Information below is from Lynda Stakers book " Don't step backwards" ( with permission )
Grey Kangaroos are the most social of the large macropods. The Eastern Greys
frequent the eastern side of Australia, whereas the Western Grey
frequents the south and south-west of Australia. Eastern Greys have a longer
gestation period, and pouch life than the Western Greys, and they are a light
greyish/brown, compared to the Western’s copper brown colour.
As with many of the macropod family, the fertilised egg from a mating does not
develop until the joey she already has in pouch vacates the pouch
permanently at about 12 months. This fertilised egg develops only to the stage
of a blastocyst, until the joey in pouch vacates the pouch permanently.
By the time the out of pouch joey is weaned at around 18 months, the joey in
pouch is around 8 months old. Greys can hold their blastocysts from further
development in drought; this process is called embryonic diapause.
Unfurred macropods can be distinguished from other species by their ‘meaty’
little upper lip, high forehead, and long finger and toe nails. Compared
to wallabies, they have very long legs. Their eyes do not open until around the
five months stage, which is longer than any other macropod.
Being so social, Greys should never be released on their own! They should be
integrated into a mob, and released no sooner than 17-18 months old.
The dominant Grey male is probably the most aggressive of the kangaroos, when
his dominance is threatened, or when a female is on heat. Females rarely
show aggression, although they will not tolerate another mum’s joey.
It is quite common to see joeys with pieces out of their ears, after
going up to the wrong mum. Mothers make a soft clucking sound to call their
young, both sexes emit a loud gutteral cough, either when alarmed, or when the
male concedes to another.
Greys are susceptible to many fatal diseases, so a good knowledge of disease
is required for their captivity.
Not every male is born to be the “KING” or the dominant male. In my observations,
only a very few males are ever born with the aptitude of being boss of a mob.
Most males who are not dominant take an easy approach to life in the mob,
by staying clear of the dominant male, and mating with a female when the ‘boss’
is not looking!
Males do not develop their muscular bulk until around 7 years of age, and an
adult can weigh up to 70 kg, which is huge in comparison to the female
weighing up to only 32 kg.
Licking forearms in hot weather is a way in which macropods cool themselves.
Saliva drips onto the forearms, where there is a network of superficial
blood vessels, with an increased blood flow in hot weather. The wetting of this
area ‘cools’ the blood flow, thereby allowing considerable heat loss.
If managing large Grey kangaroos in captivity, never turn your back on a
dominant male, as this practise will most likely see you lying face down
in the dirt, with a rather large fore paw on your back! Never trust a large male,
completely, have a mutual respect for an animal who is quite capable of doing
serious injury to you.
The best way to approach captive Greys, is to offer your hand down between their
arms, and touch their chest, as they will feel threatened if you try to
‘pat’ their head. Friendly females will usually arch their heads back, beckoning
a scratch on the chest and under the chin. From adolescence onwards, males
have a beautiful smell all of their own. It smells like ground coffee beans,
and is most prominent on their backs.
In captivity, when Greys feed amongst other macropods, they tend to be the more
passive, compared to other species. Rather than upset the apple cart,
they prefer to just get on with eating their food in peace. Feed time is the
best time to tick macropods, as they are totally at ease whilst their minds
are on eating. The best way to tick them is to straddle them from behind, but
be warned, don’t put your head down close to their backs, as, if spooked,
their head comes up at neckbreak speeds, and is likely to break your nose!
Information below is from Lynda Stakers book " Don't step backwards" ( with permission )