Animal husbandry in the Viking Age town of Birka and its hinterland : excavations in the black earth 1990-95

Sammanfattning: The Birka Excavations 1990-95 provided a unique opportunity to excavate a Swedish Viking Age town stratigraphically, allowing the finds - including extensive and well-preserved faunal remains - to be dated accurately. This in turn has given the opportunity to study the nature and development of Viking Age animal husbandry in a new, closer perspective.The Birka bones form the most comprehensive osteological assemblage recovered from a Swedish Viking Age site to date. Their osteological analysis, together with the study of bones from other contemporary sites, has answered many questions that could previously not be resolved. Hitherto very little was known of animal husbandry, meat production, trade in animal-based foodstuffs and patterns of meat consumption in early medieval Sweden.Birka's life spanned at least 225 years (AD 750-975), during which time the town functioned as a highly important trading centre in which many merchants and craftsmen lived and worked. The excavations 1990-95 yielded 6 tonnes of bones, consisting mainly of food and butchery waste, from two of the town's tenement plots. The assemblage comprises primarily the bones of domesticates such as cattle, pig and sheep, together with a sizeable proportion of bird and fish bones; numerous bones from a variety of wild species are also included. A 600kg sample of the mammal bones was selected and analysed using modern osteological techniques.Among its findings the analysis reveals a clear change in the pattern of meat consumption during the Viking Age in Birka and its hinterland. Sheep predominate amongst the bones of domesticates in the earliest town deposits. However, after the mid-9th century sheep numbers decline rapidly at the same time as cattle consumption increases. Pig numbers remain roughly constant throughout the stratigraphic sequence. Studies of contemporary assemblages in Central Sweden have revealed a similar sequence of events.Age and sex assessments of the bones of domesticates have provided important evidence for interpreting animal husbandry in Birka and its surrounding area. A synthesis of the cattle data suggests an emphasis on dairying in the town's hinterland. Viking Age sheep husbandry, on the other hand, appears not to have been specialized; various products were obtained throughout the course of an animal's life: first wool and milk, and finally meat. Surplus cattle and sheep were sold to Birka and slaughtered there. Many of the pigs slaughtered in Birka were most likely reared in the town.The importance of fur trading and pelt processing for Birka is evident from the substantial numbers of bones from a variety of fur-bearing animals yielded by the excavations. The majority of these bones derive from the paws, which were left attached to the pelt until final processing and tanning in the town, at which point they were detached and discarded amongst the urban refuse. The commonest fur-bearing animals were the fox, squirrel and marten. Fur trading and pelt processing appear to have been important to Birka from the town's earliest beginnings until its final abandonment.