The corrections

[Rusty2]

Howdy , for those who want to know , I've finished the new chart . This was bugging the living hell outa me because I put so much work into it and to fail over some kilobytes was unexceptable , it had to be corrected .
Here's how it happened .

I went back into the forest just on dark and set up a table with all 4 audio recorders .
I walked about 10 steps at every 2 metres all the way up to 30 metres away from the audio recorders .

Each footstep was measured from all 4 audio recorders which meant 8 measurements and then an average was taken . Each average of each footstep was then added together to arrive at a final average . This was done 15 times for each 2 metre increment .

The new chart has more than 1 BLUE column to indicate the unknown subject at various distances and not an average like before , this is a much more accurate representation of the subject thanks to Slats idea of distance . Also , each column may represent more than one footstep at a particular distance indicating the subject moving towards and away from the audio recorder .

The problem with this chart is that I still can't tell how big anything is . For example , a large subject may be tip toeing around the audio recorder giving me a false reading , or on the other hand a small subject may be walking heavily also giving me a false indication of distance . This will also be the case with stomping subjects .

Another problem is fallen logs , stumps , trees , boulders and heavy foliage partially block the sound from footsteps reaching the audio recorder which results in the subject appearing to leap from 10 to 30 metres in one single step and then back to to 9 metres distance .
The good thing is that the subjects can't hide their impacts and although the measured distance of the subject may not be the precise distance , the impact measurements speak for themselves .

Having measured the subject from video 47 and 4 seperate subjects from video 48 only 1 has turned out to be what is more than likely a wallaby . It's pretty obvious when you see it in the chart .

The new chart contains 3 wallabies at known distances and at known volumes . Ambience is taken into account to measure the distance of the subject however I've yet to find audio which is more than 4% different from the original recording of myself . For example , a subject who appears to be at 13 metres and after adding or subtracting the 4% only makes it's distance at 12.48 or 13.52 metres , so you can see , a small amount of 520 mm cannot be transfered to the chart .

The green columns are wallabies , the orange columns are myself and the blue columns are the unknown subject . The shortest columns are the heaviest impacts .

I understand some may have doubts as to whether this is accurate or legitimate but I can't see anything that I've missed , maybe you can .

https://youtu.be/dr3vNpdSO9k?t=151

The above video has the 1st subject in question and the charts below are named . Judge it for your selves .

https://youtu.be/yjvgBOx8Lic?t=428
The above video starts at the first unknown subject which is more than likely a wallaby .
The names of the pictures have the video times of the subjects .

[Yowie bait]

Looks like youve put a lot of work in there Rusty! Cant comment on your calculations but i can see the difference in the impacts. The signals with a much heavier impact than yours are impressive! Wonder what that could be?

[Jim]

Hi Rusty,

I always enjoy your posts. To say that you're thorough is an understatement. That said, I haven't watched all your videos so you might have covered what I'm about to suggest already.

But I have one theory about the calls you pick up, the territorial displays in particular. The fact that they're coupled with whistling hints that they might possibly be owl calls? I've heard some species of owl make very convincing, even unnerving barking and grunting noises. They will most often call in the hours preceding dawn too.

I'm really familiar with a few owl calls and songs, specifically tawnies, boobooks, sooty owls and powerful owls. But beyond that I can't say with any certainty.

The thing that makes me uncertain of the theory's veracity is the knocking sound that often accompanies your audio recordings. Never heard an owl call at the same time as hearing knocks.

Cheers!

[Rusty2]

Hey YowieBait , it's a much clearer picture when you see it like this .
Yes , I wonder what those impacts could be from ?

Hey Jim , I understand anyones doubt about all this . It would appear , like you said , that some of the time there are woodknocks or footsteps included in the audio also with the barking vocalisations but not always .
If you can find any recording of an owl that sounds like those calls I'd would reluctantly correct myself . My cousin gave me an encyclopedia of australian bird calls , I'll have a look through the owl section . He actually thought those territorial calls were wallabies .

[Rusty2]

The actual video that went with this .
https://www.youtube.com/watch?v=6FidtaU ... e=youtu.be

[Simon M]

The charts are detailed and clearly presented and you seem to have taken a wide array of variables into account. Even if the best you can do is identify what isn't making a particular sound, that's still valuable information.

