Energetics equations and food consumption of seabirds in two marine upwelling areas: Comparisons and the need for standardization

Abstract

Estimates of daily energy expenditure (DEE) are used to calculate the quantity of food consumed by populations of seabirds. Estimates of DEE and food consumption resulting from four energetics equations for three common species of seabirds in each of the Humboldt and Benguela upwelling regions off Peru and South Africa are compared. Differences in the estimates of DEE were minor, but differences between maximum and minimum estimates of food consumption by seabirds amounted to 4,4 per cent of the total Peruvian and 1,6 per cent of the southern African commercial anchovy catches in 1978. The most conservative energetics equation and a degree of standardization of estimates of DEE are recommended for use in future studies of food consumption or community energetics. © 1984 Taylor & Francis Group, LLC.