Field and laboratory metabolism and thermoregulation in Dovekies (Alle alle)

Abstract

ABsTRAcr.-The Dovekie (Alle alle) is an abundant seabird in the high Arctic. We studied Dovekie energetics by measurements of resting metabolic rate (RMR) in the laboratory and rates of CO2 production (with doubly labeled water, DLW) of free-living adults during the chick-rearing period. Within the thermoneutral zone, resting metabolism was 2.42 ? 0.13 ml O2 g'h-' (177.9 ? 9.6 kJ/day). These values were 84-112% greater than predicted for nonpasserines. Thermal conductance (C) was 0.0630 ? 0.0029 ml 02 g'h-' 0C-', which was close to or lower than allometric values of birds of similar body size. Field metabolic rate (FMR) was 6.68 ? 1.06 mlC02 C gh-' (696.1 ? 103.7 kJ/day). This is the highest FMR value, corrected for body mass, yet published for seabirds studied by the doubly labeled water method during the chick-rearing period. The high wing loading of Dovekies implies that flight cost may be high, resulting in a high FMR. Despite a high FMR, Dovekies had an FMR/RMR ratio of 3.9, similar to values reported for other species in other regions during chick-rearing. We estimated that the amount of plankton (mainly Calanus finmarchicus) consumed each day by Dovekies equaled 80% of their body mass. A colony of 70,000 pairs of Dovekies (assuming one 14-day-old chick in each nest) would consume 21.9 tons of fresh zooplankton per day, and would add approximately 2.1 tons (dry mass) per day of guano to the marine and terrestrial ecosystems over this period. Received 4 January 1990, accepted 13 July 1990.