Bats in Ireland
Bats are one of the most diverse groups of mammals on the planet. There are over 1,400 species currently known and they are found all over the world, with the exception of the Arctic, Antarctic and a few Oceanic islands.
Bats are an extremely diverse group with a wide range of feeding habits, including species which specialise in eating insects, fruit, fish, blood, nectar and even frogs. Some bats use echolocation to find food while others use their strong sense of smell and also sight.
Even though the largest diversity of bats is found in warmer, equatorial regions, we still have several species here in Ireland. All of Ireland’s bats are insectivores, meaning they specialise only in eating insects. They also all use echolocation to hunt for insects. Each species prefers a different habitat, such as near rivers, woodlands or grasslands.
There are nine confirmed bat species in Ireland, belonging to two separate groups:
- Family Rhinolophidae
- Lesser horseshoe bat (Rhinolophus hipposideros)
- Family Vespertilionidae
- Common pipistrelle (Pipistrellus pipistrellus)
- Soprano pipistrelle (Pipistrellus pygmaeus)
- Nathusius’ pipistrelle (Pipistrellus nathusii)
- Leisler’s bat (Nyctalus leisleri)
- Brown long-eared bat (Plecotus auritus)
- Daubenton’s bat (Myotis daubentonii)
- Whiskered bat (Myotis mystacinus)
- Natterer’s bat (Myotis nattereri)
Several of these species, like the common and soprano pipistrelles, are common and widespread. Others, such as the lesser horseshoe bat, are rare and restricted in their distribution. There are also several species with unconfirmed records in Ireland, or species which may be vagrants here, including the Brandt’s Bat (Myotis brandtii), Greater Horseshoe Bat (Rhinopholus ferrumequinum), Noctule bats (Nycatlus noctula) and Barbastelle bats (Barbastella barbastellus) (Source: Bat Conservation Ireland).
Soprano Pipistrelle Pipistrellus pygmaeus (ialtóg shopránach)
The Soprano Pipistrelle is Ireland’s smallest bat. It is also one of the most widespread and common bats in Ireland. It is physically very similar to the common pipistrelle, reaching less than 6g weight, about the same as a 1 euro coin.
These bats can be found near woodlands and gardens, especially when these are close to water. They are insectivores and can eat up to 3,000 insects in one night. This includes moths, small flies and midges which are often caught and eaten while in flight. This species can be found roosting in the roof of buildings, but can also be found in tree holes.
The soprano pipistrelle was only identified to be a separate species from the common pipistrelle in 1999. While they are very similar physically, the soprano pipistrelle echolocates at a higher frequency of 55kHz while the common pipistrelle reaches 46kHz.
Leisler’s Bat Nyctalus leisleri (ialtóg Leisler)
In contrast to the tiny soprano pipistrelle, the Leisler’s bat (sometimes called the Lesser Noctule bat) is Ireland’s biggest bat. This bat can be easily identified as their hairs are uniquely coloured – the hair is darker at the base and much lighter at the tip. This bat is also unique as it tends to fly much higher than other species, and will dive down to catch beetles, dungflies, moths or craneflies. For this reason, it will often be seen flying high above open grasslands such as parks and fields, but can also be seen around streetlights and bodies of water. It is usually one of the first bat species to emerge in the evening, sometimes being mistaken for birds as they may emerge before sunset.
This bat is considered to be rare in Britain and the rest of Europe but is relatively common and widespread throughout Ireland, making the Irish population a stronghold of this species. There is also high genetic diversity amongst the Irish population of Leisler’s bats, adding to the global importance of this species in Ireland. It is also often found in roofing but can sometimes be found roosting in trees. In continental Europe, this species will migrate long distances, but they have not been recorded migrating in Ireland.
Daubenton’s Bat Myotis daubentonii (ialtóg uisce)
The Irish name for this bat literally translates to ‘water bat’, as this species can be easily recognised by its low level flight directly above the surface of lakes, rivers and canals. The Daubenton’s bat feeds on aquatic invertebrates, such as mayflies and caddisflies. It can even use its tail and feet to scoop up insects from the water surface and can swim if it accidentally ends up in the water. While there are other Irish bats that feed in close proximity to water, this behaviour is most commonly associated with the Daubenton’s bat.
The Daubenton’s bat can live for up to 22 years in the wild, but the average lifespan is probably about 4-5 years. They weigh about 15g and have a wingspan of 25cm. This species can be found roosting under bridges, in caves or in ruins and trees near water. They prefer to hibernate underground in caves, tunnels and mines. The Daubenton bat’s name comes from the 18th century naturalist Louis-Jean-Marie Daubenton.
