Bromley biodiversity species action plan: bats (all species)

Bats are the only mammals that have evolved powered flight. They are long-lived intelligent animals with a complex social life. Bats are active at night, finding their way around and catching their food using an ultrasonic method of navigation known as echolocation. British bats are insectivorous, taking a huge variety and number of different prey items - thus they are important pest controllers. Bats need safe summer roost sites for rearing their young, good feeding areas with plenty of insect food, and safe undisturbed sites for hibernation in winter. They rely to a greater or lesser extent on trees but some bats prefer to roost in buildings including houses, churches and barns. The complex life style of British bats and their insectivorous diet means that their presence in an area is indicative of a healthy and diverse environment.

Twelve of the eighteen species of British bat occur in Bromley, of which 8 are almost certainly breeding in the borough. Two Pipistrelle species (Pipistrellus pipistrellus and P. pygmaeus) are the most common and ubiquitous of bats in LBB.

Data from the National Bat Monitoring Programme suggests that the populations of most bat species in the UK are stable or increasing from the baseline data of 1999 when monitoring on a national scale commenced. Detailed surveys in London reveal that there has been a significant decline since the 1980s particularly for Serotine, Noctule and Leisler bats (Guest et al. 2002) Bats in Greater London. Unique evidence of a decline over 15 years. British Wildlife 14 1-5.

All bats and their roost sites are fully protected by UK law.

Threats to bats in London Borough of Bromley

• Loss of maternity roost sites in buildings and/or trees
• Ignorance or intolerance of the public to bats
• Loss of and disturbance to other roost sites including winter hibernation sites (mines, ice houses), and other seasonal roost sites (buildings (roof spaces), bridges, trees, ivy-covered structures).
• Loss of insects due to inappropriate management of insect-rich feeding habitats such as grassland, woodland and wetland.
• Disturbance to commuting routes – may be due to loss of or inappropriate management of flightline features such as trees, hedges, river corridors
• Predation especially by the domestic cat.

Conservation status

• All bats and their roosts have full legal protection under Schedule 5 of the Wildlife and Countryside Act 1981 (as amended).
• Whiskered/Brandt/Alcathoe, Noctule, Soprano Pipistrelle and Brown Long-eared bats are Section 41 species of principal importance under the NERC Act.
• IUCN Red Listed species: Serotine - Vulnerable; Leisler - Near Threatened; Nathusius Pipistrelle – Near Threatened.
• Noctule, Soprano Pipistrelle and Brown Long-eared bats are Priority Species under the UK Post-2010 Biodiversity Framework.
• All bats present in Bromley are London and Bromley Priority Species.

Actions carried out 2015-2020

• Several local surveys were carried out for the National Bat Monitoring Programme (NBMP) organised by Bat Conservation Trust (BCT) and Joint Nature Conservation Committee (JNCC).
• Serotine roost counts (2015-2020) were carried out annually.
• Surveys for the Woodland Small Myotis Project using harp traps (under licence) and static recorders were carried out in selected woodlands in the Borough in 2018-2020.
• Surveys for the Nathusius Pipistrelle Project using harp traps and sonic lures (under licence) were carried out in Kelsey Park in 2017.
• Hibernation surveys – three underground winter hibernation sites are monitored each winter as part of the NBMP (under licence).
• Bat box checks – there are several bat box schemes in the Borough parks and green spaces with checks carried out in spring and autumn (bats handled under licence).
• Bat walks and talks are led for Friends’ Groups, youth organisations, and the general public over the summer months.

For further information about bats see Bat Conservation Trust website www.bats.org.uk