Nathusius’ Pipistrelle Bat – Pipistrellus nathusii

Taxon: Chiroptera
Habitat: Riparian, Woodlands, Estuaries
Description: A medium-sized bat with dark brown to chestnut coloured fur on their back and lighter brown on their belly.
Size: Medium-sized pipistrelle bat.
Weight: 5.5-11g
Origin & Distribution: Native. Widespread across the UK. Most records are from solitary individuals.
Diet: Aerial hawker (feeds on the wing) preying mostly on flies and moths.
General Ecology: Associated with riparian habitats, favouring large water bodies with associated woodlands, estuaries, and large managed gardens. They exhibit rapid and direct flight patterns. A long-distance migrant, often travelling along coastlines, and activity peaks in these areas are during September and October. Solitary roosts have been found in bat boxes, trees, and buildings. Hibernation sites are unknown, but a few individuals have been found in log piles and behind shutters on boarded windows.
Breeding: Mating roosts have been identified in bat boxes and buildings. Fewer than 10 maternity colonies are known and are from the East coast in buildings. Northern Ireland has a stronghold for this species with stable maternity colonies recorded in old stone buildings that have existed for over 20 years. A long-distance migrant with breeding areas in the North-East of Europe.
Conservation Status: Registered as Near Threatened in England and Great Britain, Vulnerable in Wales and Scotland, and Least Concern globally on the IUCN Red List. Evidence exists of a positive effect on Nathusius’ pipistrelle bat populations from climate change, due to an alteration to migration routes and summering/wintering grounds.
Identification
Compared to other pipistrelle bats, the Nathusius’ is a medium-sized bat. The fur is dark brown to chestnut coloured on the dorsal side and a lighter brown on the ventral side which extends down to the tail membrane. The wings are broad, sometimes bordered with a thin pale lateral edge. The wing cell that runs form the first joint of the fifth finger to the forearm is divided with a distinct vein. Males have a bulbous penis fringed with white hair.
Identification Definitions
- Dorsal: back, or upper side of an animal
- Lateral: of, at, towards, or from the side or sides.
- Tail Membrane: Skin connecting the tail to the feet.
- Ventral: on or relating, to the animal’s underside.
- Wing Cell: one of the areas surrounded by veins in the bats wing.
- Wing Membrane: An extension of the skin of the bats body which covers the wings.
Bat Detector
Range: 36-62 kHz
Most energy: 41 kHz
Average duration: 6.9 ms
Confusion Species
None.