Most people believe that suffering is intrinsically bad. In conjunction with facts about our world and plausible moral principles, this yields a pro tanto obligation to reduce suffering. This is the intuitive starting point for the moral argument in favor of interventions to prevent wild animal suffering. If we accept the moral principle that we ought, pro tanto, to reduce the suffering of all sentient creatures, and we recognize the prevalence of suffering in the wild, then we seem committed to (...) the existence of such a pro tanto obligation. Of course, competing values such as the aesthetic, scientific or moral values of species, biodiversity, naturalness or wildness, might be relevant to the all-things-considered case for or against intervention. Still, many argue that, even if we were to give some weight to such values, no plausible theory could resist the conclusion that WAS is overridingly important. This article is concerned with large-scale interventions to prevent WAS and their tractability and the deep epistemic problem they raise. We concede that suffering gives us a reason to prevent it where it occurs, but we argue that the nature of ecosystems leaves us with no reason to predict that interventions would reduce, rather than exacerbate, suffering. We consider two interventions, based on gene editing technology, proposed as holding promise to prevent WAS; raise epistemic concerns about them; discuss their potential moral costs; and conclude by proposing a way forward: to justify interventions to prevent WAS, we need to develop models that predict the effects of interventions on biodiversity, ecosystem functioning, and animals’ well-being. (shrink)