Wednesday is the day I bring you an Australian bird and today it is the turn of the Radjah Shelduck -Tadorna radjah, also known as the
Burdekin Duck in Australia. The genus name Tadorna
comes from Celtic roots and means "pied waterfowl", essentially the
same as the English "Shelduck".
Both the male and female of the species are mostly
white, with dark wing-tips and a distinctive "collar" of dark
feathers. Seen from above in flight the birds have green bands on the tops of
their wings. The female has a harsh rattle and the male has a breathy,
sore-throat whistle.
Size 49–61 cm.
In
tropical dry season these large dumpty Shelduck flocks congregate on mangrove-lined river channels, tidal
mudflats and beaches, or remain inland on permanent lagoons.
In wet season
moves from littoral habitat to the shallow margins of the expanding wetlands.
Flight swift and powerful; dashes fast and low between trees. Very vocal, calling in flight, on water or land.
The species prefers the brackish waters of mangrove
flats and paperbark tree swamps, but will visit freshwater swamps, lagoons, and
billabongs further inland during the wet season.
The Raja Shelduck forms long-term pair-bonds, and is
usually encountered in lone pairs or small flocks. During the wet season the
males commonly become very irritable, and have been observed attacking their
mates.
The diet consists mainly of mollusks, insects, sedge
materials and algae. Pairs start searching for nesting sites during the months
of January and February. They nest close to their primary food source, often in
the hollow limbs of trees, which makes habitat destruction a particular issue.
Breeding
Territories are occupied at start of wet season. Most eggs are laid April –June so that ducklings have optimum feeding areas as flood waters recede. Nest is a large tree hollow chosen by the pair and lined with down; same site probably used each year.
Clutch 6–12. Incubation time is about 30 days. After ducklings leave nest they are attended by both parents and remain together in a family group throughout the following dry season .
The Radjah Shelduck inhabits the mangrove forests and
coastline of New Guinea and Australia. In Australia, its primary range is
coastal tropical northern Australia, from central Queensland through northern
Northern Territory (including Kakadu National Park) to the Kimberley in Western
Australia.
The Raja Shelduck is listed as a protected bird in all
states of Australia and penalties exist for harming or disturbing them.
I hope you enjoyed hearing and seeing the Radjah Shelduck.
Thank you for visiting.
I appreciate all your comments and I thank you for everyone of them.
