“Species share roosts sites, but segregate spatially within”
Observations from previous studies commonly report co-occupation of
roosts by multiple species, with anecdotal observations of inconsistent
overlap or separation within and between trees (Table 2). We observed
some horizontal spatial segregation of species, with species showing
preference for discrete areas in roosts. In the ‘Lismore’ roost, for
example, black flying-foxes were commonly distributed toward the eastern
part of the roost and grey-headed flying-foxes in the western part of
the roost (Appendix S3). Likewise, in the ‘Clunes’ roost, black
flying-foxes were commonly observed toward the north-eastern part of the
roost and grey-headed flying-foxes in the south-western part of the
roost (Appendix S3). Of 659 occupied subplots across the survey period,
only 34.1% (225, binomial confidence interval: 0.31-0.38) showed
co-occupation by two different species (Figure 6A). Co-occupation of
individual trees by two different species was also relatively low –
across surveys where two species were present, 4.6%-7.9% of occupied
trees were co-occupied by two species, versus 92.1-95.4% that were
occupied by only one species (Figure 6B). Only six trees were ever
observed to occupy all three species at once.