Environmental DNA sampling as a surveillance tool for cane toad Rhinella marina introductions on offshore islands

Abstract

Containing the spread of established invasive species is critical for minimizing their ecological impact. Effective containment requires sensitive sampling methods capable of detecting new introductions when invaders are at low density. Here we explore whether environmental DNA (eDNA) sampling could be used as a surveillance tool to detect new incursions of aquatic invasive species on offshore islands. We develop an eDNA molecular assay for invasive cane toads (Rhinella marina) in Australia, validate our assay on the mainland, and apply it to an offshore island (Moreton Island) that is a target of ongoing cane toad surveillance. Our eDNA assay correctly identified four mainland sites at whic..