Updated SBG response to SCC Westdown Quarry expansion consultation – 30th June 2021

The group was not consulted by Somerset County Council on this application, details of which can be found on their website:

We had been invited to reply to Hanson consultation in December 2020, and our reply is published here: https://somersetbat.group/2020/12/04/response-westdown-quarry-expansion/ This text was also copied into our 29/6/21 comments

Our reply to SCC consultation as submitted on 29th June 2021 was as in black below. We submitted with updaged information of 30th June 2021, with the additions in blue below.


I am writing on behalf of the Somerset Bat group to raise concerns about this application. These are updated comments (in blue) and totally replace our comments previously submitted on 29/6/21.

The full text of these comments, and diagrams, are published on our website here: https://somersetbat.group/2021/06/29/scc-westdown-consultation/

Our previous response to Hanson’s pre application consultation (Dec 2020) also form part of our current comments, and are published here (and copied below): https://somersetbat.group/2020/12/04/response-westdown-quarry-expansion/

Overall Summary

  1. Lesser Horseshoe bats – We agree with Natural England’s comment (22/6/21) that “Further information is needed to determine the significance of impacts (on) lesser horseshoe bats and the scope for mitigation”.
  2. Greater Horseshoe bats – However we also state that further information is needed to determine the significance of impacts on greater horseshoe bats, the wider impacts on the Mells Valley Bat SAC, and the scope for mitigation.
  3. Mitigation, NOT restoration – We note that the technical guidance referred to is for the North Somerset and Mendip Bats SAC, this is not the updated “Technical Guidance Mendip District SAC Bats“, which includes a requirement for mitigation and enhancement, NOT just restoration. We agree with Natural England that the proposed mitigation measures are mostly “end game”, 25+ years time. In the intervening 25 years there are several “likely Significant Events (LSE)” identified in the HRA report that could lead to major declines, or extinctions, of the local horseshoe bat populations. These identified LSE must be mitigated, and bat habitat enhanced, BEFORE work commences.
  4. Old Quarry Faces – As we expected, bats were found to be roosting in cracks, crevices and fissures in the old quarry walls. We feel the impact of this habitat loss has been downplayed in the reports, and it is not clear how death of bats will be prevented during quarry operations, especially in Asham Void.

Impacts on lesser horseshoe bats (LHS)

We congratulate the surveyors on finding at least 3 new LHS roosts and confirming their linkages.

Westdown Farm is a significant maternity LHS roost, as quoted in the Apx 11B Bat Baseline “in August 2019, 70 lesser horseshoes were recorded traveling south-east away from Westdown Farm, 20 traveling north-west away from Westdown Farm (towards Asham Void), and four were recorded traveling south-west.”

The loss of Westdown farm will have a significant impact on the local LHS population, however the increasing noise and vibration will disturb bats roosting at Westdown Farm from very early on in these works, with potential for roost abandonment.

LHS Recommendations
  1. Full mitigation for the loss of Westdown farm be made before any works are commenced.
  2. Any mitigation roost construction has to be away from the disturbance areas, while allowing flight corridors to the other interlinked roosts.
  3. Any LHS mitigation roost provided is designed so as to exclude greater horseshoes.

Impacts on greater horseshoe bats (GHS)

The Ch11 Biodiversity report states that greater horseshoes are “predominantly within densely vegetated corridors within the Fordbury Water corridor” This is contradicted by the Apx.11b Bat Baseline report which states 40% of the GHS records were from other parts of the site. Hence these other areas cannot be easily dismissed as unimportant for GHS.

The previous larger GHS radio tracking study (Billington 2000 #403) found that Fordbury Water is used as foraging areas/flight routes. However he found GHS also used:

  • The hedges to Westdown Farm from Asham, and those around the farm, often on their commute south to forage in Cloford Quarry
  • The bottom of Asham Void as a foraging area/flight route
  • The woodland between Asham and Westdown, and the faces of old Westdown Quarry as a foraging /flight route.

This is shown in the extract from report Billingon #403 below

Figure1 - Extract from EN403(2000) - Asham bat foraging areas/flight routes in yellow. Approx foraging area within red shading. Point 2 is the Asham Stone Conveyor Tunnel roost.
Figure1 – Extract from EN403(2000) – Asham bat foraging areas/flight routes in yellow. Approx foraging area within red shading. Point 2 is the Asham Stone Conveyor Tunnel roost.
Radio tracking greater horseshoe bats

It is disappointing that only one GHS was successfully radio tracked. No species wide conclusion can be drawn from the behavior of one individual bat. GHS horseshoe females have individual territorial hunting patches, and other GHS will occur elsewhere than illustrated.

More information needs to be collected to establish the significance of the site for GHS foraging.

We also note there is an inconsistency in the summary of the GHS radio tracking across the various reports:

  • The HRA (table 4.1) report states “two females were tagged and radio tracked back to the same maternity roost at Wadbury House”
  • Whereas the Apx. 11B Bat Baseline table 3.9 report states:
  1. Female (pregnant) 31/05/2019 – Tagged at Asham Wood – Following release of the bat, it travelled very quickly north-east along the Fordbury Water corridor and signal was subsequently lost. The individual was not tracked to any roost sites and it’s signal was not regained during any other surveys carried out at the Site Survey Area
  2. Female (lactating) 22/07/2019 – Tagged at Fordbury Water Corridor – It was tracked back to a single roost site – Wadbury House

Assuming the more detailed Bat Baseline is correct, the assumption made in the HRA cannot be made. The pregnant female could have been roosting on site, or at other identified roosts in the NE direction, such as Dead Woman’s Bottom, Chantry Grotto or even Cherry Tree Farm Barn.

