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11.3.46 Myotis bat calls accounted for 3% of the calls recorded during the transect surveys. These
were recorded by the northern-most pond during the September transect walk. The calls were
considered most likely to be Daubenton’s bat, given the flight behaviour observed and call
features recorded, but this could not be confirmed.
11.3.47 A small proportion (approximately 5%) of recorded bat calls could not be identified to species
level. These calls were classified as pipistrelle bat (likely to be soprano or common pipistrelle),
Myotis species, or unidentified bat species. Brown long-eared bats may also been visually
observed on site during the July transect, based on observed flight behaviour, but no calls
were heard or recorded and so their identity could not be confirmed.
Driven Transects
11.3.48 The driven transects recorded a low level of bat activity, with soprano pipistrelle being the only
species recorded
Dusk Commuting watches
11.3.49 The dusk commuting watches revealed a very low level of bat activity throughout the six
months of survey work.
11.3.50 No commuting routes were evident; and no noctule bats were encountered.
Automated ANABAT Recording Surveys
11.3.51 The results from the Automated Anabat Recording Survey confirm the transect survey results
regarding species using the site as well as usage of the site by these species, however the
average activity levels recorded were lower than during transect surveys.
11.3.52 The two Anabats on site in the maternity season (between 15 and 28 July) show similar
species composition and activity level. Activity at the Anabat placed in the north of the site
starts earlier than at the Anabat placed in the south of the site (Figure 11.2) which could
indicate that a seasonal roost site could be near the north of the site.
11.3.53 The data recorded by the two Anabats (C and D) during the dispersal period (30 August to 14
September) shows a similar species composition for the site, but with slightly more activity of
Myotis bats. However the overall bat activity appears to be much higher than during the
maternity season, which may reflect the increased bat population once the young of the year
are able to fly. However, it is considered that the higher levels of recording by Anabat C may
simply reflect one or two individual bats which made regular foraging passes by the detector.
Such behaviour was observed by surveyors during walked transect surveys, with an individual
bat flying in repeated loops by small trees or scrub for many continuous minutes.
November 2010 Chapter 11 Page 23
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