Bats
‘A few tips for attracting bats to the garden & farm yard’
Donna Mullen
Bat boxes
The best bat homes are in your attic or the attics of your outbuildings. It is here that females have their babies. Bat boxes are useful, but often house single bats or groups of males. The problem with most bat boxes sold in Ireland is that the entrance gap is too big – they are built for bigger British bats. The maximum size for the entrance hole should be 18mm, and ideally 15mm is perfect. Any larger and they wont be used by bats. It’s about the size of your thumb – if your thumb can wriggle around in the entrance hole, it is too big.
Bats don’t chew wiring or carry diseases, and they have only one young every year or two, so please welcome them into attics from May- Sept to have their babies.
Light Pollution
Bats need their eyes to see, and their eyes are used to working in darkness. Turn on a spotlight and they are dazzled. Bright lights create a physical barrier to bats and can stop them getting to their roosting places. In addition, moths are drawn to the lighting, and flap in circles until they are exhausted.
The dark spaces become like deserts, with all food sucked away by lighting, leaving the bats to starve. Some bats try to chase after insects at lighting. But they are at risk of being eaten by predators – now birds and cats can easily see them, and they no longer have the protection of the night.
So, turn off all outdoor lights! It is particularly important to keep lighting levels low with the use of bollard or ground lights – so people can see pathways and tracks, but the light does not spill up into the trees and sky. There should never be lighting on waterways. Waterways are the bat motorway system, with bats commuting, feeding, and drinking in these areas.
It is important to check if bats are using old buildings before putting lights on them. Small ‘fairy light’ type lights can be used to highlight a pretty feature of a building without floodlighting an entire building.
Tall hedgerows
Bats need tall hedgerows to commute. It is safer for them when flying high (they can keep away from cats etc) and hedges provide insects as food and shelter from the wind. So let your hedgerow become tall !
Areas of long grass
These provide much more insect diversity then areas of short grass. You don’t have to have a pristine wildflower meadow – almost any areas of long grass will attract insects.
Here is a podcast with Donna on ‘What do bats need to make a farm their home?’
About Donna Mullen
More information on Donna’s farm and a podcast can be listened to here. Ambassador since 2019
‘How to attract bat life to a farm’
Tommy Earley
About Tommy Earley
More information and a short film on Tommy’s farm here. Ambassador since 2019
