Study

An investigation of the impact of development projects on bat populations: comparing pre- and post-development bat faunas. Irish Bat Monitoring Programme

  • Published source details Aughney T (2008) An investigation of the impact of development projects on bat populations: comparing pre- and post-development bat faunas. Irish Bat Monitoring Programme. Bat Conservation Ireland report.

Actions

This study is summarised as evidence for the following.

Action Category

Change timing of building work

Action Link
Bat Conservation

Retain existing bat roosts and access points within developments

Action Link
Bat Conservation

Relocate access points to bat roosts within developments

Action Link
Bat Conservation

Provide bat boxes for roosting bats

Action Link
Bat Conservation
  1. Change timing of building work

    A before-and-after study in 2004–2008 of one building renovation in Ireland (Aughney 2008) found that carrying out roofing work outside of the maternity season, along with retaining existing bat access points, resulted in a similar number of brown long-eared bats Plecotus auritus using a roost within an attic before and after renovations. Fifteen brown long-eared bats were counted roosting in the attic space of the building before renovation work. After the renovation work, sixteen brown long-eared bats were recorded exiting the roost through the retained access points. The building was an 18th century Georgian house that had the roofing felt and roof slates replaced. Original access points to the roost within the attic of the building were retained by installing four vents in the ridge tiles. The renovations were completed outside of the maternity season (date not reported). The attic was surveyed once in 2004 before the renovations, and once with an emergence survey in September 2008 after the renovations.

  2. Retain existing bat roosts and access points within developments

    A before-and-after study in 2004–2008 of one building renovation in Ireland (Aughney 2008) found that retaining four existing bat access points, along with restricting the timing of roofing work, resulted in similar numbers of brown long-eared bats Plecotus auritus using a roost within an attic before and after renovations. Fifteen brown long-eared bats were counted roosting in the attic space of the building before the renovation work. After the renovation work, sixteen brown long-eared bats were recorded exiting the roost through the retained access points. The building was an 18th century Georgian house that had the roofing felt and roof slates replaced. Original access points to the roost within the attic of the building were retained by installing four vents in the ridge tiles. The renovations were completed outside of the maternity season (date not reported). The attic was surveyed once in 2004 before the renovations, and once with an emergence survey in September 2008 after the renovations.

  3. Relocate access points to bat roosts within developments

    A before-and-after study in 2004–2008 of one building renovation in Ireland (Aughney 2008) found that after relocating the access points to a bat roost within an attic during renovations, fewer brown long-eared bats Plecotus auritus used the roost and no bats were observed flying through the new access points. Before the renovations, 19 and eight brown long-eared bats were recorded exiting the roost through two original access points. After the renovations, no bats were observed exiting through two relocated access points and the number of droppings found inside the attic (<100) indicated that fewer bats were using the roost than before the renovations (number not reported). The building was a 19th century brick house. During renovation work, two bat access points consisting of angled slats (‘louvres’) were installed in the roof in different locations to the original bat access points. Renovations were completed in early 2007. Emergence counts were carried out once in June 2004 before the renovations, and once in August 2008 after the renovations. An internal inspection was carried out in October 2008.

  4. Provide bat boxes for roosting bats

    A study in 2004–2008 of five road developments and three residential and commercial developments in Ireland (Aughney 2008) found bats of four species occupying 33 of 150 bat boxes (22%) and bat droppings in 77 of 150 bat boxes (77%) across all eight sites. Overall, 91 individual bats were recorded occupying bat boxes, including soprano pipistrelles Pipistrellus pygmaeus (68), common pipistrelles Pipistrellus pipistrellus (17), Leisler’s bats Nyctalus leisleri (5) and Daubenton’s bat Myotis daubentonii (1). Bat droppings of Pipistrellus spp. were recorded in 62 bat boxes, Leisler’s bat droppings were recorded in 12 bat boxes and Myotis spp. droppings were recorded in three bat boxes. Bat boxes were either woodcrete (137 bat boxes; either Schwegler designs 1FD, 1FF, 1FN, 1FS, 2F, 2FN or 2F-DPF), wedge-shaped wooden bat boxes (5 boxes) or standard wooden bat boxes (8 boxes). At each of eight sites, 3–33 bat boxes were installed in 2002–2008 as mitigation for habitat loss. Each of the 150 bat boxes was checked once in June, October or November 2008.

Output references

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, terrestrial mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read latest volume: Volume 17

Go to the CE Journal

Subscribe to our newsletter

Please add your details if you are interested in receiving updates from the Conservation Evidence team about new papers, synopses and opportunities.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust