Figure 1.
a) the study area within the state of New South Wales, Australia b) the position of the 32 study sites within the study area, with the linear remnant network shown in white c) an example of the layout of four survey points nested within a study site d) a bat detector, in a weatherproof box and with microphone funnel attached, on a platform strapped to a survey tree, and e) a black-light trap on the ground.
Figure 2.
Mean dry biomass of arthropod samples collected per night in each of the land-use classes.
Error bars represent 95% confidence intervals, and sample sizes are listed below each of the plotting points.
Table 1.
Bat species recorded in the surveys.
Figure 3.
PCA biplot with loadings of the five vegetation measures on habitat components 1 and 2.
Habitat component 1 separates sites according to condition, ranging from ‘intact’ (more negative scores) to ‘degraded’ (more positive scores) Habitat component 2 related to site structure: ‘shrub/grassland’ in the negative values to ‘grazed/cropped woodland’ in the positive values. Survey points are plotted according to the land use class that they occur within.
Table 2.
Groups of explanatory variables used to construct the alternative generalised linear mixed models predicting bat species richness, activity and feeding (see Table 3, Table S3).
Figure 4.
The relationship between bat responses and arthropod biomass, in both remnants and fields.
Parameters from the Spearman-rank correlation analysis of each relationship are listed on the plots, and a smooth curve has been fitted for visualisation.
Table 3.
95% confidence tables resulting from analyses of bat responses in remnants and fields.
Table 4.
Relative importance of each variable group in each of the analyses.
Figure 5.
Influential predictor variables for bat responses.
a) bat species richness in remnants, b) bat activity in remnants, c) bat feeding in remnants, d) bat species richness in fields, e) and f) bat activity in fields. More positive values of habitat component 2 indicate that a site has a structure which closer resembles a grazed or cropped woodland (mote trees, hollows and logs), as opposed to a shrub/grassland. Model parameters are listed in Tables 5 and 6). Semi-transparent polygons depict 95% confidence intervals.
Table 5.
Model parameters predicting bat species richness, activity and feeding in remnants, showing the coefficient, standard error (SE), and lower and upper 95% confidence intervals (CI upp and CI low respectively) for each variable in the final model.
Table 6.
Model parameters predicting bat species richness, activity and feeding in fields, showing the coefficient, standard error (SE), and lower and upper 95% confidence intervals (CI upp and CI low respectively) for each variable in the final model.