Literary trauma theory has traditionally been a humanist concern, and the concept of witnessing, so central to the theorization of trauma, has focused on human experience and relationships. This article stages an interdisciplinary intervention by conceptualizing trans-“species” trauma testimony as a literary encounter involving a double-layered witnessing; the human artist witnessing nonhuman animals’ witnessing to the failings and crises brought about by human society. Focusing on a selection of contemporary Australian poems, a view emerges of poetic witnessing and testimony that (...) exceeds and complicates the sub-genre lenses of old such as “nature poetry,” “ecopoetry,” and “protest poetry.” I propose a new conceptual category that testifies to traumatic structures and consequences of human practices. I explore how this testimony proceeds through a two-way channel of witnessing in which nonhuman animals are active witnessing agents and not merely witnessed by humans. I concentrate on witnessing as primarily experiential, as a corporal, affective operation in which the senses figure centrally. I argue that when poets witness nonhuman animal experience in poetry, testimony advances as an ethical engagement in an act of solidarity and advocacy. Poetry offers productive potential in this respect due to its affinity for engagement with the senses, its capacity to communicate heightened affect, and its scope for expression, articulation, and evocations of meaning outside of conventional sense-making and the limits of rational understanding. (shrink)