Within-season changes in habitat use of forest-dwelling boreal bats.

Ville Vasko,Jon E Brommer,Kati M Suominen,Vesa Selonen,Veronika N Laine,Pekka Niemelä,Lasse Ruokolainen,Kai Norrdahl,Anna S Blomberg,Thomas M Lilley,Eero J Vesterinen,Andrea Santangeli

doi:10.1002/ece3.6253

Abstract

Bats utilize forests as roosting sites and feeding areas. However, it has not been documented how bats utilize these habitats in the boreal zone with methods afforded by recent technological advances. Forest structure and management practices can create a variety of three‐dimensional habitats for organisms capable of flight, such as bats. Here, we study the presence of boreal bats in a forest forming a mosaic of different age classes, dominant tree species, canopy cover, soil fertility, and other environmental variables, throughout their active season in the summer using passive ultrasound detectors. Our results indicate a preference for mature forest by Eptesicus nilssonii and a pooled set of Myotis bats. Both groups of bats also showed temporal changes in their habitat use regarding forest age. In June and July, both groups occurred more often in mature than young forests, but from August onwards, the difference in occurrence became less evident in Myotis and disappeared completely in E. nilssonii. In addition, E. nilssonii was more often present in forests with low canopy cover, and its occurrence shifted from coniferous forests to deciduous forests during the season. The results reflect the within‐season dynamics of bat communities and their ability to utilize different types of forest as environmental conditions change. Yet, the results most importantly emphasize the importance of mature forests to bat diversity and the need to conserve such environments in the boreal zone.

Highlights

To study the temporal variation in forest habitat use by bats, we used GIS-data provided by Parks & Wildlife Finland to coarsely divide the areas by age (60 years old as “mature”) and dominant tree species
Our study provides the first in-depth documentation of habitat use of bats in a boreal forest environment
TA B L E 3 The relationship between Eptesicus nilssonii occurrence and each of the five environmental variables considered as resulted from multimodel averaging

Summary

Introduction

To study the temporal variation in forest habitat use by bats, we used GIS-data provided by Parks & Wildlife Finland to coarsely divide the areas by age (60 years old as “mature”) and dominant tree species (pine, spruce, birch). The environmental variables used to predict bat presence were distance to closest waterbody, age of forest in 10-year classes, canopy cover, and proportion of deciduous trees in the forest.

Results

Conclusion