Metabolic Rate of Tropical Birds

Abstract

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High Levels of Energy Expenditure in Shorebirds; Metabolic Adaptations to an Energetically Expensive Way of Life

“…The majority (28 out of 49 measurements) differed by more than 20% from the predicted values; the extremes being 69% of the predicted value in the Magnificent Frigatebird Fregata magnijicens (1078 g) and 200% in the Glaucous Gull Larus hyperboreus (1200 g). Much of this variation around predicted levels can be related to geographic distribution, as was already shown for terrestrial birds by Weathers (1979) and Hails (1983). Among 16 species of Charadriiformes (mainly Laridae) the ratio between measured and predicted BMR increased from 0.8 in the tropics to 1.8 in arctic breeding species (Ellis 1984).…”

Slow pace of life in tropical sedentary birds: a common-garden experiment on four stonechat populations from different latitudes

“…Indeed several studies, particularly in birds, have suggested that metabolic rates increase with latitude (Kendeigh 1944;Kendeigh & Blem 1974;Ricklefs 1976;Vleck & Vleck 1979;Weathers 1979;Bryant & Hails 1983;Hails 1983;Klaassen et al 1989;Klaassen & Drent 1991;Klaassen 1995;Weathers 1997). However, latitude was not the only factor affecting metabolic rate in these studies.…”

Acclimation to different thermal conditions in a northerly wintering shorebird is driven by body mass-related changes in organ size

“…BMR is a highly flexible phenotypic trait (Piersma, 2002) and varies both with season (Aschoff and Pohl, 1970;Cooper and Swanson, 1994;Piersma et al, 1995;Liknes and Swanson, 1996;Kvist and Lindström, 2001;Cooper, 2002;Liknes et al, 2002) and geographic location (Weathers, 1979;Kersten et al, 1998;Kvist and Lindström, 2001;Broggi et al, 2004). Several studies showed higher levels of BMR at high latitudes, either within migratory species alternating between tropical and arctic climates, or interspecifically when comparing sedentary species (Weathers, 1979;Hails, 1983;Kersten et al, 1998, Kvist andLindström, 2001;Tieleman and Williams, 2002;Tieleman et al, 2003;Broggi et al, 2004). It is not clear, however, whether an increase in BMR would actually contribute to improved cold tolerance or simply reflect the physiological upregulation necessary to tolerate prolonged periods of cold.…”