| Summary: | Insectivorous bats face fragmentation and loss of suitable habitats. Bats numbers are declining in several parts of the world and scientists aim to construct distribution models that can predict occurrence, in order to understand species habitat requirements. Significant correlation has been found between species and habitat attributes but conditions differ across the world and between species. A predictive model will not work as well somewhere else. Bat occurrence in Vara, Alingsås, Vårgårda and Borås municipalities is only briefly inventoried. The aim of this study is to investigate if chosen habitat attributes affect bat occurrence in these municipalities. Inventories from wind energy establishments were used, and nine species were found. Multiple linear logistic regression analysis were used to compare species occurrence with vicinity to water, trees with special qualities “Skyddsvärda träd”, nature reserves, area of deciduous forest and urban area, and aspect. Five significant results are consistent with previous knowledge; positive effect of vicinity to skyddsvärda träd and small area of open habitats for Myotis brandtii/mustacinus and positive effect of vicinity to urban areas for Nyctalus noctula and Vespertilio murinus. Four significant results contradict known behaviour or cannot be explained. There is also a non-significant positive trend of vicinity to water for seven species. The results are unclear with low reliability. Type of bat activity is not known. Habitat requirements differ whether the area is used for roosting, hunting or transport, which is important to consider when “occurrence” is defined. Data was not collected at the same time of the year which affects both activity and species occurrence. This type of analysis along with modelling is a cost-effective way to monitor bat dispersion. Studies in other countries have found predictive correlations and this study can be improved. Therefore it should be possible to generate more accurate analyses in future Swedish studies. Insektsätande ...
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