Big Fish & Great Auks: Exploitation of fish & birds on Isle of Portland
Wednesday 16th July 2014
The Isle of Portland is a small peninsula, at only 11km 2, extending off Dorset mainland, which has revealed a small Iron Age and Romano-British settlement. The settlement is contemporary with the well-known Roman town Dorchester, which is situated nearby to the site and probably had close links to the Isle of Portland site itself. Excavations recovered a range of ceramic styles, such as black burnished ware, but also over 13 000 animal bone fragments. Out of the total assemblage, 6% were identified as fish bones, which is actually quite a high significant number in comparison to the even lower numbers found at other contemporary British sites. Bird bones consisted of only 1.4% of the total assemblage but the species identified are highly significant and show different dietary habits to the population of the Isle of Portland to that of nearby Dorchester.
The identification results of the bird and fish assemblage in particular do not only give us information of the dietary habits of the Romano-British population but provide information on how the environment around the Isle of Portland was different in the Roman period in comparison to today. The high abundance of fish bones is significant in itself as in the Iron Age, there were very little marine resources exploited despite the coastal location of many of the sites and it is considered that the later prehistoric population may have a dietary taboo against marine foods. It is only with ever more increasing continental influences and the development of the Roman period that marine food exploitation increases but even for this period, the abundance of fish bones is unusually high. The fish species identified are mostly from large fish species, for example the majority of the Atlantic cod bones found belonged to individuals over a metre long, and nowadays are no longer commonly found in the waters surrounding the Isle of Portland. This indicates that the fishing grounds may have been better back in the Roman period. In addition certain species are now only found in warmer waters, such as around Cornwall, and this suggests that the waters may have also been warmer in the Roman period.
The results of the bird assemblage, although small, have revealed 11 bones of a Great Auk, a bird which went extinct in the mid-19th century due to over-exploitation. It was not previously known when exploitation of this species became popular and there are scarce remains in this area of Britain (most commonly found in Northern Scotland) and within the Roman period itself. The Portland auk evidence has significantly revealed butchery evidence and is the earliest evidence for the exploitation of the species in this period. In addition there were a high number of seabirds exploited at this site which contrasts to the birds exploited at nearby Dorchester and show that the Romano Portland population were using a wider range of nearby resources.
Although what may seem a small amount of fish and bird bones were recovered from the total assemblage, the results are extremely significant for this area and period. Within the report, there are even more important discoveries and results so to read more, please click here.
Image via Flickr user Ewen Foster