Ardea
Official journal of the Netherlands Ornithologists' Union

login


[close window] [previous abstract] [next abstract]

Robinson J.A. & Hamer K.C. (2000) Brood size and food provisioning in Common Terns Sterna hirundo and Arctic Terns S. paradisaea: Consequences for chick growth. ARDEA 88 (1): 51-60
Food provisioning rates and chick growth rates of Common Terns Sterna hirundo and Arctic Terns S. paradisaea were studied in Northeast England. Adult terns of both species fed large broods more frequently than those containing fewer chicks. Energy supply per nestling declined slightly as brood size increased and as a result, chicks in large broods developed body mass at a slightly lower rate than those in small broods. Although brood size had no effect on fledging mass in either species, Common Tern chicks from large broods reached fledging mass later than those in small broods. Despite significant effects of brood size, mass growth rate hierarchies did not occur within broods of either species and hatching position had no effect on the mass of fledglings. Brood size and hatching position had no effect on the rate at which chicks developed structurally or on final body size. These results suggest that flexibility of mass growth rates in Arctic and Common Terns may act as a fine-tuning mechanism, allowing parents to increase their annual reproductive output through slower mass growth rates of chicks


[close window] [previous abstract] [next abstract]