The Comb-Crested Jacana’s very long toes and
claws spread its weight over the floating water-lily leaves. From
this platform, it hunts aquatic insects. Because it sometimes appears
to be walking on water, it has also been given the name ‘Jesus
bird’. In flight, it trails its long feet behind its body and
moves them to help with steering. They are also capable swimmers.
Males and females look the same although the females are a little
larger. The brightness of the distinctive crest depends on the mood
of the bird.
They feed on a range of plant material, especially seeds of water
lilies, and a wide range of invertebrate animals (mainly aquatic).
In the Top End, Comb-Crested Jacanas breed late in the wet season,
in the season that the Bininj/Mungguy people call Gudjewg. The males
build small nests of leaf scraps on top of the floating water-lily
leaves. A clutch of four small eggs is laid, these having markings
that camouflage them to resemble the nesting material.
The biggest threat to survival occurs at the egg stage. The hatching
rate is very low with many eggs being lost (mainly to predators).
Breeding success is enhanced by the female laying several small eggs
(rather than fewer, larger ones) and by females having several mates
incubating clutches of their eggs. So, unusually for a bird, it is
the male alone that incubates the eggs although the female does help
to defend the territory. Larger females produce somewhat larger eggs,
improving success if the eggs survive predation.
About four weeks later, the eggs hatch and the males tend the young.
When threatened, the males use their specially-shaped wings to carry
away the chicks.
Different species of the Jacana family occur in the tropics around
the world and in southern Africa. The Comb-Crested Jacana is found
across the top of Australia where rainfall is high in summer and
low in winter: from near Broome in WA to near Sydney in NSW.
This bird was photographed in Kakadu National Park.
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