Elephant bird bird" egg after it was radiographed. It is widely believed that the extinction of "Aepyornis" was a result of human activity. The birds were initially widespread, occurring from the northern to the southern tip of Madagascar. One theory states that humans hunted the elephant birds to extinction in a very short time for such a large landmass (the Blitzkrieg hypothesis). There is indeed evidence that they were hunted and their preferred habitats destroyed. Eggs may have been particularly vulnerable. 19th-century travelers saw eggshells used as bowls, and a recent archaeological study found remains of eggshells among the remains of human
Norfolk Island on the island and is now extinct, but the taxonomic relation of this is unclear, and has not been scientifically described yet. 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. Norfolk