The Vertebrate Fauna of Jenolan Karst Conservation Reserve: Final

Cook visited after limited installation of primitive electric lighting. In unlit caves magnesium ribbon or
torches of stringybark dipped in tallow was used for illumination - a practice that had been going on
since the 1850’s and undoubtedly would have disturbed the bats from the smoke and light emitted.
These observations give some indication of how the distribution of bats has changed since visitation
by Europeans began, though it is possible that even by the 1880’s that some bats had already been
displaced.
Other reports of bats are scant, but a newspaper article describing a visit to the caves in 1898
mentions bats ‘infesting’ Jubilee Cave (The Mercury 1898), a tourist cave where bats no-longer occur
in any numbers. This disparaging attitude was typical of the time and likely the reason so little
attention was given to reporting their occurrence.
There are anecdotal reports of large numbers of bats in Bat End Chamber prior to the quarrying of the
Binoomea Cut in 1954. Tour groups would approach from River Cave and disturb the bats which
would fly ahead of the tourists to the chamber, at which point the animals had no choice but to turn
around and fly directly at the group. It is possible that these bats were displaced from River Cave or
the numbers may have been exaggerated over time. Either way, the large numbers recounted would
suggest they were eastern bentwing-bats which are not found in either location in the present day.
Large guano deposits are present in the River Cave (A. Musser pers. comm.), proving that this
location was at some point in the past an important site. It is unknown if this site was a maternity roost,
however analysis of skeletal remains may give some clues to the historical importance of River Cave.
An overall reduction in the number of bats roosting in the caves has been noticed since the 1970’s (B.
Richards pers. comm.). However bats may vary roost locations seasonally and anecdotal accounts
may not correspond with actual population trends. This decline corresponds with declines that have
been reported across Australia during this same timeframe and may be unrelated to cave
management. Removal and modification of cave gates in the 1980’s benefited cave-dwelling bats, and
following this bats have recolonised some caves including Upper Imperial Cave (A Spate pers.
comm.).
9.2.3 Birds
No birds in NSW are obligate cave-dwellers.
Australian birds generally only exploit cave
entrances, the cliffs above cave entrances and
the twilight zone; the exception being the whiterumped
swiftlet (which is predominantly known
from north-eastern Australia), which uses
echolocation to navigate dark caves (Coles et al.
1987). However, many birds use caves for
shelter and nesting and will feed on the
abundance of insects typical of cave entrances
(Hamilton-Smith 1965). At Jenolan Caves, the
sooty owl and rockwarbler are closely associated
with the caves and their populations are
dependent on them. The sooty owl is a
threatened species and is discussed in detail in Rockwarbler roosting in a cave. Photo © M. Schulz
section 5.
At Jenolan, sooty owls nest and roost in the Devil’s Coach House (Hollands 1991) and associated
caves. During the current survey, owl pellets were also observed in Arch Cave and Nettle Cave. Owls
favour twilight zones, not only for shelter but possibly due to availability of food such as bats and small
mammals. Protection of nest sites from the sun, temperature fluctuations, wind, rain and predators are
also probably important factors (Hamilton-Smith 1965). Barn and masked owls have been recorded
nesting in caves elsewhere in Australia, though this has never been observed at Jenolan.
Rockwarblers and superb lyrebirds are well known to favour caves and overhangs for nesting.
Rockwarblers have been recorded in the Devil’s Coach House and previously nested in Nettle Cave
(Hamilton-Smith 1965); though they appear to have recently declined at JKCR (I. Eddison pers.
comm.). Some further examples of non-obligate cave-dwelling birds from Jenolan Caves include the
welcome swallow, fairy martin, grey shrike-thrush and white-throated tree-creeper. Welcome swallows
commonly nest in twilight zones and on cliff faces, as do fairy martins (Hamilton-Smith 1965). Grey
shrike-thrush favour cave entrances due to high insect activity and white-throated treecreepers roost
in cave entrances and have been reported foraging on insects in almost complete darkness 50 metres
into caves (Hamilton-Smith 1965). Peregrine falcons, nankeen kestrels, spotted pardalotes and grey
shrike-thrushes will also nest inside cave entrances (Hamilton-Smith 1965).
The Vertebrate Fauna of Jenolan Karst Conservation Reserve 113