Introduction

Project description
A new 'bat tower' was constructed at Dalegarth Station, Eskdale Valley, Cumbria. This replaced an old station building, which was in a poor condition and obsolete. The old station building was scheduled for demolition to make space for the creation of a disabled access ramp to the platform.
Ecologist’s name and contact details
Victoria Burrows (ERAP Ltd)
Planning authority
Lake District National Park
Brief site description
Former station building in car park. Predominant surrounding landscape is montane, pasture, river and woodland.

Pre-works roost structure

Type of structure
Building
Use
Commercial Unit
Condition
Not In Use
Approx. age
Over 10 years old.
Main construction material of walls
Brick
Roof design
Pitched Roof
Roof material
Bitumen
Internal roof structure
Timber Frame

Pre-works roost description

Species
Common pipistrelle
Number of bats max count
47
Type of roost
Maternity Roost
Evidence of bats
Bats Recorded Emerging/Re-entering
Roost location
Eaves
Aspect of roost
SW
Height of roost entrance (m)
4
Roost material(s)
  • Timber
Nearest commuting feature
Hedge
Distance to nearest commuting feature (m)
Not reported
Photos or annotated figures of roost

Proposed works

Description of works
Removal of bat roost in original station building to facilitate demolition, followed by compensation in a new 'bat tower'. The old station building was removed in winter (when bats were absent), the roost area was carefully removed under the presence of a licensed surveyor.
Type of impact upon the roost
Long-Term Roost Modification and Roost Loss

Proposed mitigations

Type of mitigation
Compensation
Specific technical detail of measure
Bat House: The objective was to replicate the roost position, access and conditions of the existing roost by providing a purpose built bat tower. This would also provide a feature to promote bat conservation to the tourists attending the Ravenglass to Eskdale Railway. Bat access to the purpose built tower is in exactly the same position at the roost access at the old station building. The station building roost was above the kitchen. A low voltage heater has been installed at the bat tower to replicate the warm conditions above the kitchen. Similar materials have been used although the timber was new. Size: The tower is 1500mm by 1500mm by 4640mm high Materials: Timber frame with hipped slate roof and hanging slates. Additional info: A purpose built "bat house" was built in exactly the same position. The roost access was in exactly the same position (this was recorded prior to demolition). Other provisions for use by roosting bats were also incorporated into the "bat house". In the interior, plywood baffles of differing lengths were inserted to provide roosting places for bats. Low voltage heaters were placed inside and the temperature and humidity will be monitored and altered as necessary (thermostat installed). This was built specifically to tie in with the new station building as there were very strict aesthetic regulations and the use of materials was specified by the Lake District National Park Authority. A hatch was installed for inspection purposes.
Roost location
Bat House
Aspect of roost
S
Height of roost entrance (m)
4.4
Roost material(s)
  • Clay Hanging Tiles
  • Slate Tiles
  • Timber Roof Frame
Nearest commuting feature
Hedge
Distance to nearest commuting feature (m)
Not reported
Photos or annotated figures of roost

Actual mitigations implemented

Type of mitigation
Compensation
Specific technical detail of measure
Bat House: The objective was to replicate the roost position, access and conditions of the existing roost by providing a purpose built bat tower. This would also provide a feature to promote bat conservation to the tourists attending the Ravenglass to Eskdale Railway. Bat access to the purpose built tower is in exactly the same position at the roost access at the old station building. The station building roost was above the kitchen. A low voltage heater has been installed at the bat tower to replicate the warm conditions above the kitchen. Similar materials have been used although the timber was new. Size: The tower is 1500mm by 1500mm by 4640mm high Materials: Timber frame with hipped slate roof and hanging slates. Additional info: A purpose built "bat house" was built in exactly the same position. The roost access was in exactly the same position (this was recorded prior to demolition). Other provisions for use by roosting bats were also incorporated into the "bat house". In the interior, plywood baffles of differing lengths were inserted to provide roosting places for bats. Low voltage heaters were placed inside and the temperature and humidity will be monitored and altered as necessary (thermostat installed). This was built specifically to tie in with the new station building as there were very strict aesthetic regulations and the use of materials was specified by the Lake District National Park Authority. A hatch was installed for inspection purposes.
Roost location
Other
Aspect of roost
N
Height of roost entrance (m)
4.4
Roost material(s)
  • Clay Hanging Tiles
  • Slate Tiles
  • Timber Roof Frame
Nearest commuting feature
Hedge
Distance to nearest commuting feature (m)
Not reported
Photos or annotated figures of roost

Monitoring data

Length of monitoring proposed
At least 4 years
Frequency of monitoring
Not reported.
Type of monitoring
Roost Inspection
Date and time
1st May 2008
Evidence recorded
One Pipistrelle bat was observed roositng beneath the barge board at thea eaves of the tower. Bat droppings were present on the sills and slates around the tower.
Internal temperature and humidity recorded
25 degrees
Interventions made
None reported.
Type of monitoring
Roost Inspection
Date and time
1st February 2011
Evidence recorded
Internal inspection confirmed 1000's of droppings inside the tower indicating bats had been roosting between the timber baffles. A few dead baby and juvenile bats indicated evidence of use by a maternity roost. Droppings were cleared away.
Internal temperature and humidity recorded
25 degrees
Interventions made
None reported.
Type of monitoring
Roost Inspection
Date and time
3rd October 2011
Evidence recorded
Similar results 1000's droppings present and a few dead baby bats. Droppings were cleared away. The next inspection is scheduled for October 2012.
Internal temperature and humidity recorded
25 degrees
Interventions made
None reported

Final details

Lessons learned
Heating a mitigation roost may have its advantages (it has been valuable in this instance). Creation of the roost access in exactly the same place as the previous roost seems to have contributed to the success