Brown Long-Eared Bat Plecotus auritus (ialtóg fhad-chluasach)
This bat is distinctive due to its large ears, which are almost as long as its body. When resting, these amazing ears can be curled up or tucked under their wings. This species is quite common across the country. However, the Brown Long-Eared bat is rarely seen as it tends to forage in dense vegetation in woodlands and hedgerows, as it picks insects off of leaves. This can include spiders, beetles, caterpillars or moths. This bat can sometimes leave piles of moth wings and other insect remains underneath their perch.
This bat roosts in attics and roofing of buildings and also tree holes. It has a particularly low frequency echolocation of 25-50kHz, which can make them hard to detect with bat detectors. Some bats have been recorded to be up to 20 years old, but the average lifespan is probably closer to 5 years.
Lesser Horseshoe Bat Rhinolophus hipposideros (crú-ialtóg bheag)
The only member of the Rhinolophidae family in Ireland, the lesser horseshoe bat has a very restricted range in Ireland. It is thought to only be found in six counties – Cork, Kerry, Limerick, Clare, Galway and Mayo. This may be due to the reduced risk of frost along the western Atlantic coast. However, this species may have had a wider distribution historically, as bones from this species have been found in Waterford. Ireland’s population of this species is of international importance as it has seen a dramatic decline globally, and has become locally extinct in some parts of Europe.
This is Ireland’s only native bat species to hang upside-down with its wings wrapped around its body. It is easily identified by the horseshoe-shaped flap of skin around the nostrils. This species roots mainly in old buildings and hibernates underground in caves, mines and cellars. Its distribution is closely linked to deciduous woodlands as it usually forages in dense vegetation such as woodlands and scrub, especially when these are near water sources.
The Vincent Wildlife Trust has set up several bat reserves around Ireland specifically for the protection of lesser horseshoe bats. Due to the importance of this species, a Species Action Plan (SAP) for Lesser Horseshoe Bats was released by the National Parks and Wildlife Service and Vincent Wildlife Trust recently for 2022-2026. This can be found here.
Celtic Folklore
Bats had various meanings in Celtic folklore. In Scotland, bats were associated with the arrival of the ‘witching hour’ or the time at which witches have power over humans. In contrast, in the Isle of Man, bats’ arrival at sunset was considered a sign of good weather to come.
In Ireland, the Púca, as mischievous fairy, is thought to sometimes take the shape of a bat when taking humans on a nighttime adventure. In Welsh and Manx folklore, a creature known as a Cyhiraeth, similar to Ireland’s Banshee (Bean Sídhe), would flap her bat wings against windows at night to warn of an upcoming death in the house.
In Ireland, it is still sometimes said that a bat entering a house is a sign of bad fortune and that if a bat gets caught in a woman’s hair she will be destined for eternal damnation. In modern times, bats have become a common symbol for Halloween, which is descended from the Celtic festival of Samhain. In Irish, bats are sometimes called “bás dorcha” (dark death) or “sciathán leathair” (leather wing) although they are most commonly called ialtóg.
Ireland’s bats are all protected under the Wildlife Act (1976) and the Wildlife (Amendment) Act 2000. Bat’s are also a European protected species under Annex IV of the European Habitats Directive. It is an offence to intentionally harm a bat or disturb its resting place.
If you have found a grounded bat during the day, never handle it with bare hands as it may bite. Try to ensure it is in a safe, warm place and provide food such as mealworms or chopped up cat and dog food. You can also provide water in a small, shallow dish. Once the bat is safe, you can get further advice from Bat Conservation Ireland or Irish Wildlife Matters or contact the National Parks and Wildlife Service in the Republic of Ireland on (01) 888 2000.
Further Information
Bat Conservation Ireland https://www.batconservationireland.org/irish-bats
Bat Conservation Trust UK https://www.bats.org.uk/
Finch, D., Schofield, H., Floate, K.D., Kubasiewicz, L.M. and Mathews, F. (2020), Implications of Endectocide Residues on the Survival of Aphodiine Dung Beetles: A Meta-Analysis. Environ Toxicol Chem, 39: 863-872. https://doi.org/10.1002/etc.4671
Kotowska D, Zegarek M, Osojca G, Satory A, Pärt T, Żmihorski M. Spatial patterns of bat diversity overlap with woodpecker abundance. PeerJ. 2020 Jun 18;8:e9385. doi: 10.7717/peerj.9385. PMID: 32596056; PMCID: PMC7306217.
NPWS & VWT (2022) Lesser Horseshoe Bat Species Action Plan 2022- 2026. National Parks and Wildlife Service, Department of Housing, Local Government and Heritage, Ireland.
Written by Rebecca O’Sullivan
Rebecca O’Sullivan
Zoologist
