After the mainland herds were gone

The last mammoths

They were still in their heyday 20,000 years ago but within 10,000 years they were reduced to isolated populations off the coasts of Siberia and Alaska. Natural History Museum By 4,000 years ago they were gone. Natural History Museum

Woolly mammoths died out on the mainland a little later, around 10,500 years ago. But populations survived on the islands left behind after the Bering land bridge was swallowed by the sea. Natural History Museum On Alaska’s St Paul Island, they lasted until 5,600 years ago and, further north, on Wrangel Island until 4,000 years ago. Natural History Museum

Scientific evidence suggests that small populations of woolly mammoths may have survived in mainland North America until between 10,500 and 7,600 years ago. Britannica Other evidence suggests that woolly mammoths persisted until 5,600 years ago on St. Paul Island, Alaska, in the Bering Sea and as late as 4,300 years ago on Wrangel Island, an Arctic island located off the coast of northern Russia, before succumbing to extinction from inbreeding and loss of genetic diversity. Britannica

But hardly anyone had doubted, that paper says, that mammoths had become extinct everywhere by around 9,500 years before present (BP). New discoveries on Wrangel Island in the Arctic Ocean forced that view to be revised. Nature, 1993 Along with normal-sized mammoth fossils dating to the end of the Pleistocene, numerous teeth of dwarf mammoth dated 7,000-4,000 yr BP have been found there. The island is thought to have become separated from the mainland by 12,000 yr BP. Nature, 1993 Survival of a mammoth population may be explained, the authors say, by local topography and climatic features, which permitted relictual preservation of communities of steppe plants. They interpret the dwarfing of the Wrangel mammoths as a result of the insularity effect, combined with a response to the general trend towards unfavourable environment in the Holocene. Nature, 1993

Humans didn’t get there until very late, Lister says. We are almost 100% certain that there were no people on St Paul until the eighteenth century or so. Five and a half thousand years ago, there were drought conditions and limited freshwater, and that’s probably what drove them extinct. Natural History Museum

On Wrangel, the first signs of humans on the island come only a few hundred years after the last mammoth fossils. There is a question of whether the mammoth population was hunted to extinction or was already gone by the time people got there. There is evidence of people hunting marine mammals like seals, but no evidence they were hunting mammoths. Natural History Museum The Museum also has not identified any significant environmental change on Wrangel about 4,000 years ago. There’s nothing obvious in climate or vegetation. It is possible that genetic mutations in this small and isolated population may have led to poor health and ultimately extinction. Natural History Museum An examination of a fossil tooth discovered in 2015 indicated that a tiny population of mammoths persisted on Wrangel Island, an Arctic island located off the coast of northern Russia, as late as 4,300 years ago before succumbing to extinction from the effects of inbreeding and the loss of genetic diversity. Britannica

The wider argument about climate and hunting, on the mainland as well as on the islands, is on the extinction page.