Energy expenditure in free-living kittiwakes in Kongsfjorden , Svalbard, has been estimated by doubly labeled water method (DLW) during 9 years since 1998. This is the longest available dataset for any free-living bird species. Long-term datasets are espe cially important in rapidly changing environments such as the Artic. The aim of this study is two-fold. First, we intend to continue our long-term dataset on energy expenditure that will help us to understand the energetic response of kittiwakes to changi ng conditions in the Arctic. Second, we will make use of newly developed bio-logging technology, externally attached miniature accelerometers. These data will allow us to determine differences in activity levels between individual birds, presumably a powe rful predictor of energy expenditure in seabirds. It will also enable us to derive a second, independent estimate of energy expenditure and evaluate its potential to replace the more invasive DLW method in the future.