OBSERVATIONS ON THE THERMAL CONDUCTANCE OF ADELIE (PYGOSCELIS-ADELIAE) AND HUMBOLDT (SPHENISCUS-HUMBOLDTI) PENGUINS

Analyses of cooling rates in one Adelie and one Humboldt penguin yield ed calculated thermal conductance values of 0.1040 and 0.1672 W(kg deg rees C)(-1), respectively. We review the methods used to calculate pen guin surface area, an important component in calculating conductance v alues, and suggest that, in comparative studies of thermal balance, th e use of body mass is a better estimator of body size than surface are a. Using previously published data on penguin species, we found a sign ificant model to predict thermal conductance from body mass according to: log C = log 0.1083 - 0.474 log M, where C is minimal specific ther mal conductance in W(kg degrees C)(-1) and M is body mass in kilograms .