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[A similar version of this report was published in Caves & Karst Science, Vol.48, No.3, p.95-96. 2021. Transactions of the British Cave Research Association]

Abstract:

During 2011, a small-scale excavation in Toil and Trouble, located in the lower series of passages in Hallowe’en Rift, recovered a single animal bone from the fine sediments. The bone was later identified as Bison priscus 1^st phalanx. In April 2019, the bone was sent for radiocarbon dating, unfortunately, this was unsuccessful due to insufficient collagen in the sample. However, there is supporting evidence to suggest it is the find is of Pleistocene date and adds to the existing list of Mendip caves that have yielded ice age mammalian faunas.

Introduction

Hallowe’en Rift (Halloween Rift), NGR ST 5353 4809, altitude 130 metres(m) above Ordnance Datum (MCRA, accessed 2021), located in wooded hillside lying to the north-east of the Wookey Hole Cave ravine (Mendip Hills, Somerset). Excavation of the cave was commenced in 1982, but by the end of the 1980s interest at the site had waned. Then, in the early 1990s activity in the cave re-commenced and it was during these excavations that the dig on the east side of the entrance was started. Interest, once again, waned as the participants moved onto pastures new. In 2009, the current phase of activity began, and this phase of work concentrated on expanding the cave to the east-side of the entrance. The exploration and investigation of Hallowe’en Rift remains an ongoing project and several potential leads are being actively pursued.

Figure 1. Survey of the eastern passages in Hallowe’en Rift, drawn by Duncan Price (2018) with additional annotation by author.

The cave consists mostly of a low bedding, partially filled with sandy silt with cobbles and boulders of dolomitic conglomerate and frequent fragmented speleothems, including stalagmites, stalactites, and flowstone. The low bedding occasionally intersects rifts, that are, generally, northwest/southeast aligned.

Faunal remains

During 2011 an excavation in the lower series of passages known as Toil and Trouble, a single animal bone was recovered from the fine sediments. The bone was later identified as Bison priscus 1^st phalanx (Danielle Schreve, personal communication). In April 2019, the bone was sent for radiocarbon dating, unfortunately, this was unsuccessful due to insufficient collagen in the sample.

Bison priscus 1^st phalanx: peripheral view (top), ventral view (bottom). Scale = 5cm.

Table 1. Measurements of recovered Bison priscus bone.

The Steppe Bison (Bison priscus) existed in the British Isles, Europe and beyond from the Middle Pleistocene before becoming extinct at the end of the last Ice Age, about 10, 000 years ago (Marsolier-Kergoat et. al., 2015)

In the  British faunal record, mammal assemblages identified in caves are a valuable resource. Bison (Bison priscus) is recorded as part of the mammal fauna assigned to the Joint Mitnor Cave mammal assemblage-zone (MAZ), Marine Isotope Stage (MIS) 5e, c.128-116 ka and to the Bacon Hole MAZ, MIS 5a. However, a faunal grouping dominated by bison and reindeer, the Banwell Bone Cave MAZ, is believed to correlate closely with the Early Devensian, MIS 4, c.71-59 ka. Mendip sites containing a Banwell Bone Cave MAZ fauna includes the nearby cave site, Hyaena Den; and in the wider  environs at Picken’s Hole, Bleadon Quarry, Brean Down and Limekiln Hill Quarry. Also, to the north of the Mendip Hills at Pen Park Quarry in Bristol. The Banwell Bone Cave MAZ is a vertebrate assemblage from a cold climate (Currant and Jacobi. 2001). The mammal fauna of Banwell Bone Cave includes Lepus timidus, mountain hare; Vulpes lagopus, arctic fox; Vulpes Vulpes, red fox; Canis lupus, wolf; Ursus arctos, brown bear; Lutra sp., an otter; Gulo gulo, wolverine or glutton; Rangifer tarandus, reindeer and Bison priscus bison. Bison has also been recorded from the Lower Cave Earth deposits at Pin Hole, Creswell Crags, Derbyshire, and listed as part of the Pin Hole MAZ, Middle Devensian, MIS 3, c.59-24 ka. The Pin Hole MAZ also includes woolly mammoth (Mammathus primigenius), woolly rhinoceros (Coelodonta antiquitatis), wolf (Lupus lupus), as well as mountain hare, red-cheeked suslik, red fox, brown bear, stoat, polecat, spotted hyaena, lion, wild horse, giant deer, and reindeer. No evidence of bison was found in deposits attributable to the Gough’s Cave MAZ, MIS 2, c. 12.9-9.9 ka (Currant and Jacobi, 2001).

Comments

Speleothems from Hallowe’en Rift have been sampled and uranium-series dates obtained from the speleothems span MIS’s 15-13, 7c, 5e and 3,  with the youngest date 51.26 +0.31 −0.32 ka (Simmonds, 2019). Higham (2006) gives dates for Bison priscus bones recovered from Banwell Bone Cave as 52,700 ±1900 14C age BP to >59,000 14C age BP and for Hunters Lodge Inn Sink as >54,800 14C age BP. These dates fall within the range 59-24 ka, Middle Devensian, MIS 3. It is likely that the bone recovered from Hallowe’en Rift is contemporaneous with these dates. This Pleistocene date adds Hallowe’en Rift to the existing list of Mendip caves that have yielded ice age mammalian faunas.

Further excavation in this passage was abandoned due to the instability of the area. No other faunal remains have been recovered from the cave, so far. We are still looking.

Acknowledgements

In 2019 an application to fund radiocarbon dating was accepted by the British Cave Research Association (BCRA) Cave Science and Technology Research Fund (CSTRF). Unfortunately, the funding was not used due to a lack of collagen in the sample making it unsuitable for radiocarbon dating.

References

A Currant and R Jacobi. 2001. A formal mammalian biostratigraphy for the Late Pleistocene of Britain. Quaternary Science Reviews 20 (2001), Elsevier Science Ltd. 1707-1716

Marsolier-Kergoat, M-C., Palacio, P., Berthonaud, V., Maksud, F., Stafford, T., Bégouën, R., and Elalouf, J-M. 2015. Hunting the extinct Steppe Bison (Bison priscus) mitochondrial genome in the Trois-Frères Palaeolithic Painted Cave. PLoS one. 2015; 10(6); e0128267

MCRA (Mendip Cave Registry & Archive) www.mcra.org.uk/registry/sitedetails.php?id=150 Accessed 2^nd November 2021

Simmonds, V J. 2019. Evidence for Pleistocene frost and ice damage of speleothems in Hallowe’en Rift, Mendip Hills, Somerset, UK. Cave and Karst Science, Vol.46, No.2, (2019) 74-78

T F G Higham, R M Jacobi, and C Bronk Ramsey. 2006. AMS Radiocarbon Dating of Ancient Bone using Ultrafiltration. Radiocarbon, Vol 48, Nr 2, 2006, p179-195

All photographs by the author unless stated otherwise.