The Western Grey Kangaroo
(Macropus fuliginosus*)
*see footnote

by

Bob Cleaver

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Macropus is derived from the Greek meaning ‘big-footed’ and fuliginosus meaning ‘sooty’.

There are a three extant subspecies:-

Macropus fuliginosus fuliginosus(*see footnote) – exclusive to Kangaroo Island, off the coast of South Australia.  

Macropus fuliginosus ocydromus – found in the vicinity of York in Western Australia.

Macropus fuliginosus melanops – confined to the Mount Lofty ranges near Adelaide, South Australia

General

At early settlement the Western Grey Kangaroo and the Eastern Grey Kangaroo were thought to be the same species and were once known as the Great Grey Kangaroo and was given the scientific name of what is now the Eastern Grey i.e. Macropus giganteus.      It was only as recently as 1972 that the two species were described separately after considerable scientific and reproductive evidence documented by J. A. W. Kirsch, and W. E. Poole.

These animals have a number of localized common names such as the Mallee Kangaroo, Sooty Kangaroo, Scrubbers and Stinkers.     Scrubber is used because they are animals commonly found in scrub land (the bush) but the term can be taken in a number of ways and can sound a little uncomplimentary.    Stinker is referring to the males, particularly the adult males, who have a very strong odour which once smelt is not easily forgotten.    In a captive situation it will disappear once an animal is castrated.    This aroma can sometimes be found on the females but I suspect that it is only after they have been in close proximity to an adult male.    Some people think it is a repugnant smell but talking personally I think it should be bottled.    I find it a very pleasant spicy smell and the best way I can describe it is that it is not unlike a sweet aromatic curry powder.

Appearance

The term ‘grey’ is a bit confusing as is the term ‘western’.     Firstly, they are not grey at all, but brown, or at least they are brown on the head, back, rump and tail.    Their underparts are generally white or off white and the paws, feet and tail tip are black or very dark brown.    As for ‘western’, they should really be called ‘Southern Grey Kangaroo’ as their range covers only parts of southern Australia.    They are not found in the tropics.      Adult full males would attain a weight of about 50 to 60 kgs (120 to 144lbs) with females about half that.    A castrated male will only reach female size.         The Kangaroo island subspecies is generally very much darker than its mainland relative with much less white on the underparts.    It is also of a much stockier build.

Distribution

These animals are found across much of the southern continent of Australia except the extreme east and Tasmania.     Their range extends from coastal regions of southern Western Australia across the Nullabor Plain and into South Australia where it frequents the southern two thirds of that state.    Its range then continues easterly into the western portions of New South Wales and Victoria and a very small portion of south central Queensland    At the eastern end of its range it overlaps that of the Eastern Grey Kangaroo (Macropus giganteus).      It is interesting to note that there have never been any wild hybrids found between the two species.    In captivity the Eastern Grey female has been known to produce a hybrid from a Western Grey male but strangely enough never the other way round.

Habitat & Diet

These are animals of lightly forested country but can be found in a variety of habitats from sclerophyll forests to a semi arid savannah.   They will spend their days dozing in the shade of the trees and shrubs and in areas where cover is sparse they will move with the shade as the day progresses.     They will come out to graze on native grasses at night and the early evening.   In tough times they will browse on shrubs and other edible herbage off the ground and will even migrate to suburbia where green lawns can be found.    Recreation areas, ovals and golf courses are favourite haunts.     In general the Western Grey does not generally cover the vast distances of the Red Kangaroo.   They tend to be sedentary and will not move far from their home range except in times of drought when they will cover a lot of ground in search of better pastures.     We have a resident mob that frequent our property and we see the same animals so often they become recognizable individuals.    We regularly sight a group of 15 to twenty animals and the most we have sighted at one time is fifty five.     Judging by their activities I would estimate that their home range would be two or three square kilometres.

Captive Husbandry

To maintain these animals in captivity you will need some room.    I am not going to suggest a minimum area as each individual animal is different and some will cope well with a relatively small area but others will not but in general a standard house block is not big enough.      What I will say is that they should be on an area that gives them the chance to sprint around without crashing into anything.    Young animals particularly, seem to like charging about at great speed for no particular reason other than sheer youthful exuberance.     As they get older they will spend more of their time just lazing about.      They will also need to be kept away from any garden you may have otherwise you won’t have a garden for long.     If it’s green they’ll eat it whether it is good for them or not!!    They will ‘test’ anything that looks good but will not return to it if it tastes bad, but by that time it may be too late (either for the plant or the animal).    They have a liking for the bark of most young eucalypts and some of the smooth barked more mature trees and it is essential you protect any plant-life if you want it to survive.

Most captive animals will come from orphaned or injured road killed adults and if the animal you happen to be taking on is a male he must be castrated at an early age – usually when they attain a weight of around five or six kgs.    THIS IS NOT AN OPTION  - it is a necessity.    There is no plausible reason for you to breed these animals in captivity – there are literally millions of them out there, many of which will end up being bowled over by a truck or the like, providing yet another orphaned joey for someone to handraise.      There are even more, that end up in our restaurants which is a very good reason why we here in South Australia are not allowed to release handraised animals back to the wild.     After all, why provide an easy target for the first ‘roo shooter that comes along.     Also you do not want a full male Western Grey in a confined situation.    They can become very large powerful animals, growing to around 1800mm (6ft) when standing upright and a full male is going to view you in one or two ways – either as a mate or a rival.   Neither situation is very pleasant.    I have known of too many people who have ignored this advice and have suffered the consequences.    Two of these people spent time in hospital.

