The present study will establish a link between the mercury levels in the abiotic environment (e.g. historical records of mercury data in peat bogs, the ice sheet or marine sediments) with levels in carnivore species (polar bear, birds of prey). These results can be used in a model for predicting past and future development of the mercury loads in high trophic biota. This in turn will enable us to evaluate if changes in mercury levels in the atmosphere are reflected in species at higher trophic levels of the Arctic ecosystem. The project will expand the longevity and certainty of the biotic time series of mercury to about 150 years by analyzing museum samples of bird feathers and polar bear hair and teeth. The project is part of the project “Fate of mercury in the Arctic (FOMA)”.