BASAL METABOLIC RATES OF MIGRATING WADERS IN THE EURASIAN ARCTIC

I measured the basal metabolic rate (BMR) of 24 juvenile waders of 5 s pecies (Little Stint Calidris minuta, Dunlin C. alpina, Sanderling C. alba, Curlew Sandpiper C. few ferruginea and Turnstone Arenaria interp res) during the first part of their southward migration along the Arct ic coast of Eurasia. The average BMR was in general higher than the BM R of birds of the same species on wintering grounds in Africa. This su pports the hypothesis that BMR can vary seasonally in migratory birds, possibly reflecting adaptive seasonal changes in the size of the bird 's metabolic machinery.