Deer allocate their time and use of available habitats to satisfy basic requirements for food, rumination, movement, social interactions, and rest. The majority of the day is spent foraging and ruminating/resting. Seasonal variation in forage quantity and quality is an important driver of these activity budgets: low-quality forage can require a substantial handling time (i.e. rumination), contrary to high-quality forage. Individual differences in nutritional requirements or spatial variation in forage aff ect also activity patterns. Activity patterns reflect changes in the foraging time necessary for large herbivores to meet changing metabolic needs in the face of seasonal and spatial differences in forage quantity and quality. Foraging time influences ind irectly fitness however our understanding of the habitat-performance relationship is still limited. We aim to examine the relationship between habitat use and individual performance in moose at two spatio-temporal scales in two study areas in Norway. Usin g both GPS activity data and measures of individual performances, we want firstly to examine to what extent variations in activity budget are related to variation in plant phenology. The vegetation biomass and quality vary substantially throughout the yea r, we would expect to see similar overall variation in the time spent feeding versus ruminating/resting. Secondly, in addition to temporal variation in the rumination-to-intake ratio we do also expect spatial variation in the rumination-to-intake ratio be tween individuals due to the heterogeneity in available high-quality forage. Thirdly, we want to identify if individual performance at fine scale influence individual performance at larger scale. We predict that moose will have higher reproductive perform ance and body mass in habitats with higher energy gain. This project could be the achievment of long exchanges between the French and the Norwegian labs.