Last week I completed a couple of days surveying with SLBG , aiding out in there flagship annual survey conducted in the Kirklees Valley.
The Millpond survey has been running at the same site since 1994 and has amassed a considerable amount of data applicable to bat conservation within the region.
The structure of this ongoing project required each pond to be surveyed over a 75 minute period. The first hour, beginning at sunset, consisted of a typical survey in which factors such as number of individuals, species presence and activity type of bats were recorded. The latter 15 minutes took a different approach. The aim here was to quantify the level of bat activity at the site, the idea being that activity recorded within the 15 minute slot could be used as a proxy for average bat activity at each pond. To collect this data, the 15 minute time slot was divided into 90 lots of 10 second intervals during which a presence/absence tally could be conducted for each species. Any species activity within each 10s interval, regardless of its intensity, counted as one tick. As such any one pond could have a score ranging from 0 to 90 for each bat species. Such a methodology allows non-biased, non-subjective collection of activity data.
This year the survey involved 29 ponds, one lower than the previous year due to a transitional pond finally succumbing to succession into marshland. Only through successive years of data collection can the effects of such habitat change be quantified, allowing appropriate management to be conducted.
Over my two days of participation I noted 3 species; Common and Soprano Pips, and Daubenton’s. A further 3 more; Whiskered/Brandts, Brown Long-Eared and Noctules were observed by my colleagues at other ponds, a great range of species for such a small survey area.