Abstract
Some invasive species threaten native species because they possess traits to which natives are evolutionarily naïve. In Australia, many predators have been severely impacted by the introduction of cane toads, which produce toxins that native species have never encountered. Torresian crows, however, have been observed consuming cane toads safely by avoiding their toxin glands, suggesting learned behavioural adaptations. To investigate this, we used baited camera stations to test whether wild crows with 1–10 years exposure to cane toads consumed toads differently compared to non-toxic native frogs. Crows were presented with four prey types: native frogs, intact toads, toads with toxin glands removed, and toads with toxin glands removed but toxin reapplied. In all trials with native frogs and toads lacking toxin glands, crows consumed the entire prey item, correctly recognising them as non-toxic. With intact toads, crows consumed only non-toxic parts in 89% of trials, demonstrating strategies to safely exploit this toxic prey. When toxin glands were removed but toxin reapplied, crows consumed only non-toxic parts in 58% of trials, suggesting that some individuals may rely on the presence of toxin glands as a visual cue of toxicity. These findings provide clear evidence of behavioural flexibility in Torresian crows, highlighting their capacity to rapidly adapt to novel threats posed by invasive species.