Document Type

Article

Publication Date

1-1-2002

Publication Title

Journal of Experimental Biology

Volume

205

Issue Number

4

First Page

475

Last Page

483

Disciplines

Biology | Marine Biology

Abstract

We studied the changes in heart rate (HR) associated with metabolic rate of incubating and resting adult wandering albatrosses (Diomedea exulans) on the Crozet Islands. Metabolic rates of resting albatrosses fitted with external HR recorders were measured in a metabolic chamber to calibrate the relationship between HR and oxygen consumption (V̇O2) (V̇O2=0.074×HR+0.019, r2=0.567, P<0.001, where V̇O2 is in ml kg–1 min–1 and HR is in beats min–1). Incubating albatrosses were then fitted with HR recorders to estimate energy expenditure of albatrosses within natural field conditions. We also examined the natural variation in HR and the effects of human disturbance on nesting birds by monitoring the changes in HR. Basal HR was positively related to the mass of the individual. The HR of incubating birds corresponded to a metabolic rate that was 1.5-fold (males) and 1.8-fold (females) lower than basal metabolic rate (BMR) measured in this and a previous study. The difference was probably attributable to birds being stressed while they were held in the metabolic chamber or wearing a mask. Thus, previous measurements of metabolic rate under basal conditions or for incubating wandering albatrosses are likely to be overestimates. Combining the relationship between HR and metabolic rate for both sexes, we estimate that wandering albatrosses expend 147 kJ kg–1 day–1 to incubate their eggs. In addition, the cost of incubation was assumed to vary because (i) HR was higher during the day than at night, and (ii) there was an effect of wind chill (<0°C) on basal HR. The presence of humans in the vicinity of the nest or after a band control was shown to increase HR for extended periods (2–3 h), suggesting that energy expenditure was increased as a result of the disturbance. Lastly, males and females reacted differently to handling in terms of HR response: males reacted more strongly than females before handling, whereas females took longer to recover after being handled.

Comments

This article is licensed under a Creative Commons–Attribution 3.0 Unported license and was originally published in theJournal of Experimental Biology.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.

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