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Working with bats on the Isles of Scilly

bats isle of scilly

In the fifth article of the mini-series, Darren Mason (Head Ranger, Isles of Scilly Wildlife Trust) focuses on bats…

Bats were once common in Scilly but by the 1990’s they seem almost to have disappeared. This is undoubtedly down to habitat loss: improvements to barns and buildings, which they would have roosted in; and food availability: limited by the use of insecticides on farms. Due to changes in these practices, bats numbers now appear to be recovering.

So why are bats important?
Did you know that bats hunt insects including mosquitoes and flies to satisfy their considerable nutritional requirements? In order to survive, a bat must eat a third to a quarter of its body weight per night, which can be 3,000 insects. This is very important information if you are one of those people that mosquitoes like to feast on.

Cottage on Samson. Credit © BareFoot Photographer & IOS Wildlife Trust

What have bats got to do with the Isles of Scilly Wildlife Trust?
At the beginning of 2018, the Trust was informed that the Islands resident volunteer Bat Wardens would be stepping down from this role after 11 years at the helm. This left a worrying gap in the provision of bat conservation in Scilly so we set about finding a viable solution, which the Isles of Scilly Wildlife Trust could employ.

Bat conservation is a complex business. With bat groups, bat consultants, volunteers and paid professionals, Natural England and the Bat Conservation Trust, and then the “Scilly-factor” of a remote community of five inhabited islands, it was quite tricky to come up with a workable plan.

Two staff members (Darren H & Darren M) stepped up to the challenge and have now undertaken professional bat license training with Dr Sandie Sowler. Sandie has been involved in bat research and conservation since 1969 and has 24 years experience as an ecological consultant in the UK, focussing on bat conservation, EcIA’s and latterly, developing training courses; she has the full range of bat licenses with both Natural England and Natural Resources Wales, and has developed and delivered Bat Conservation Trust training courses since 2003.

Sandie kindly came to Scilly in June 2018 to train our staff, as the cost of sending our team away to the mainland for the course, would have been prohibitive. We are eternally grateful for Sandie’s enthusiasm and commitment to bat conservation in Scilly and for her help in finding a solution for Scilly that worked.

The Trust is now offering an ecological consultancy service for those needing information about the presence of bats or the possibilities of providing roost sites for bats within the local planning system. Homeowners/developers are often required by the Local Planning Authority to take into account bats when applying for planning permission; the Isles of Scilly Wildlife Trust will now be able to provide this service on a not-for-profit basis. We hope that this will enable developers/homeowners to do all they can to help our bat populations thrive.

Example of sonogram recorded and analysed during recent bat survey: common Pipistrelle. Credit: © IOS Wildlife Trust

What we currently know about bats in Scilly
In Scilly, seven species of bat have been recorded. However only three are resident; Common pipistrelle (Pipistrellus pipistrellus), soprano pipistrelle (Pipistrellus pygmaeus) and brown long-eared bat (Plecotus auritus). Other species recorded, such as Nathusius pipistrelle (Pipistrellus nathusii) which is migratory could also be resident.

Since the inception of our consultancy service in June 2018, Darren H & Darren M have had to analyse several sonograms which, though not definitive, have indicated a further two Myotis sp. (M.daubentonii and M.mystacinus) and very blurry photographs of what was thought to be Leisler’s bat (Nyctalus leisleri).

Whether these species have been blown off course during migration (in Europe Leisler’s is categorised as a long-distance migrant, whilst Daubenton’s and whiskered bats are classed as regional migrants), hitched a lift on a boat or have purposively migrated to the islands remains to be seen, but it makes evening bat transects and monitoring an exciting event.

In conjunction with this, the Isles of Scilly holds the UK’s southern-most population of common pipistrelle and two Biodiversity Action Plan (BAP) priority species. However, we do not currently have sufficient data to know much more and so an additional purpose of the Trust’s new venture in bat consultancy is to gain more data on where bats are roosting, be that maternity, hibernation or transition roosts, or if some species purposely migrate to islands.

Ultimately, we hope that increased information about bats and their whereabouts and requirements in Scilly will enable the Trust to create more suitable bat habitat so that they can thrive as an integral part of the islands ecosystem.

If you like what you’re reading then why not follow us on Facebook, Twitter or Instagram to get regular, daily instalments regarding our ongoing conservation in our remote south-west corner of the UK? With regular updates regarding all aspects of our work from land management to bat consultancy, education to seabird surveys, no day is ever the same and life is never dull!

Header Image: Common pipistrelle. Credit: © BareFoot Photographer & IOS Wildlife Trust.

Article written by: Darren Mason (Head Ranger, Isles of Scilly Wildlife Trust).