FAMILY:
Cacatuidae
GENUS: Callocephalon
SPECIES:
fimbriatum
Description:
Small
to medium cockatoo with dusky grey body plumage which is narrowly scalloped in
dull white and a scarlet head.
Females and immature birds are dull grey (often with a greenish tinge). Females
often have orange barring on the chest. Both sexes have a "feather-duster" crest
which they are unable to raise.
Immature birds resemble the female Gang-gang
in body plumage. However, all males carry some red colouring on their heads. The
extent of this colour varies considerably between birds however.
Length:350mm.
Distribution:
Restricted
to south eastern maniland Australia from Portland (Vic.) to Blue Mountains
(NSW).
It has been introduced on Kangaroo Island and has been recorded as a vagrant in
Tasmania. Since European settlement it has declined in number and is now
considered to be most common in the southern highlands.
Habitat:
Tall
eucalypt forests and adjacent woodlands.
Also in suburban parks and gardens.
Diet:
Eucalypt
seeds, fruits and insects and the fruits of the introduced hawthorn. Food
sources are usually exploited until exhausted.
Breeding:
From
September to January.
The
usual nesting site is a tree cavity in a eucalypt near water. Both the male and
female prepare the nesting site, and both share incubation and care for the
young.
Gang-gangs
usually prefer vertical nesting logs with an internl diameter of about 30cm with
entrances at the side near the top. However, they have also bred successfully
in nesting boxes of about 30cmx30cmx50cm with a spout entrance near the top.
The preferred nesting material is a mixture of wood shavings and dirt or peat
moss.
Courtship
Display
This
is most often performed very near or at the entrance of the nest hollow. The
male calls to the female with wings spread and body held fully erect. Like other
cockatoos, his behaviour becomes rather excited. A receptive female will usually
fly to the hollow entrance and inspect it. This may be accompanied by some
chewing at the hollow's entrance. Copulation follows shortly afterward.
Sexual
maturity
This
species becomes sexually active at about 4 years of age.
Clutch:
2
white oval eggs. Incubation period: about 20 days. Fledging usually occurs at 40
days, but young remain dependant for 4-6 months.
Mutations
and Hybrids:
There
is one reported case of a cinnamon mutation in the wild.
Hybrids have been
recorded with Galahs and Corellas.
Suitable
Aviaries and Compatible Birds
As
a minimum, a single bird may be housed in such a cage provided it measures at
least 800mm x 600mm x 1200mm (approximately). Pairs can be kept in a slightly
larger cage. However, these birds always fare better (and look more spectacular)
in larger aviaries. These should be somewhere in the vicinity of 2m wide x 2m
high x 5 or 6m long so as to provide amply flight space and to accommodate
nesting logs etc.
The wire should be of a heavy duty grade, as cockatoos
easily chew holes in lighter grade wire. Similarly, the frame should be
constructed of steel to avoid the birds chewing the structure away.
This
cockatoo is particularly fond of chewing (especially young birds) and require
regular supplies of large leafy branches (preferably with gum-nuts) which they
will strip in no time at all. Branches should also be placed in the cage/aviary
such that it produces a climbing complex similar to the structure of a
tree-crown. This provides the birds with an extra distraction and helps to
relieve boredom.
Species
Specific Problems
Gang-gang
cockatoos usually prefer not to spend too much time on the ground. However, many
young (and some mature) birds have been seen spending a con siderable amount of
time on the ground. This behaviour makes them susceptible to infection with
intestinal worms and fungi. These are relatively easily dealt with however
simply by maintaining a high standard of hygiene.
Another problem
encountered in this species is Psittacine beak and
feather disease. This is an incurable disease which is transmitted through
feaces. Essentially, it results in poor feather growth and feathers which don't
replace themselves when they fall out. Similarly, the beak is also affected and
becomes fragile and does not repair itself.
It is advisable to test birds
suspected to have this condition. The best course of action for affected birds
is to destroy them as there is no cure. Infected birds will infect their
offspring simply by feeding them as there is always
chances of contact with faeces in the nest and during feeding of the
young.
Feather plucking is also quite common in Gang-gang Cockatoos. This has
a range of causes and can usually be rectified (see our articles in the "Regular
Features" section of our website). However, personal experience suggests that
this is a problem caused by boredom or perhaps trauma. The most likely scenario
is that the birds are not being supplied with ample chewing materials (branches,
nuts, leaves, etc.) or that their aviary is not suitably set up. (see
above).
It has also been suggested that plucking arises out of an
incompatibility between mates. This may arise from "sexual frustration" or
indeed simply because the two birds don't get on and stress one another.