Species living in the Arctic are facing strong environmental changes. Forecasting impacts of such changes on endemic Arctic species require a full understanding of their ecology and habitat requirement. A limited number of sea ice associated Arctic species act as sentinel species, whose ecological responses to the consequences of environmental modifications deserve special attention and can set an example for all Arctic biota. This is the case of the ivory gull (Pagophila eburnea), a species that entirely completes its lifecycle in the Arctic and is thus directly facing impacts of the Arctic alteration. In an initial phase of our program, we proposed to use complementary approaches to investigate the demographic trend, change of space use and contaminant load of Arctic species under climate change and other environmental modifications (i.e. an increase of bird exposure to contaminants), with ivory gull as case study species. In the 2-year previous phase of our project, (i) we combined genetic and genomic information (high-throughput sequencing) to infer recent demographic trajectory and genomic structure of populations, (ii) we modelled breeding colonies distribution related to climatic conditions, and (iii) we used GPS tracking to infer movements and habitat selection of ivory gull during the breeding period. We also preliminary investigated the contaminant loads of ivory gulls in its last Greenlandic breeding strongholds in relation with its trophic position. Building on results obtained, we wish in this second phase to continue this endeavor by improving and increasing sampled information to specifically answer some unanswered question and to develop new ones. Overall the complementary approach we developed in this program should produce fundamental biological information for the conservation of the ivory gull in the context of climate change and of the planned exploitation of its offshore feeding grounds.