[Rusty2]

The difference is pretty obvious Simon , the question is , is that them ?
I believe it's more than likely although I've been wrong before .

[Slats]

Hi Rusty
Merry Christmas!
The data certainly paints a clearer picture in my opinion but like you mentioned it's still not 100%. I'm wondering if using the method for obtaining direction/distance you've used before, if size may be able to extrapolated from that. If you have the approximate distance travelled then you could calculate the average step length, compared to your own you should be able to calculate a size estimate by ratios. It would only be an estimate but it could an extra depth to the data.

[Rusty2]

Hey Slats , Merry Christmas to you too !

I can calculate the height from the step lengths alone . But as Trevor has mentioned the biomechanics of the hairy people may be different to us making our estimation of height only a guess based on ourselves .

If we could say that a subject is roughly 6 foot tall then the average 6 foot tall person is around 80 kilograms . But is a 6 foot tall yowie 80 kilo's ? Or , are all 6 foot tall yowies 80 kilograms ? I doubt it .

I'd be much more interested in calculating the weight of the impacts . If I could get a 150 kilo person , a 100 kilo person and a 50 kilo person into the forest to test then we might be able to draw a line in a graph and say with confidence that "this impact is from a 120 kilo subject" , that would be good .

[Slats]

Rusty would it be possible to obtain the results from a single stereo recorder 2 channel or do you need the 4 channels for better accuracy?
I'm asking because if it's possible I could provide extra data for you (I wiegh 132kg). I'm sure other researchers who are interested in the audio side of things may be able to assist aswell an Australia wide citizen scientific collaboration if you like.

[Rusty2]

Hey Slats .
That's not a bad idea . 4 audio recorders would be better for accuracy like you said , so I'm not sure how a single audio recorders results would change or influence the results .

I have 2 charts to work off , a volume chart versus distance and an impact chart versus distance so a weight chart versus distance should work , I can't see why not . You'd have to do a complete new chart which means you'd have to find 3 people with large differences in weight and use the same settings as I'm using in my recordings .

[Slats]

I'll do an experiment to see how one recorder works out, as I only have the one at the moment. I did think about the variables of the different recorders but that can be reduced by the same settings. I'm 132, my wife is around 60 and my two sons are 40 and 30 so there would be enough difference in mass to see a difference in the results.
My only concern would be that the my recorders microphone input is quite low and I can't adjust it prior so I would need to adjust the amplification (get the background noise to match yours in decibels) after to match your results. It should be strong enough data to see any trends.

[ripperton]

Damn ! Audio recording is better than a trail cam hands down.
I just got back from a session up the coast and although I didnt get any Yowies I got audio of a fox eating apples and corn so crisp and clear you can see his little snout and teeth ripping chunks out and chewing. The way you can leave an audio recorder running 24/7 eliminates the problems of motion sensors not working properly. I hid the Sony 412 wrapped in a thin plastic bag and stuffed into a crack in the dirt. The little guy took a good 40 minutes to eat 2 apples and about 5 short cobs of corn. Funny he didnt do much with the roast chicken except sample it.
Something wrong with the Sony though. Left it there overnight (14 hours) but only recorded 1 hour and 50 minutes. Batteries wernt flat and was still recording when I got there in the morning. Must have missed out section in between.
I need an MP3 file editor so I can extract a funny section of the fox burping or farting, making some weird noise.
Went overboard with the chickens this time.

[Slats]

I need an MP3 file editor so I can extract a funny section of the fox burping or farting, making some weird noise.

Hey Ripperton
I use Wavepad on the recommendation of a couple of other researchers. It's free to download for home use and very easy to use.

Cheers

[gregvalentine]

Something wrong with the Sony though. Left it there overnight (14 hours) but only recorded 1 hour and 50 minutes. Batteries wernt flat and was still recording when I got there in the morning. Must have missed out section in between.

Yowies are super clever - they can switch electronic stuff off and on with their mind . . .

[ripperton]

Something wrong with the Sony though. Left it there overnight (14 hours) but only recorded 1 hour and 50 minutes. Batteries wernt flat and was still recording when I got there in the morning. Must have missed out section in between.

Yowies are super clever - they can switch electronic stuff off and on with their mind . . .

I know they can probably fart and burp like a fox too.

[ripperton]

Wave Pad Rocks !!!!!!
heres the burp fart ect.