Stone Conveyor Tunnel

Initially the Somerset Bat Group (SBG) were pleased to be able to assist Hanson’s with advice on the long overdue grilling of the previous GHS maternity roost. However the quarry now prepares for commercial operation, SBG informed Hanson’s in Oct 2020 that ongoing it should be monitored by professional consultants, and that remedial works were required before safe access could be gained by them.

Unfortunately since the grilling was completed in 2019, the tunnel has been left unlocked, and has suffered vandalism, used for paintball practice, had fires set. Every time we have inspected (from the outside) there was fresh evidence of people gaining access to the roost, and potentially disturbing roosting bats.

It is therefore not surprising that low numbers of GHS are roosting at the site, and urgent steps need to be taken by Hanson’s to rectify this and protect the roost from ongoing disturbance, and unauthorised entry.

New hibernation Roost/connectivity

Bat group member and consultant Geoff Billington shared comments with group members regarding this. Geoff was employed by English Nature in 1999/2000 and undertook the only major GHS radio tracking over the site that we are aware of. His comments are:

“<70m from the proposed quarry is a greater horseshoe bat nursery site which in 2000 had about 40 adults, part of the Mells Bat SAC. This roost in the old Asham Stone Conveyor tunnel is linked to a larger roost at Wadbury, near Mells. Looking at the proposal plan it does affect the large part of the network of foraging areas and flight routes occurs across this area for this roost.

I got involved with a quarry proposal in South Devon several years ago, and there was great concern expressed about blasting much further away from roosts and in that case it was not a nursery roost.

It is my view as it stands an objection should be raised that full evaluation for greater horseshoe bats in/around the proposal is made and good proposals to include a new roost would have to be created further away from the new quarry (northwards) and new hedgerows created between the A361 and to the North East to mitigate for loss of key greater horseshoe areas which would still need to be subject to a HRA to determine if the effects are low enough to not impact on the SAC.”

Greater Horseshoe recommendations

  • More successful radio tracking of GHS is carried out to better understand their use of the site both for foraging and as a commuting route.
  • A new GHS mitigation roost to be established away from disturbance in the north of the site, before any works are commenced, and new connectivity hedges established
  • The Stone Conveyor Tunnel to be kept secure and regularly checked. Remedial works undertaken to allow safe access, then its use by bats monitored 3 times a year by professional consultants.

Mitigation Not restoration

The HRA (Table 3.2) report states ” The restoration plan is ultimately designed to create ecologically valuable habitats and will, in the long-term, provide an enhanced foraging resource for greater horseshoe bats. In the short term, however, there will be a loss of foraging and commuting resource until habitats mature. This is not acceptable.

Group Committee member Larry Burrows (former SCC Ecologist and author of above) stated that in the Technical Guidance Mendip District SAC Bats Mitigation should include replacement habitat at least to the value lost and now should include enhancement. This should not be a restoration scheme which won’t be until quarrying ceases.”

The Ch11 Biodiversity states (11.11.23) that “The effect on greater horseshoe bats, is not significant” however some of their supporting conclusions are incorrect. Such as GHS will not use a deep water aquatic habitat for foraging hence this should not be included in the mitigations for them.

Regardless of what mitigation measures are decided on, a Monitoring Strategy also needs to be included in order to ensure continued use of the site by SAC bats and includes measures to rectify
the situation if negative results occur.

Mitigation recommendations

  • New proposals are needed to address the short and medium term loss of bat habitats and provide enhancements, to align this proposal with Somerset County Council Guidance.

Old Quarry faces.

The Apx.11B Bat Baseline (3.1.2) report rightly acknowledges there are “hundreds of metres of exposed quarry face within the footprint of the Site Survey Area that may have the potential to support roosting bats … “

However it then says “no targeted survey effort has been applied to ascertain the presence of what are assumed to be (if present) other low or moderate conservation value … exposed quarry faces, such as roosts in use by single individuals or very small numbers of non-breeding bats … It is considered that such roosts are used by bats sporadically .. Such roost sites are not considered, in isolation, to contribute significantly to the conservation status of any of the species that use them”

We consider this an incorrect argument as:

  • There is no evidence of sporadic use. Cracks, fissures , crevices and small caves in the old quarry faces are suited to year round use, summer and hibernation.
  • There is no evidence of “small numbers”. There is up to a kilometer of cliff face, containing potentially many thousands of potential roost spaces. 9% of the bats recently radio tracked used the quarry faces to roost.
  • A single crevice lost will not impact the conservation status of a species, however the loss of many such roost spaces would be a major impact.

The report goes on to correctly state “the loss of any such roost sites …would certainly be
licensable if and when they needed to be removed”

Old Quarry faces recommendation

Greater emphasis be placed on the old quarry faces as potential bat roosts. A proper strategy be proposed to ensure all such roosts are found and licences applied for. Rather than rely on a ad-hoc “case by case” basis.

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