Italy eradicated black rats from Zannone in 2007; nine years later, Scopoli's shearwater nesting pairs had nearly tripled from 27 to 80 on the Mediterranean island

Imagine a 1.5-square-mile volcanic rock in the middle of a swimming reef, somewhere between the imagination of a scuba diver and a nesting seabird. Zannone is one of the Pontine Islands near Rome, and for many years it had an unwelcome extra resident: black rats (Rattus rattus), long-time ship stowaways and general pests in the local ecological balance. But in 2007, conservationists removed the offending rodents, and as a result, the island's Scopoli's shearwaters, burrow-nesting seabirds that are vulnerable to the omnivorous predators, have since flourished. Their number jumped from 27 breeding pairs to 80 around the time of the reporting, a rise the 2017 study titled “Island invasives: scaling up to meet the challenge,” by Capizzi et al., in the IUCN's Proceedings of the International Conference on Island Invasives, linked directly to the rat removal.

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