Starting from a comparison between the Belep Islands (Kanaky New Caledonia) and O’ahu (Hawai’i), this paper aims to contribute to the debates about islands and the Anthropocene, highlighting the relevance of the social and ecological responsibilities deriving from genealogical connections to the islands: ‘the weight of the ancestors’. Considering the implications of these kinds of responsibilities can help to understand human and non-human relational entanglements better so as to value the agentive role of other-than-human perspectives.