Details

This monument includes a vermin trap situated amongst earlier tin
streamworking earthworks within the Blacka Brook valley bottom. The vermin
trap includes two lengths of partly faced drystone walling, together forming a
`V'-shaped trap pointing towards an earlier boundary wall. The position of the
trap suggests that the boundary wall was intended to help encourage the vermin
into the trapping area which was originally sited at the point where the walls
converge. The location of the trap suggests that it was designed to capture
vermin using the river for access into the warren. The trapping area survives
as a 1.7m wide gap between all three walls. The northern arm of the trap
measures 8m long, 1.4m wide and 0.7m high, whilst the ENE arm is 5m long, 2m
wide and 0.7m high. The faced rubble boundary wall, reused by the warreners as
part of this trap, measures 2m wide and up to 0.8m high.
Vermin approaching their quarry tend to seek a route that provides visual
cover, and the purpose of a trap was to funnel predators along ditches or
beside walls to a central point where they could be trapped.
This vermin trap forms part of Trowlesworthy Warren, which includes around
64 pillow mounds and 40 vermin traps scattered along the slopes of Little and
Great Trowlesworthy Tors. The boundaries of the warren are denoted by the
River Plym, Spanish Lake and Blacka Brook. Trowlesworthy Warren is generally
accepted as the oldest surviving warren on Dartmoor, although recently doubt
has been expressed concerning its medieval origins. However, it is known that
the warren existed by 1651 when it was occupied by John Hamblin, a skinner
from Plymouth. The warren appears to have remained in constant use from this
time until the first half of the 20th century.
The streamwork earthworks and length of boundary wall below and within 2m of
the trap are included in the scheduling.
This monument is in the care of the Secretary of State.

MAP EXTRACT
The site of the monument is shown on the attached map extract.
It includes a 2 metre boundary around the archaeological features,
considered to be essential for the monument's support and preservation.

Source: Historic England

Reasons for Scheduling

Dartmoor is the largest expanse of open moorland in southern Britain and,
because of exceptional conditions of preservation, it is also one of the most
complete examples of upland relict landscape in the whole country. The great
wealth and diversity of archaeological remains provide direct evidence for
human exploitation of the Moor from the early prehistoric period onwards. The
well-preserved and often visible relationship between settlement sites, major
land boundaries, trackways, ceremonial and funerary monuments as well as later
industrial remains, gives significant insights into successive changes in the
pattern of land-use through time.
Warrens are areas of land set aside for the breeding and management of rabbits
or hares. They usually include a series of purpose-built breeding places,
known as pillow mounds and buries, vermin traps and enclosures designed to
contain and protect the animals, and living quarters for the warrener who kept
charge of the warren.
Pillow mounds are low oblong-shaped mounds of soil and/or stones in which the
animals lived. They are usually between 15m and 40m long and between 5m and
10m wide. Most have a ditch around at least three sides to facilitate
drainage. Inside are a series of narrow interconnecting trenches. These were
excavated and covered with stone or turf before the mound was constructed.
Vermin traps of various kinds are found within most warrens. These include a
small stone-lined passage into which the predator was funnelled by a series of
ditches or walls. Over 100 vermin traps have been recorded on the Moor, with
the majority lying in the Plym Valley.
Warren boundaries were often defined by a combination of natural features such
as rivers. Within the warrens themselves smaller enclosed areas defined by a
ditch and bank are sometimes found, and some of these may have been
specialised breeding areas. Many of the warrens on the Moor contain a house in
which the warrener lived.
Most of the surviving warren earthworks probably date to between the 17th
century and the later 19th century, with some continuing in use into the early
20th century. At least 22 warrens are known to exist on the Moor and together
they contribute to our understanding of the medieval and post-medieval
exploitation of the area. All well-preserved warrens are considered worthy of
protection.

The vermin trap 520m SSW of Trowlesworthy Warren House survives well, forms
part of the nationally important Trowlesworthy Warren and contains information
relating to the exploitation of rabbits in the Upper Plym valley. The
superimposition of this vermin trap upon earlier spoil dumps in a tin
streamwork, and the reuse of an earlier boundary wall provides stratigraphical
information relating to industrial and agricultural activity in this area.
This valley contains the densest concentration of vermin traps and other
structures associated with rabbit farming on the Moor.

Source: Historic England

Sources

Books and journals
Butler, J, Dartmoor Atlas of Antiquities, (1994)
Crossing, W, Crossing's Guide To Dartmoor, (1990), 431
Other
Devon County Sites and Monuments Register, SX56SE208, (1972)
Gerrard, G.A.M., The Early Cornish Tin Industry: An Arch. & Historical Survey, 1986, Unpubl. PhD thesis, St David's, Wales
MPP fieldwork by S. Gerrard, (1995)
PWDRO/72/1034, (1625)
Robertson, J G, The Archaeology of the Upper Plym, 1991, Unpub. Ph.D. Thesis (Edinburgh)

Source: Historic England