82 Australian Geographic
Dusky leaf-nosed bats (Hipposid-
eros ater) are tiny, growing only up to 6.5cm
and 11g. They go in search of food after sunset
and are recognised by their large, rounded ears.
Sooty grunters (Hephaestus fuliginosis) are
also known as black bream; they are grey-black
or golden brown with dark blotches on rear fi ns.
Growing up to 50cm and 4kg, they are found in
streams with sandy or rock bottoms.
Saltwater crocodiles (Crocodylus
porosus) have been known to venture upriver
during the wet season. But the rangers search
for them before opening the river to canoeing
and swimming, and any found are captured
and removed.
Freshwater crocodiles (Crocodylus john-
stoni) are far less sure of themselves, to the point
of shyness. But be careful you don’t intrude near
a nesting site as they will defend with a snap.
White bush apple (Syzygium forte
ssp. potamophilum) grows to 30m. Its bark is
papery, fl aky and reddish and the dark leathery
leaves can be bluish; it has white fl owers and
cream-white apple-like fruit, a food for the
Jawoyn and fi sh and turtles.
Darters (Anhinga melanogaster), or snake
birds, dive from the air to capture their prey in
dagger-like bills. They can remain underwater for
up to a minute; their plumage is not waterproof
and they have to dry off before fl ying.Northern snake-necked (Chelo-
dina rugosa) and short-necked turtles
(Emydura victoriae). Together, the head and
extended neck of the northern snake-necked are
longer than its body; the short-necked has pale
salmon stripes on the side of its head. You can
see them sunning on rock ledges near the water.Little pied cormorants (Phalacrocorax
melanoleucos), with dull yellow bills and pale
under-plumage, and little black cormorants
(Phalacrocorax sulcirostris) duck-dive for their
prey. They too must dry off before fl ying.Barramundi (Lates calcarifer) can grow
to more than 1.5m and 60kg; the minimum
legal size for catching them is 55cm. Silvery,
with a pointed head and protruding lower
jaw, nearly all are born male, changing sex to
become female after about fi ve years.Freshwater mangroves (Barringtonia
acutangula) grow to about 8m and are decidu-
ous. Their red fl owers have long stems and their
unusual fruit is four sided. The tree is regarded
as poisonous and the bark is pounded to use as
a fi sh poison by the Jawoyn.Fairy martins (Hirundo ariel) migrate to
breed at Katherine Gorge every year. They feed
on insects, look similar to small swallows, and
build bottle-shaped mud nests in rock overhangs
and caves.River pandanus (Pandanus aquaticus)
grow up to 4m in clumps with prickly elongated
leaves and are always associated with freshwater
streams. Its globular, green fruit turn orange
when ripe and the inner fl esh is eaten by the
Jawoyn, who use the leaves to make string.Mertens’ water monitors (Varanus
mertensi) are strong swimmers and can stay
submerged for long periods. They grow up to
1m and have distinct, light-cream to yellow
spots and narrow cross-band markings. They,
too, like to sun themselves.2.6.7.3.5.4.1.Species to spot
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