Coastal fish weir at the northern end of The Nass

Reasons for Designation

Coastal fish weirs are artificial barriers created within the inter-tidal zone, using stone walls, wattle or timber fencing to channel fish into traps. The most common form of weir (a term derived from `were' - an Anglo-Saxon word meaning fish trap) is a simple `V'-shaped arrangement of walls, frequently 100m or more in length. Baskets or nets would be placed at the point of the `V' which would normally be orientated seaward so as to draw in the fish with the receding tide. Weirs may also be rectangular or more linear in appearance with traps located either in corners or set within spurs attached to the main walls. Placed in gently shelving coastal or estuarine locations, the weirs would become sufficiently exposed at low water for the fish to be collected and, in some instances, for initial processing (gutting, filleting) to take place on site. Stationary fish traps are known to have been used since the Mesolithic period, although the earliest examples to leave strong visible traces around the coastline belong to a tradition dating from the early medieval or Anglo-Saxon period. Documentary evidence from the 10th century onwards suggests that fish weirs were largely the preserve of the upper echelons of medieval society, maintained either by larger manors or by religious houses. In addition to the obvious advantage of a constant food supply, the produce from the fish weirs provided economic benefit, indicated social status and could aid compliance with the religious dietary strictures of the period. Large fish weirs were still used in the Severn Estuary until the early 20th century, and their small-scale use persists here and in other parts of the British Isles to this day. In general, however, the practice reached its peak between the 12th and 14th centuries, hereafter declining in the face of growing commercial sea fishing. The remains of about 500 fish weirs are estimated to survive around England's coast. Those of medieval or earlier date which demonstrate a high degree of preservation, and particularly those which form groups or have demonstrable links with manorial or ecclesiastical estates, will normally be considered to be of national importance and worthy of protection.

Inspection at ground level has shown the weir at the northern end of The Nass to be in a good state of preservation; the upright timbers survive well and there are several areas of hurdling still extant. The timber post alignments show the overall layout of the weir and provide clear evidence for its original design and the manner in which it operated. Radiocarbon dating gives a date range for the monument of AD 664-882, providing a direct parallel with the coastal fish weir at Sales Point, which has also been radiocarbon dated to AD 656-957,the Middle Saxon period. Documentary evidence concurs with the radiocarbon dating: the Domesday Book lists a fishery at Tollesbury, almost certainly referring to the weir at The Nass.

Details

The monument includes a substantial coastal fish weir located at the mouth of Tollesbury Fleet, some 600m south east of Old Hall Marshes. The timber weir was first recorded at ground level by Mr Ron Hall, a local amateur archaeologist, in January 1993, and was subsequently photographed from the air by Steve Wallis of the Archaeological Advisory Group of Essex County Council. It is a V-shaped timber weir with walls measuring 120m (north east to south west) and 130m (north-south) converging to the north east, where a long narrow structure also of upright timbers forms an elongated trap area. Evidence for various phases of construction and repair can be discerned; the southernmost wall appears to have at least two phases of rebuilding at slightly different angles. The walls are constructed using upright timbers infilled with panels of hurdling; the latter, in addition to forming the infill for the walls of the weir, may have formed a walkway along the walls in order to allow access to the fish trap areas of the structure. Some of the large timbers from the site have features such as mortice holes and tenons. Samples of the timbers were taken for radiocarbon analysis and gave a date range of AD 664-882. As with several other timber fish weirs constructed in the estuary in the Anglo-Saxon or medieval period, it was clearly designed to exploit the action of the tides in the inter-tidal zone of the day.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 10 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

32404

Legacy System:

RSM

Sources

Books and journals
Strachan, D, C14 dating of some inter-tidal fish-weirs in Essex, (1997)
Rumble, A (ed.), Domesday Book, (1983)

Other
Strachan, D, TL91SE 1:10000, (1996)
Fourteen black-and-white prints, Pearce, B, Unreferenced - ESMR number 9974 only, (1993)
Two colour prints; three b/w prints, Bruce, K, KBC 8,9; KBBW 27,28,29, (1993)
One colour print, Austin, L, BESP Film 3 Frame 24, (1993)
Three black-and-white prints, Strachan, D, BW/1994/1/9,, (1994)
Two colour prints, Strachan, D, CP/96/41/1, (1996)
Eleven colour prints from slides, Hall, R, Unreferenced - ESMR number 9974 only, (1993)
Two colour prints, Strachan, D, CP/97/5/11, (1997)
One black-and-white print, Rogers, P, SWBW14-3, (1993)

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