Invasive rats are devastating tropical islands, with effects reaching far beyond the land. Rodents are some of the most difficult invasive species to eradicate, being very adaptable and with a broad diet that can extend from grains and fruits to insects and even chicks. A new study, published in the journal Nature Ecology & Evolution, has revealed that their voracious appetite for young birds is affecting nutrient cycling on tropical islands to such an extent that the oceans around them are also changing.