Remote badger monitoring saves money for Network Rail
Badger setts are a regular feature of our railway embankments. Upgrading and maintenance works are often the subject of licence applications to Natural England to disturb or even exclude the badgers to protect them from engineering works and ensure that legislation is complied with.
This site at Sundon Loop, Bedfordshire included a badger sett on a railway line that appeared to be used infrequently. The requirements of Natural England are to establish the current type of badger sett and level of usage. This work is generally undertaken by repeated visits to the site and can include soft stuffing the sett entrances with twigs or leaves, leaving sand outside of entrances to capture footprints and bait marking using coloured pellets to look at territory size.
If a licence is required for works adjoining or causing disturbance to a badger sett, then a period of six weeks is required to submit and request a licence and then a minimum of three weeks to do the work, which must be supervised.
This is a lengthy and costly process, and presents challenges when scheduling engineering works on a busy rail network.
A consultant inspected the site and it was confirmed that at least one of the holes identified had the potential to be a badger sett. The sett looked like it had recently been dug, as fresh spoil was recorded outside the entrance.
As the sett was only small (potentially only one hole) the likelihood was that it was an outlier sett and not a main breeding sett. Following an initial consultation with Natural England, we proposed using night cameras with heat sensitive triggers to monitor the sett for a period of 21 days to see how often the sett was being used. We used two cameras to monitor both this hole and an adjacent hole that had some limited potential.
Our survey showed that the hole was regularly being used by foxes and rats. On day three, the camera recorded a badger entering the hole for a three hour period, after which only foxes were recorded using the hole.
Natural England agreed that, if the hole was not used for a period of 21 days, then the sett could be closed. Cameras were left on the sett and subsequently re-checked. Throughout the project, additional species recorded with the cameras included fox, muntjac deer, rats, tawny owl, ferret-polecat and rabbit.
As our cameras showed that the sett was not used by badgers for a period of 24 days, it was closed using steel one-way badger gates. To comply with best practice, these one-way gates were placed on all sett entrances and left for a period of 21 days. Cameras were placed to assess the sett during the closure and ensure that no animals breached the gates.
The camera was left on site during the blocking of the sett so that any specific activity could be monitored. Leaving the camera on site ensured that no badgers were still inside the sett after the gates were put in place and, ultimately, the camera recorded no images of badgers attempting to access the sett.
This remote video recording technique has been cited as best practice by Network Rail, as we delivered significant savings for this project. Although this methodology cannot be applied to all situations, it allows the assessment of badger setts in a timely and cost effective manner and gives detailed information on the type of badger sett and how it is being used. The detailed information we record can also be used to inform a licence should one be necessary.
“The use of this technique has saved us a significant sum of money which could be replicated at many sites. Baker Consultants’ experience of remote survey, and negotiation with the regulatory authorities got a speedy result allowing us to get on site faster and complete the works. “