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Trophic interactions between threatened species complicate management. Similarly, interactions between threatened species and pest species present management challenges, given that pest control can lead to non-target impacts (eg, trophic cascades or secondary poisoning). There are records of the Critically Endangered Norfolk Island Morepork Ninox novaeseelandiae undulata consuming both threatened songbirds and invasive rodents that are subject to management interventions. Despite this, the frequency at which vertebrate prey are consumed, and the dietary breadth of the morepork, remain largely unknown. Regurgitated pellets were visually screened using a microscope, alongside environmental DNA (eDNA) screening of pellets and scats, to investigate the diet of the Norfolk Island Morepork. Eighty-nine pellets were collected from six owls between October 2020 and January 2021. Twenty-four pellets and 19 scats were collected from five owls between May and June 2021. All moreporks screened with eDNA metabarcoding had consumed invasive rodents and at least one third of samples contained rodents. Moreporks were also found to have consumed four of five endemic songbirds and an endemic parrot, most of which are threatened. Environmental DNA metabarcoding detected more taxa overall, but visual screening identified a greater richness of Orthoptera and Coleoptera in the diet of the morepork. The frequency with which the Norfolk Island Morepork consumed rodents presents a conundrum for conservation managers. Control of invasive rodents is considered essential to support threatened songbirds, yet this same …