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The Norfolk Island Group Nepean Island is also home to breeding seabirds. The providence petrel was hunted to local extinction by the beginning of the 19th century, but has shown signs of returning to breed on Phillip Island. Other seabirds breeding there include the white-necked petrel, Kermadec petrel, wedge-tailed shearwater, Australasian gannet, red-tailed tropicbird and grey ternlet. The sooty tern (known locally as the whale bird) has traditionally been subject to seasonal egg harvesting by Norfolk Islanders.

What other types of petrels are extinct on Phillip Island?
unanswerable