Plasma metabolites of 30 bird species during active migratory endurance flight

Plasma metabolites of the fat-, protein and carbohydrate metabolism were analysed in 30 species of migrant passerines on a Swiss Alpine pass, Col de Bretolet. Birds were caught in high mist nets out of their flight; hence the plasma metabolites reflect the metabolism of a flying, fasting bird. The metabolic profile was compared with post-flight birds held in a cloth bag for at least 1 hour.