VWTImpactReport28Oct2025PT - Flipbook - Page 14
©Daniel Hargreaves
4
Horseshoe bats in buildings
— helping to increase horseshoe bat populations in Britain and Ireland
What is VWT’s impact?
Our roosts now protect 50% of the greater horseshoe
bat population in Britain, 10% of the lesser horseshoe
bat population in Britain, and 25% of the lesser
horseshoe bat population in Ireland.
Under VWT’s management:
• Between 1999 and 2020, greater horseshoe bat numbers
at VWT roosts in Britain have more than doubled
compared with the national average across all roosts.
• Lesser horseshoe bats at VWT roosts in Britain have
increased by 3.5 times that of other roosts.
• In Ireland, populations of lesser horseshoe bats
at VWT-managed roosts have increased while
other roosts remained stable.
Why is there a need?
The greater horseshoe bat and the lesser horseshoe
bat are the only horseshoe bat species in Britain,
with only the lesser horseshoe bat in Ireland.
later, the reported British population of greater
horseshoe bats had drastically reduced by 98% to
around 2,200. Historical numbers of lesser horseshoe
bats are unknown but by 1995, the population
was estimated to be around 14,000. The earliest
population estimate for lesser horseshoe bats in
Ireland is from 1985, with an estimated 12,000 bats.
In Britain, habitat loss, intensive agriculture with
increased use of pesticides and the loss of insect prey
led to the drastic declines in the greater and lesser
horseshoe bat populations at the beginning of the 20th
century. In Ireland, deforestation, which reduced
woodland from 80% across the island of Ireland to only
1% by 1925, has impacted lesser horseshoe bats through
the loss of woodland cover and feeding sites.
The reliance of these two species on disused pre-20th
century buildings, many of which became derelict
or were re-developed, also makes them vulnerable
to building repair work, re-roo昀椀ng and the use of
toxic timber treatment chemicals. In addition, lesser
horseshoe bats are one of the most light-averse bat
species, making them particularly vulnerable to
urbanisation and arti昀椀cial lighting.
In the 19th century, Britain’s greater horseshoe bat
population was estimated to be 110,000 animals. A century
VWT Roosts
(Britain)
VWT Roosts
(Britain)
The rate of recovery for horseshoe bats is slow
and may be further affected by new challenges
thrown up by climate change, in addition to
threats of habitat loss, population fragmentation,
urbanisation and declining prey availability.
VWT Roosts
(Ireland)
Greater
horseshoe bats
Lesser
horseshoe bats
Lesser
horseshoe bats
366%
188%
217%
14
Vincent Wildlife Trust 50 Years Impact Report 2025
©Daniel Hargreaves
Following the legal protection of breeding roosts in 1975,
VWT is safeguarding in perpetuity 30 lesser horseshoe bat
roosts in Britain and Ireland, and 7 greater horseshoe bat
roosts in Britain. In addition, it is managing an additional
8 signi昀椀cant roosts to ensure increased connectivity and
extended range for horseshoe bats in Britain and Ireland.
Increasing the scale of our work on these
species will help ensure that we stay
ahead of new challenges.
