PREDICTIVE GROWTH BUDGETS IN TERNS AND GULLS

• Main Authors: DRENT, RH, KLAASSEN, M, ZWAAN, B
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1992
• Subjects: NESTLING SAVANNAH SPARROWS; ENERGY-EXPENDITURE; NORTHERN GANNETS; METABOLIC RATES; PARENTAL EFFORT; ENERGETICS; CHICKS; FIELD; ECOLOGY; WATER; Arctic; Arctic tern; Common tern
• Online Access: http://hdl.handle.net/11370/882b1b71-dd6d-4005-b9b1-18a50a2e4f7c; https://research.rug.nl/en/publications/predictive-growth-budgets-in-terns-and-gulls(882b1b71-dd6d-4005-b9b1-18a50a2e4f7c).html

Energy budgets for nestling growth are presented for the Sandwich Tern Sterna sandvicensis, Common Tern S. hirundo, Arctic Tern S. paradisaea, and Herring Gull Larus argentatus. Chicks were either raised in captivity (growth efficiencies) or removed from the nest periodically for measurement of basal metabolic rate (BMR). Validation of the laboratory budgets relies on determinations of chick field metabolic rate assessed by the doubly labelled water technique (available for Arctic Tern and one other larid). Comparative analysis suggests that when chicks of these species experience growth rates typical of field conditions avenues of energy allocation summed over the entire period up to fledging show close similarity. Energy used in the production of body tissue averaged 27% (of which 7% for biosynthesis) while BMR accounted for 45%, the remainder being cost of activity and thermoregulation (28%). Where quantified, cost of temperature regulation accounted for only 10% of the total expenditure under field conditions. A regression made of metabolic energy (ME) intake over the entire nestling period against body mass of the fledging based on eight studies of gulls and terns resulted in ME = 35.15.M1.015. This predictive equation also gave satisfying results in non-larids beyond the weight range of the birds studied (100-1000 g).