All our ‘roos are provided with bins of a dry feed, we use a ‘Ridley’ product called ‘Capricorn Goat Meal’, but any of the proprietary dry feeds will be suitable.     There are special formulas for kangaroos which are very good but we have found that our animals turn their noses up at it and we seem to waste more that we use.   This is probably because they were brought up with the goat meal and have got used to it and they don’t like change.     They also get carrots, apples, meadow hay, oaten hay and a daily hand out of bread, which tends to keep them tame and handleable.    We have also given Lucerne hay but it is expensive and wasteful as our animals will not eat the stalks and we end wasting more than we use.    For this reason we now offer Lucerne chaff which is consumed readily.      There is always fresh water on hand somewhere in their enclosure but we vary the location.    This makes the animals look for it and gives them something to do and it also gives us the opportunity to thoroughly clean out water containers rotationally.

In captivity you could expect a lifespan of around twenty to twenty five years.    In the wild the average lifespan for all the large kangaroo species is seven years.

Breeding

They are highly social creatures and live in mobs of considerable numbers and have a well recognised ‘pecking’ order.     There will be an alpha male at the top of the chain who will maintain and defend his harem to the best of his ability against younger males coming up through the ranks.   He will be constantly challenged by these subordinate males until one is big enough and strong enough to take over.

Most female macropods have the ability to have three young simultaneously, all at different stages of development, one in diapause, one pouch young and an at-foot joey.     The major difference between the Western Grey and other macropods is that it does not have the ability for embryonic diapause and will need to mate again before a new infant can be born.    It is also remarkable that the pouch young and the at-foot joey will be suckling milk of different compositions from different teats simultaneously.    This is true of all macropods.      Mating occurs at any time of the year but only with females who are ready to receive the male.    The alpha male will ‘test’ his females to see if they are ready to mate by sniffing her cloaca and tasting her urine.   If she is ready, mating will occur and can be a rough affair with occasional growling and huffing by both partners.   This ‘barking’ in itself is unusual in these animals.   They are normally silent but will emit a gruff barking sound when mating or if in severe pain or panic.     A young will be born 30 days later and will weighs in at about a one gram.    This ‘jellybean’ will then crawl up from its mothers cloaca into the pouch where it will attach itself to a vacant nipple and there it will stay for about the next 42 weeks.     The young will continue to suckle from its mother for a further five or six months.

Defence

Their only real means of defence is to run (or hop if you like) away.    Their biggest killer by far would be by starvation during times of drought closely followed man and his activities.     These animals are ‘harvested’ commercially and an annual quota is set by the government.    This quota is strictly controlled and will vary in line with population surveys.     In some parts of the country it is a necessary evil to control burgeoning populations.  Their only natural enemies would be feral dogs, dingoes, perhaps foxes and surprisingly, Wedge-tailed Eagles.       ‘Wedgies’ are surprisingly adept at dropping on an unsuspecting joey or adolescent animal and sinking its talons into the animals head.       The Wedgie is not strong enough to carry the animal away but will devour it on the spot.

*Footnote.

All the literature I have scoured in presenting this article shows Macropus fuliginosus as the mainland species and Macropus fuliginosus fuliginosus as the Kangaroo Island subspecies.    However, I would question whether this should be the other way round?         I am basing this hypothesis on the fact that the K.I. animal was the first of the species to be recorded by Matthew Flinders in 1802 and the mainland species not documented until very much later (see paragraph above).   Food for thought!

But wait, there’s more…. A question that has often been asked of me, that I always found difficult to quantify is – “What is the difference between a kangaroo and a wallaby?”    Even though most of the larger wallabies are within the same genus as kangaroos, i.e.  Macropus, my stock answer would be “size”.    But then where do you ‘draw the line’ so to speak.      So, whilst researching this article I came across a note that said the old method for determining the difference was based on the foot size of an adult animal.    If the foot measurement, from the heel to the centre toe, excluding the claw, was more than 250mm then the animal was considered a kangaroo, if less it was a wallaby.    It is also interesting to note that in some places ‘wallabies’ are still called kangaroos e.g. the Red Necked (or Bennetts) wallaby in Tasmania is still, to this day, referred to as the “Brush Kangaroo”.

References

Strahan, Ronald (1983) edited by “The Complete Book of Australian Mammals” published by Angus & Robertson.

Cayley, Neville (1987) “What Animal is That” published by Angus & Robertson

Serventy, Vincent, Editor & Author; Raymond, Robert, Co-editor & Author, (unknown date) “Australia’s Wildlife Heritage”  Published by Paul Hamlyn Pty. Ltd.  Volume 2 pp 591

Kirsch, J. A. W. and Poole, W. E. (1972). Taxonomy and distribution of the grey kangaroos, Macropus giganteus (Shaw) and Macropus fuliginosus (Desmarest), and their subspecies (Marsupalia: Macropodidae). Australian Journal of Zoology 20, 315-39.

(Copyright remains with the author)