Garthe, Stefan, Ludynia, Katrin, Hueppop, Ommo, Kubetzki, Ulrike, Meraz, Juan F. and Furness, Robert W. (2012) Energy budgets reveal equal benefits of varied migration strategies in northern gannets. Marine Biology, 159 (9). pp. 1907-1915. DOI 10.1007/s00227-012-1978-6.

Full text not available from this repository.

Abstract

We investigated migration and wintering of adult northern gannets (Morus bassanus) breeding in east Scotland, North Sea, by deploying geolocation loggers over three winters. The wintering ranges of these birds varied from the North Sea to the Atlantic off West Africa. Flight time was taken as a proxy for migration and foraging effort. Gannets wintering off Africa had higher total flight times during migration than birds wintering further north. Total flight times in different wintering regions were generally low. Birds off West Africa consistently spent < 25 % of daylight hours in flight, but birds further north showed more variable values that may reflect more variable weather or food availability. Winter sea surface temperatures ranged from 9 °C (North Sea) to 16 °C (West Africa). Thermostatic costs in winter as estimated by measuring thermal conductance in carcasses in still air and water were 28 % higher in North Sea than off West Africa. This effect is aggravated by higher thermostatic costs caused by stronger wind chills in the North Sea compared to the conditions off West Africa. Birds wintering close to the UK arrived at the colony on average 12 days earlier than birds wintering off West Africa. We conclude that the net cost-benefit analysis may be similar for all wintering areas investigated.

Document Type:	Article
Keywords:	Basal Metabolic Rate, Flight Activity, Daylight Period, Wind Chill, Daily Energy Requirement
Research affiliation:	OceanRep > The Future Ocean - Cluster of Excellence Kiel University
Refereed:	Yes
Open Access Journal?:	No
Publisher:	American Medical Association
Projects:	Future Ocean
Date Deposited:	14 May 2014 10:08
Last Modified:	31 Jul 2019 06:37
URI:	https://oceanrep.geomar.de/id/eprint/23987

Actions (login required)

View Item