This report covers the period 1997-2008 of the NBMP. The primary aim of the programme is to produce statistically-defensible population trend data for resident UK bat species

Effective bat conservation relies on gathering information to identify changes in populations that are of conservation concern.

The main monitoring techniques employed by the programme are the Field, Waterway, and Hibernation Surveys and summer maternity Colony Counts.

Newer monitoring techniques involve the use of broadband bat detectors to record a range of species along roadsides and woodland transects.

Volunteer surveyors collect data and are supported by the monitoring programme through training workshops and the office team.

In 2008, 1018 volunteers took part. This is an increase of 2.6% compared to 2007.

The total site network now stands at 4,639. In 2008 a total of 1,991 sites were monitored of which 77.6% were repeat sites. There has been a 1.4% increase in the total number of sites monitored compared with 2007.

At present sufficient data are collected to produce population trends for 11 of the UK‟ 17 resident bat species.

Significant positive trends were reported for the greater horseshoe bat (Colony Count), lesser horseshoe bat (Hibernation Survey & Colony Count), Natterer’s bat (Hibernation Survey), common pipistrelle (Field Survey), and, for the first time, whiskered/Brandt’s bat (Hibernation Survey) and noctule (Field Survey).

The greater horseshoe bat, whiskered/Brandt‟ bat and noctule trends should be treated with caution at present.

In 2007, brown long-eared bat showed a significant increase for the first time from the Colony Count but this is no longer the case due to low counts in 2008.

Significant negative trends were reported for common pipistrelle and soprano pipistrelle (Colony Counts) though these may be highly influenced by the mobility of these species. The Field Survey showed a significant increase for common pipistrelle and a stable trend for soprano pipistrelle and these trends are presently considered more robust than the Colony Count trends for these species.

Data have contributed to UK BAP reporting and the national report to EUROBATS. NBMP staff have participated in UK and European knowledge-sharing workshops.

In May 2008, NBMP data enabled bats to be incorporated into the UK Biodiversity Indicators which help measure progress towards the Government's target of halting biodiversity loss by 2010.