The Work

Specialist Report 2005 - Fish Bone and Marine Mollusc Report

Posted by steven on 05/04/2006 at 07:18 PM

ANALYSIS OF FISH BONE AND MARINE MOLLUSCS

Ruby Cerón-Carrasco - University of Edinburgh

Methodologies

The fish remains from High Pasture Cave were recovered from Trench 1, 2 and 6. Six contexts contained fish remains that were retrieved by sieving. All the remains were identified to species level; this was done by reference to a modern fish bone collection and to standard guides (Watt et al 1997). Nomenclature follows Wheeler & Jones (1989, 122-123).

All elements were examined for signs of butchery and burning. The colour of burnt bone was recorded to allow investigation into the nature of burning, i.e. cooking, rubbish disposal, etc. The sizes of the Gadidae, are given as an approximate size range, this is done by matching the archaeological material to modern fish skeletons of known size based on ‘total body length’. Therefore, the elements from saithe skeleton (the only species recovered from this family) were categorized as ‘ very small’ (< 15 cm in length). For the non-gadoid species a classification of either 'juvenile' or 'adult' was made by comparison to modern species.

The recording of preservation state of the fish bone was based on two characters: texture on a scale of 1 to 5 (fresh to extremely crumbly) and erosion also on a scale of 1 to 5 (none to extreme). The sum of both was used as an indication of bone condition; fresh bone would score 2 while extremely poorly preserved bone would score 10 (after Nicholson 1991).

The marine molluscs from High Pasture Cave were recovered by sieving and by hand-collection during the excavation. A total of eight contexts from Trench 2 and 6 contained marine molluscs. The apical fragments of shell were identified to species using standard guides (Campbell & Nicholls1989, Moreno-Nuño 1994a). Frequency was estimated by counting shell apices for gastropods and valve umbos for bivalve species (Moreno-Nuño 1994b). Broken fragments were scanned and an approximate quantification has been given to give a general idea of the presence and importance of the different species found in the assemblage. The species were then quantified in terms of their relative frequency within each sample. Burnt shell was noted and recorded as such.

Fish remains: Results

The material was found to contain quite eroded and very fragile fish bone. Their condition score was generally in the range of 7-8 indicating extremely poorly preserved bone. Skeletal elements were most frequently 60-70 % complete. Some elements from Trench 2 and 6 were burnt probably a result of domestic rubbish disposal.

A total of five taxa were identified to species. The assemblage has a varied representation of mainly marine fishes. The main group represented in the assemblage was herring (Clupea harengus). Other marine species recovered included saithe (Pollachius virens), mackerel (Scomber scombrus), remains of a species of tuna, possibly Skipjack tuna (Euthynnus cf pelamis) and remains of salmon (Salmo salar) were also recovered.

The marine molluscs: Results

Edible periwinkles (Littorina littorea) are found on rocks, stones and seaweed on the middle and lower shores.
The limpet Patella vulgata, was also common and is found throughout the Scottish coast on all rocky shores. The limpet (Patella vulgata) is a species of major importance in quantitative terms on most littoral shores and in shallow waters (Branch 1985).

Common mussel (Mytilus edulis) is found on stones and rocks in estuaries and on exposed shores on rocks often in extensive beds associated with barnacles. Mussel is fragile and it is usually recovered mainly as broken fragments. Most of the mussel shell recovered at High Pasture Cave consisted of broken shell fragments.
The common oyster (Ostrea edulis) is found mainly on shallow water; its shell like that of mussel is also very fragile. The oyster shell recovered at High Pasture Cave was very fragmentary due to its lamellar structure.
Fragments of scallop shell were recovered mainly fragments of Great scallop also known as St. James’ Shell (Pencten maximus) which are found on sand and gravel, usually in quite deep water.

The common whelk (Buccinum undatum) was also recovered, this species is found in shallow water on sand and mud, as well as the common otter shell (Lutraria lutraria) which was also present in this assemblage.

Conclusions

The fish remains recovered from the 2005 excavation at High Pasture’s Cave are considered to be the remains derived from fish species that were caught by humans to be consumed on site. Trench 6 produced the most abundant and most diverse fish element and species representation.

Herring was the main species represented, their presence indicate that boats and nets may have been used for catching these although they can occasionally be caught on line and, since at least the 16th century, their catch was also done close inshore using trap-nets (also known as stake-nets or herring baulks) or weirs; similarly close inshore by boat with net would have been sufficient to ensure a good catch.

Fishing from rocks would have produced young saithe. The use of boats and hand-lines would have been required for the catch of adult mackerel and the Skipjack tuna. The presence of a species of tuna is quite significant since these species are normally found in temperate waters and is rarely seen in northern European seas; however the wide range and habit of migrations of the Skipjack tuna, means that this species may occur in this region than any other species of tuna fishes.

Fish belonging to the salmon was also present; these can be easily caught using wicker traps in freshwater streams or on coastal waters also using lines

Similarly, it is likely that most of the marine molluscs recovered at High Pasture Cave were originally gathered as foodstuff; all the shells recovered were from edible species. Those traditionally used for fish-bait such as limpets, periwinkles and mussel were also present, particularly the periwinkle that has traditionally been used as food and as fishing bait, this was the most abundant species of marine molluscs present, particularly so in Trench 6. Shells recovered from the two trenches (2 and 6) contained burnt shell remains which like the burnt fish remains are considered to be the remains of domestic rubbish disposal.

References

Campbell, A.C. & Nicholls, J. 1989 Seashores & Shallow Seas of Britain and Europe. Ondon: Hamlyn Guides.

Moreno-Nuño, R. 1994a Arqueomalacología. Identificación de Moluscos. Informe no. 1994/18. Laboratorio de Arqueozoologia.Madrid: Universidad Autónoma de Madrid.

Moreno-Nuño, R. 1994b Arqueomalacología. Cuantificación de Moluscos. Informe no. 1994/19. Laboratorio de Arqueozoologia. Madrid: Universidad Autónoma de Madrid.

Nicholson, R.A. 1991 An investigation into variability within archaeologically recovered assemblages of faunal remains: The influence of pre-depositional taphonomic processes. D. Phil. Thesis. University of York.

Watt, J., Pierce, G. J. & Boyle, P. R. 1997 ‘Guide to the Identification of North Sea Fish using Premaxilla and vertebra’. ICES. CooperativeResearch Report No. 220. Denmark.

Wheeler, A. 1969 The fishes of the British Isles and North-West Europe. Macmillan. London.

Wheeler, A. 1978 Key to the fishes of Northern Europe. London: Frederick Warne.

Wheeler, A. & Jones, A. K. J. 1989 Fishes. Cambridge Manuals in Archaeology. Cambridge University Press.


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