Geoffroy's bat
Myotis emarginatus
alin244 · Provincia di Pisa
Key facts in one look
- Diet
- Insectivore: spiders, flies
- Status in Georgia
- Native; a cave bat
- Size
- Body 4.4–5.5 cm, weight 5–10 g
- Habitat
- Caves, attics; broadleaf forest
- Family
- Vespertilionidae
- Conservation
- LC / LC
Geoffroy's bat (Myotis emarginatus) owes its Georgian name, "three-coloured myotis", to its fur: each hair is dark at the base, whitish in the middle and brick-red at the tip. The outer edge of its ear has an almost right-angled notch. Unlike many other bats, it is especially fond of spiders, which it picks off leaves and webs. In Georgia it is among the bats most closely tied to caves, and in some years it joins the large mixed colony of Ghliana Cave. If a bat flies into your home, do not catch it with bare hands: open a window and give it time to leave.
Identification
Geoffroy's bat: how to identify it
A medium-sized myotis with long, dense, woolly, reddish-brown fur. The belly is a pale yellowish-brown and does not stand out sharply from the back. The face is light brown, the ears brown, with a clear notch on the ear's edge.
It is medium-sized: it weighs 5–10 g, its body is 4.4–5.5 cm, its forearm 38–44 mm and its wingspan about 22–25 cm. The wings are brown and broad.
The ear is the main feature. Its outer edge has an almost right-angled notch, and its surface carries wart-like bumps. The tip of the tragus, the small fold inside the ear, does not reach the notch.
The fur is three-coloured: dark at the base, whitish in the middle and brick-red or reddish-brown at the tip. Natterer's bat is also medium-sized with long ears, but its back is greyish-brown and its belly white. Do not catch a bat to identify it: that is a job for specialists.
Colour
The back ranges from rust-brown to fox-red, and the belly is a pale yellowish-brown. The fur is long, dense and tousled. Young bats are almost entirely grey.
Swatches are illustrative. Do not identify a species by colour alone.
Often confused with
Geoffroy's bat favours broadleaf forest, wooded valleys and also dry open country. It spends the day in caves, rock-cut caves and the attics of large buildings, often together with horseshoe bats. In Georgia it is considered a cave bat and is one of the species most often found in underground sites. It has been found near Nokalakevi and Chakvistavi, in the Pskhu-Gumista reserve, in the Borjomi gorge, near Tskhinvali, near Mtskheta and in the Saguramo reserve. In the east it also lives in the Natlismtsemeli and David Gareja cave complexes. These are individual records, not a sign that it is common everywhere in these places.
The Geoffroy's bat map combines public iNaturalist observations. Regions are taken from the records-by-region table, and the status column separates regions with enough records from regions with too few records. Record counts reflect observation effort rather than population density. Records are still too few: no region has enough records yet.
Data: Reptiles.ge + iNaturalist · Methodology
- Field observation
- Several records in one spot
- Photo record
- Region with records
The main food of Geoffroy's bat is spiders and flies. Rather than catching prey in flight, it often picks it off leaves and other surfaces, and takes spiders straight from their webs. In Belgium it eats mostly blood-feeding flies, which are plentiful in cattle sheds. In the Spanish Basque Country one orb-web spider made up 80% of its food in August. It hunts low, in dense vegetation, and avoids open space.
Geoffroy's bat is sedentary: its winter and summer roosts are usually less than 40 km apart, though a movement of 105 km has been recorded. It hibernates in underground sites, and males often winter alone. It leaves to hunt in deep dusk. Mating takes place in the winter roosts. In early summer females gather in nursery colonies of about 200 animals on average, while males live apart. Each female has a single young, which she nurses for about a month. It lives up to 15 years. In Georgia it joins, in some years, the mixed nursery colony of Ghliana Cave, where 4,000–8,000 bats gather.
Globally Geoffroy's bat is rated Least Concern (LC, 2016), with a stable population. In Georgia, too, the 2021 national assessment rates it Least Concern (LC), with a stable population. In Europe it is threatened by habitat fragmentation, intensive farming and disturbance in caves. Killing flies in cattle sheds also reduces its food. In Georgia, Ghliana Cave, where it breeds in some years, has been assessed as the most threatened of the underground roosts: it suffers from disturbance, damage and light pollution.
Related guides
Continue with related pages
In both the west and the east. It has been found near Nokalakevi and Chakvistavi, in the Pskhu-Gumista reserve, in the Borjomi gorge, near Mtskheta and Saguramo, and in the Natlismtsemeli and David Gareja cave complexes. It is a cave bat and one of the species most often found in Georgia's underground sites.
Every hair on its back has three colours. The base is dark, the middle whitish and the tip brick-red or reddish-brown. From a distance its back therefore looks rusty or fox-red. Its English name "notch-eared bat" refers to the notch on the edge of its ear.
It will not attack you, but do not touch it with bare hands. A bat bite can be tiny and easy to miss. Rabies cannot be ruled out by appearance, although most bats people see are not rabid. After a bite or scratch, wash the spot with soap and water for at least 15 minutes and see a doctor; in an emergency, call 112.
Stay calm and take children and pets out of the room. Close the doors to other rooms, open an outside window or door wide and switch off unnecessary lights. Then step back and give it time: a bat usually finds the way out on its own. Do not try to catch a bat in flight.
Mainly spiders and flies. It often picks its prey off leaves and webs instead of catching it in the air. In some places it eats blood-feeding flies, which are plentiful in cattle sheds. It hunts low, in dense vegetation.
It is not threatened. Globally, and in Georgia's 2021 national assessment, it is rated Least Concern (LC), with a stable population. Still, it depends on caves, where it hibernates and breeds. So do not disturb sleeping bats in a cave.
References
What this profile is based on
Species profiles are compiled from peer-reviewed literature and established biodiversity databases, and are reviewed as new taxonomic and conservation data become available.
Prepared by the Reptiles.ge editorial team from the sources listed here.
