Collapse_ How Societies Choose to Fail or Succeed - Jared Diamond [140]
Instead, the main other component of the Greenland Norse diet was meat of wild animals, especially caribou and seals, consumed to a far greater extent than in Norway or Iceland. Caribou live in large herds that spend the summer in the mountains and descend to lower elevations during the winter. Caribou teeth found in Norse garbage middens show that the animals were hunted in the fall, probably by bow and arrow in communal drives with dogs (the middens also had bones of big elkhounds). The three main seal species hunted were the common seal (alias harbor seal), which is resident all year round in Greenland and comes out on beaches in inner fjords to bear its pups in the spring, at which time it would have been easy to net from boats or to kill by clubbing; and the migratory harp seal and hooded seal, both of which breed in Newfoundland but arrive in Greenland around May in large herds along the seacoast, rather than in the inner fjords where most Norse farms were located. To hunt those migratory seals, the Norse established seasonal bases on the outer fjords, dozens of miles from any farm.
The May arrival of harp and hooded seals was critical to Norse survival, because at that time of year the stocks of stored dairy products from the previous summer and of caribou meat hunted in the previous fall would be running out, but the snow had not yet disappeared from the Norse farms so that livestock could not yet be put out to pasture, and consequently the livestock had not yet given birth and were not yet producing milk. As we shall see, that made the Norse vulnerable to starvation from a failure of the seal migration, or from any obstacle (such as ice in the fjords and along the coast, or else hostile Inuit) that impeded their access to the migratory seals. Such ice conditions may have been especially likely in cold years when the Norse were already vulnerable because of cold summers and hence low hay production.
By means of measurements of bone composition (so-called carbon isotope analyses), one can calculate the ratio of seafood to land-grown food that the human or animal owner of those bones had consumed over the course of a lifetime. As applied to Norse skeletons recovered from Greenland cemeteries, this method shows that the percentage of seafood (mostly seals) consumed in Eastern Settlement at the time of its founding was only 20% but rose to 80% during the later years of Norse survival: presumably because their ability to produce hay to feed wintering livestock had declined, and also because the increased human population needed more food than their livestock could provide. At any given time, seafood consumption was higher in Western Settlement than in Eastern Settlement, because hay production was lower at Western Settlement’s more northerly location. Seal consumption by the Norse population may have been even higher than these measurements indicate, since archaeologists would understandably rather excavate big rich farms than small poor farms, but available bone studies show that people at small poor farms with just a single cow ate more seal meat than did rich farmers. At one poor Western Settlement farm, an astonishing 70% of all animal bones in garbage middens were of seals.
Apart from that heavy reliance on seals and caribou, the Norse obtained minor amounts of wild meat from small mammals (especially hares), seabirds, ptarmigans, swans, eider ducks, beds of mussels, and whales. The latter probably just consisted of the occasional stranded animal; Norse sites contain no harpoons or other whale-hunting equipment. All meat not consumed immediately, whether from livestock or wild animals, would have been dried in storage buildings called skemmur, built of uncemented stones for the wind to whistle through and dry out the meat, and located on windy sites like tops of ridges.
Conspicuously nearly absent from Norse archaeological sites are fish, even though the Greenland Norse were descended from Norwegians and Icelanders who spent much time fishing and happily ate fish. Fish bones