14-Sep-2021

Bowood Lane - more Bats

Surveys indicate substantial bat activity around Bowood Lane, and the presence of rare species.
The bats are threatened by planned works for HS2

Bat Survey report

A local resident writes -

From the 26th August through to the 2nd September, I carried out overnight bat surveys at the trees due for felling by HS2 at Bowood lane for bat activity. I had been asked to do so by a group of local residents who know that I have the equipment here to do so and because previous surveys had indicated a large number of bats in this area.

Using tamper-proof professional standard overnight detectors, I discovered a high amount of bat flight activity for just 5 trees and then, after an evening and sunrise study to track their flight paths, found they led to one of the trees in particular; so I thought that it may be a Potential Bat Roost (PBR). 

Also, I carried out a dawn survey on Monday 30th August with my husband, from 3.30 am until sunrise at 6.10am.

That morning we gathered observational  and recorded evidence that backs up my belief that this could be a potential roost; pipistrelle bats returning to the tree and circling around it just before sunrise and then disappearing. 

The data recorded over the 6 nights that I monitored Bowood lane is currently with Bioscan - a professional ecology company - for accurate analysis. It was gathered using an Anabat Express Pro detector which has an omni-directional microphone, an integrated gps system and records up to 250khz.

We also recorded on a separate  echometer - at 32 khz - what appears to be barbastelle bat calls by  these trees. They are identifiable by a kind of clacking sound at this frequency (like a castanet). Although the video recording of the echometer is poor quality, the fact remains that you can clearly hear the bat calls and see the frequency at which they are being transmitted. An ecologist has studied this video footage and agreed it is barbastelle bat calls that can be heard.

Having gathered strong evidence of large bat activity and the presence of a PBR, on the morning of the Bowood road closure, August 31st, I was so concerned that the EKFB/HS2 ecologist would not carry out full climbing surveys on these trees before felling them, that I arrived at Bowood lane at 7am and stayed until 10.30am in order to chat with him.
When the ecologist arrived, he was extremely polite and helpful and willing to engage with me. He told me that he was actually there that day to oversee the clearance of hedgerow only BUT he looked at the trees in question with me and assured me that these trees have been 'flagged up as potential bat roosts with features' and that, as such, they would definitely have full climbing surveys carried out on them. This conversation was witnessed by another resident but when I questioned which trees of the 5 he meant, he couldn't say off the top of his head. 

This has led me to believe that ecological surveys MUST have been carried out by EKFB on those trees in order for him to give such a definite response that they had been identified as PBRs.
But when were these surveys done? How recently?
And, as he was unable to identify which of the trees the EKFB ecologist had said were PBRs, I am concerned that the trees I have identified as such may be overlooked. 
I can assure you that no ecological surveys have been carried out by EKFB on any of these 5 trees in Bowood lane the week before the road closure and, with my new study and data evidence to hand of potential bat roost and barbastelle bats, I contacted Jane MacBean at Buckinghamshire Council and Thames Valley Police  to intervene urgently and insist that EKFB suspend felling of these trees until full climbing surveys were carried out by HS2 ecologists, with reports of their findings shared with BC.

With regards the potential of barbastelle bats being present in Bowood lane at these trees, they need to obtain guarantees from EKFB ecologists  that a careful survey of the Ivy covering all the tree trunks is carried out too. Barbastelle roost in exactly these types of trunks and change their roosts frequently. Although usually their day roosts would be found in more dense woodland areas, it is not impossible that they may roost in a familiar habitat (especially as there has been so much fragmentation of their usual flight paths to habitats and destruction of trees nearby). In any event, the mere fact that we have recorded (what strongly suggests) the rare barbastelle bat call under these trees, means that EKFB ecologists should be surveying for this.  

There is one tree that we strongly feel could be the pipistrelle roost - but a tree next to it needs inspecting closely too, as it is so difficult to discern which tree the bats disappeared into at sunrise - they move so fast. I have taken what3word locations for each of these trees and shared such with BC, EKFB and Thames valley Police (TVP).

All of the above information with regards the bat data collection and presence of a PBR and potentially barbastelle bats  was also shared on August 31st by Jane Macbean with Kim Birtwhistle from EKFB.

I continued to monitor the trees at Bowood overnight until 2nd September and have carried out a FOI request for the HS2 bat surveys that presumably must have been conducted before the road closure on August 31st.

I have since discovered that Bowood Lane has not been registered with Natural England as a site  by HS2 and there is therefore no licence in place that protects any PBRs that may be present in those trees.

All of the above concerns (including the fact that Bowood Lane is not a registered site with NE) have been shared with TVP - PC Christopher Vaughan and PC Matt Holland, who routinely deal with potential wildlife crimes, have dealt with the case very thoroughly. They attended the site, spoke to the site team there and requested information regarding the planned date of the bat survey of those trees by an ecologist. They have informed EKFB that they wish to attend that survey themselves if possible, in order to ensure that full and thorough climbing surveys are carried out and to put concerned residents minds at rest.

They have written in detail to me to say that they have informed EKFB of their intention and I will be continuing to communicate with the TVP to ensure that this is indeed what happens when the time comes.     

Birds

Two other issues arising with the trees at Bowood are: local residents also asked me to raise the question with EKFB ecologists about the yellow hammer nest that was discovered previously. Apparently work at Bowood was suspended because of its acknowledged existence. So, they have asked: what has happened to that nest? When did ecologists last check it? I did ask this question but to date have received no reply.

Finally, during my dawn bat survey, I also observed a woodpecker entering the nesting box that has been attached to the last of the 5 trees (the most Westerly). I told the site ecologist this too and he said he would pass this information on to EKFB. I also passed the what3word location and this woodpecker information on to Jane MacBean at BC.

I hope that ecologists will check carefully for a woodpecker or yellow-hammer nest too when they carry out their pre-felling surveys, as TVP have confirmed recently with me that a bird’s nest was overlooked by ecologists carrying out pre-felling surveys in Leather Lane. (This is currently still under investigation).  

In conclusion

The data and bat flight recordings from Bowood lane Aug 26th to Sep 2nd 2021 is currently being analysed professionally and the report will be shared with relevant interested parties. However, the indications very strongly suggest that at least one of the trees is a PBR and that there are barbastelle bats using the trees in Bowood Lane at the very least as a flight corridor but potentially as a day roost.
Therefore it is essential full climbing surveys and careful study of the ivy covering these trees is carried out by HS2 ecologists before they are felled (especially now that the colder months are coming and the bats may start hibernation in the next few weeks ).  

I am continuing to collect and record Overnight Data occasionally at Bowood and observational studies are still being carried out and recorded at the PBR in Bowood Lane by local residents. This will continue until the end of the bat season.

I will also be using an infra-red video camera next week at a second dawn survey. I will share this with interested parties if there are any recordings of note.

TVP have expressed their intention to ensure thorough ecology surveys are carried out on those trees pre-felling.  

The FOI request regarding previous bat surveys by HS2 has not been returned yet but when (and if) received, it will be shared with relevant interested parties.

Jane MacBean from BC has challenged EKFB via Kim Birtwhistle with regards the lack of site registration at Bowood. The response received stated that current work at  Bowood does not include the felling of these trees and that the correct procedures will be adhered to when the time comes.
However, I am pretty confident that the correct procedures will be followed now. 

 

Licenses ?

Several FOI requests have been submitted regarding Bowood Lane, from which it would appear that

The absence of a license should prevent EKFB from disturbing any bats in the vicinity, and in particular, from felling the trees.

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