Prey Analysis

To help us build a better understanding of bat foraging behaviour and what specifically they are feeding upon, aquatic invertebrate surveys were carried out by Craig Macadam of Bradan Aquasurveys Ltd. This work consisted of a systematic search of the marginal vegetation at selected sites, followed by a scoop of the sediments on the canal bed.

The initial results showed that the canals hold a healthy population of aquatic invertebrates, however the majority of these live solely within the water and would therefore not be available prey for bats.

Aquatic insects, the potential prey for foraging bats, were well represented with ten separate families recorded. The most common of these were the non-biting midges, Chironomidae. These small insects are well known prey for many species of bats and it was anticipated that they would make up the majority of specimens found. The samples collected were identified to species level, thus allowing flight periods, adult sizes, and hence the potential for the species to be a prey item for bats to be determined.

Our research included the following areas of study :-

• Analysis of bat faeces to establish prey consumed.

• Aquatic invertebrate surveys.

• Water quality using Average Score Per Taxon modelling.

• The relationships between bats and their associated ectoparasites