Résumé : This comparative reading of contemporary Australasian and Canadian fiction privileges a reciprocal interaction between ecocriticism and magic realism within the field of postcolonial studies. My research shows that few works examine magic realism as a distinct aesthetic mode, while many ecocritical and postcolonial studies favour colonialist and pessimistic perspectives. Seeking to balance thematic and aesthetic concerns, my concepts of ecological magic realism and magic realist ecopoetics re-evaluate this still often misunderstood mode: its techniques in postcolonial narratives not only transcribe the cultural plight of the postcolonial subject, but also translate the missing ecological link between the environment and human beings. Informed by ecopoetic reflections on figurative language, Delbaere-Garant’s notion of mythic realism, and material ecocriticism, my concepts take the narrative and physical agency – or poiesis – of the non-human world as their focal point. Recognizing the dialogical web of human and non-human energies raises the issues of eco-imperialism as well as those of environmental and social justice. My thesis discusses two main configurations of ecological magic realism common to Anglo-Celtic and Indigenous texts within my corpus: synergy and crisis. These shifting interspecies relations are explored through the contexts of eco-spiritualities, scientific approaches to Nature, Nature writing, gothic-like metamorphoses, eco-apocalypse, and the Anthropocene. Rejecting dualistic worldviews, magic realism in these collaborative or competitive humans/Nature interactions remains ambivalent: on the one hand, it re-enacts human beings’ failed embeddedness in their non-human surroundings; on the other, it also re-opens the possibility of a mutually-enriching symbiosis.