In the western North Sea, a large seabird assemblage exploits a limited number of fish species. Sandeels are particularly important prey items in this system, with populations that show strong spatial and temporal variability. This variability might be triggered by oceanic climatic features but could also be influenced by human activities, especially fisheries. In order to assess how different sandeel consumers are buffered against fluctuations in prey availability, we studied the foraging energetics of common guillemots, black-legged kittiwakes, European shags and northern gannets at two major colonies in southeast Scotland. Our analysis was based on: (a) time budgets recorded with data loggers attached to breeding adults foraging at sea; (b) metabolic measurements of captive and free-ranging individuals; and (c) information on diet and parental effort. We calculated daily food intake and feeding rates of chick-rearing adults and examined a number of hypothetical scenarios, to investigate how birds might be buffered against reduced sandeel availability. Our results suggest that under the conditions currently operating in this region, shags and guillemots may have sufficient time and energy available to increase their foraging effort considerably, whereas kittiwakes and gannets are more constrained by time and energy respectively. Of the species considered here, gannets are working at the highest metabolic level during chick rearing, and hence, have the least physiological capacity to increase foraging effort. However, to compensate for their energetically costly life, gannets might make use of a highly profitable foraging niche.