Why are Grey-headed Flying-foxes listed as 'vulnerable' when there are so many of them?

Grey-headed flying-foxes are now listed as 'vulnerable' to extinction, and their numbers are in decline. At the beginning of last Century there were millions of Grey-headed Flying-foxes, however, 100 years later, their numbers are now estimated to be less than 400,000.

Occasionally there is a significant flowering of Spotted Gum forests around Bateman's Bay or other localities, which can attract a large influx of grey-headed flying-foxes from across Australia's south east. Local residents are then under the impression that there is a population explosion of bats when really it is not the case. The large numbers of flying-foxes will disperse again in 2 to 3 weeks once the abundant flowering has finished.