Population regulation

[topender]

Does anyone out there in YowieLand have any ideas or theories on what effects the yowie population, most other marsupials and mammals have predators to regulate population, are there envoiromental factors which may influence there numbers?.
Did the Indigeneous groups make a big dent in there population, i would like to hear other peoples ideas.

[folcrom]

Being that Yowies are cryptids and we have little information on them,
any speculation on what regulates their populations would be exactly that,
speculation.

Although, there are some obvious population regulators we could consider.
Availability of food.
Availability of water.
Period of Gestation
(speculative - perhaps similar to human, ie 9 months)
Number of offspring at each birthing
(speculative - perhaps similar to human, one offspring with possibility of more)
Do they have a breeding cycle?
(A great unknown, are they similar to humans, or do they "come on heat" like animals)
The fecundity of any species is important in estimating it's population.
Yowies may not breed very often, this would limit their numbers somewhat.
What is the ratio of Males to Females? (an important factor)
What is their social interaction between genders? (another important factor)
Do Male yowis compete over Females? (another important factor)
What is the survival rate of offspring?
What diseases are indemic in their population?
Do they have "religious" taboos or prohibitions? (very speculative)

Known predators (probably none, except humans).
I remember reading somewhere, that before European settlement,
the Aboriginals dealt with the Yowies in two ways.
One was to stay out of their territory and keep well clear of them.
The other, when the Yowies intruded on Aboriginal territory,
was to hunt them down and kill them.

So the Yowies probably have a long history of distrust when it comes to Humans.
(How they view Europeans as opposed to Aborigines would be interesting)

So we can add the need to remain hidden to their population regulators.
That means the need for large expanses of bush to move around in unseen and
therefore somewhat protected and safe.

Can any-one else think of any others?

Folcrom.

[topender]

thankyou for that, i find i guess like many people that there are more questions than answers, especially when you go down the road of attempting to find evidence in a particular area or locations; some of you have been at this for a long time and have collected a lot of information and knowledge, your comments are much appreciated.

[Pixie Byrnes]

Hi Topender and Falcrom, i thought this small detail might be worth a mention, in relation to breeding,
It's a common rule of the thumb for Australias other two largest mammals down the line, the red kangaroo and the dingo to hold off gestation during times of drought ect..
untill they have ideal conditions, thats two completly separate species and yet share the same protective ability, theres no reason why our Australian yowie would not come equipped with a similar instinctive rule...what do you think?

[folcrom]

Definate possibilty.
Evolution may have given them the ability to "put a hold on gestation" during times of drought.
That would mean that gestation length could very from what we might consider normal (ie 9 months),
to significantly longer depending on conditions in their environment.

How long can a Kagaroo's gestation go on hold for?
Does anyone have any idea on that?
Might be better to work with the example of the Dingo, being a mammal and all.

It might give us an idea of how long a Yowies gestation could (hyperthetically) go on hold.

Of course, if drought conditions continue for a prolonged period,
do Yowie female later produce a higher number of "multiple" births?

Something else to consider

Folcrom.

[Pixie Byrnes]

Hay Folcrom,
here's another little tit-bit,
1) Kangaroo: During droughts the male roo will not produce sperm and the females will only allow conception after there has been enough rain that will produce new vegetation.
That can be a long time when you consider the normal gestation on a good wet season is only 9 weeks and she's got another one in the pouch before the first is fully weaned.
2) Dingoes: Breed only once a year.
Irrespective of social status dingo packs will weaken,
during times of drought, so they tend to split up,
after something like that happens and the good season arrives the Alpha female of a pack will seek out pups not from her own and kill them all off ( now if she's left in her own family group and she only breeds once a year between Autum and the start of winter that could be tricky)
This behaviour is believed to be an adaptation to the Australian enviroment that will demand a common reproductive selection strategy.

hope that helps for a deeper dig at this subject....(SMILE)

[banyula]

Hi topender
my thoughts on the topic relate to moon cycles, which all animals react to. most animals in topend/oz are nocturnal but hunt less in the full moon due to being more observable. I am interested to see if there are more sightings in partial moon phases or in full moon phase. If they are omnivores (as assumed) the availability of 'local critters' and their feeding/watering practices would have a great impact on when and where yowies were sighted, I beleive. What are yours/others thoughts on the topic?
banyula

[banyula]

Hi Topender and Falcrom, i thought this small detail might be worth a mention, in relation to breeding,
It's a common rule of the thumb for Australias other two largest mammals down the line, the red kangaroo and the dingo to hold off gestation during times of drought ect..
untill they have ideal conditions, thats two completly separate species and yet share the same protective ability, theres no reason why our Australian yowie would not come equipped with a similar instinctive rule...what do you think?

hi
all macropods and canines have this breeding sincronisation ability and all mammals will not ovulate during harsh times. (thruout the world). the question i consider is if the yowie is adaptive to other external influences which also affect the indigenous species on which they rely on (?) for survival
wot do you think?
banyula

[Pixie Byrnes]

Yes Thanks banyula!
i think if the breeding times can be regulated by such a wide number of mammals well it seems fair to lock that in as a very strong possibility, more then not.

and the concideration you point out, is a very important one thats right,
If the living conditions and food source is not up to scratch or much harder to achieve then times gone, theres no doubt they would suffer,
when problems like these take hold of an animals surroundings we see them try to or modify their diets or move into new locations, but not all,..sadly noted,
we have lost a few due to this have'nt we.
there have been reports of unusualy close contact between yowie and man, Eg: the yowie seemed not in much of a hurry to move away, and particularly in one case,
the yowie was rather disinterested and for the most part, stayed put , i suspect this behaviour could have been a sign the it was in poor health.


....????????...thanks for your bits...now lets get Topender back in here! "Where are ya Top"s"

[topender]

i appreciate the breadth of information supplied to this question, my reasoning was like many others to add extra threads and answers to the questions that plague me at 1130 at night laying awake, and of course to give me little clues as to where,when,how to search for evidence. the gestational thing is interesting, personally i think our hairy friend is somewhere between primate and human and therefore the things that effect ovulation/gestation are limited, BUT as we know stressfull envoiromental factors can and do effect human reproduction..soooo i'm not sure what to think.... I MEAN WHY CAN'T THEY JUST BE DONE WITH IT AND HAVE SIGNS MADE UP THAT SAY " YOWIES LIVE HERE", that way my searching is made much easier.