Thursday, 5 March 2015

Where does my new kitten go?

Firstly - some advertising: If you live in South Australia and would like to know where your cat goes - think about applying to be part of this project This is project run by the University of South Australia in collaboration with Your Wildlife in the US who are also running a cat tracking program - if my US based readers would like to play, follow the Your Wildlife link. 

So new kitten Bento is about 21 weeks old.  He was adopted from the Second Chance Animal Rescue by us in late December.  He was kept inside until he received his full set of vaccinates for both F3 and FIV.  Well, when I say kept inside, I mean occasionally allowed out to play in the back yard in a supervised fashion.  We are also attempting to leash train him, its working so far. Bento is an extremely social kitten, he seems to have no fear and will play with everyone, even small children. Here he is with our friend Nikki playing in the backyard at a BBQ we had in January

Of course, keeping him locked in didn't stop him from trying to escape to the exciting world of outdoors.

So the big day came, fully vaccinated kitten was strapped to his GPS harness and the cat flap was unlocked.  It took numpty kitten nearly a week to figure out how to use the cat flap.... Maybe not the brightest little kitten.

Anyway - by the age of 20 weeks he has figured out how to use the cat flap and spend the last week with access to the outside world while we are at work.  Bento is an extremely social kitten and clearly misses us when we are not home judging by the attention he demands when we are home.  It's also obvious that when we are home he tends to stay inside. 

The GPS data for the first week also tells us that he hasn't left the property yet, or if he has, it is only as far as the neighbours over the road. It also continues to tell us how inaccurate the GPS unit is.  We've looked at the data, we have filtered the data for both HDOP (horizontal dilution of precision) and also for number of satellites. Even doing this, there are some outlying points on the map that can't be accurate.  We'd already figured out by looking at the overnight data from Corsair when she was locked inside, that once the bad data is filtered out, the unit still has a margin of error of about 50m.  If we assume the same margin of error.  We can infer that Bento hasn't left our property yet.

We are playing a bit more with the data and I promise the next post will have maps, I've compensated for the lack of maps with more kitten photos. Everyone likes kitten photos!

It will be fascinating to track how that changes as he gets older, bigger and braver.

After all while one can hunt leaves and crickets in the garden, when inside a kitten can mess up a basket of clean laundry.

Get pats and sleep in laps.

And 'help' write blog posts...

Wednesday, 25 February 2015

Reviving Map My Cat!

So Corsair broke the GPS and we stopped collecting data for awhile, given we'd answered our primary question of does Corsair have a different home.

But we have recently aquired two new GPS's and a new kitten - so its time to revive the experiment.

Unfortunately we lost our beloved Jumble cat to cancer at the end of last year.  He is very missed.

However, a lovely new tiny black kitten made his way into our hearts and lives, his name is Bento, he is a black domestic short hair who is currently about 20 weeks old.

We also recently watched the BBC documentary, the Secret Life of Cats, where GPS trackers were put on 50 cats in a village and their movement tracked and analysed.  We were interested to note that the conclusions largely matched the conclusions that we had made with our sample of three cats.

The information we didn't have, was do the cats share space outside or go there separate ways.  So we have purchased two new GPS trackers with the goal of answering a couple of questions.

One has been placed on Magellan. Magellan is not impressed with the new kitten so has been staying away more often.  Where is he going?

We also intent to put the new unit on Corsair and time match the data from both cats.

The second has been placed on Bento. With the goal of finding out how far does the new kitten wander while he is young and still learning the outside world.

Here is a photo of Bento testing his GPS harness.

Wednesday, 5 February 2014

Jumble, Corsair and Magellan... Oh My!

So, I've left this idle for a while, its probably about time I got back to it.

We've got some data collected from all three cats and today we are going to compare the data.

This data has been utilised to produce heat maps to show where the cats spend most of their time. These maps utilise all the data we have collected from the cats over a period of months, divided by cat.  Each cat was equipped with the GPS for an equivilent amount of time to gather the data. All data has been corrected for HDOP and the innacurate points have been filtered  out.

Jumble's data was collected over a period between 18th April and 10th of May 2013.
Magellan's data was collected between the 10th and 18th of April 2013.
Corsair's data was collected over a period between  22nd April and 8th August 2013. So yes, we do have more data for Corsair than the other cats.

This data was collected over late autumn and winter.  We are now working on collecting data over summer. It will be interesting to note whether there is a seasonal difference.

Jumble is the oldest of the cats. He is a 14 year old, desexed male cat.  He has some health problems. For the last couple of years he has had a recurrent problem with pancreatitis - an inflamation of the belly. When it flares up he gets sick, but we can treat the issue with cortizone. As with most older cats, he is a bit fat, he doesn't move as fast as he used to and he also obviously has some pain as he doesn't leap as high or as confidently as he used to. Jumble spends most of his time asleep on our property. He doesn't wander as far as the younger cats. When I'm home I notice that he spends most of his time asleep either on our bed, our couches, his box, in the back yard. The data gathered suggests that this is his pattern when we are not home as well. Jumble always comes when called, so he is probably never far away. Mapping shows that he never travels more than 120 metres from our home and rarely goes more than 50m from our home.

Magellan is a 3 year old, desexed male cat. Magellan was hit by a car when he was younger but physically appears to have made a full recovery. He certainly still gets on the roof and jumps heights the other cats don't. He is a fairly standoffish cat, not a very friendly and sociable cat. Sometimes he will deign to sit on my desk and watch me type, but rarely comes up for pats or snuggles. He is even more anti-social when friends come visiting and runs from strangers. He appears to be our most active of cats, always the first out the cat flap when it is unlocked in the morning. He is the cat that defends the back yard from the incursions of other cats and he is our little explorer kitty. The data says that Magellan travels further than Jumble but not as far as Corsair. Magellan spends by far and away most of his time on our property. He travels up to 150 metres from our house, but rarely travels outside of our immediate neighbours. He does travel to the neighbours over the road, as does Corsair, but spends less time over the road than she does.

Now Corsair is a three year old female, desexed cat. She is friendly and sociable and loves hugs. She will approach anyone, friend or stranger for pats. She invites random stray cats inside and shows them the food bowl. I've never seen her chase any cat out of the back yard.  She roams further than any of the other cats, up to 200m in every direction from our house. Our house however does remain the focal point of her activities. Its interesting that house B (See Does Corsair have a second home?) is also a focal point of her activities, but she still spends at least twice as much time at our house as she does at house B. Why does Corsair wander further than the other cats? Is it her sex? Is it the search for food to fill her fatty belly? Is it her inate socialness that makes her seek out company when we are not home? These are questions the data won't tell us.

I've overlaid all three cat's data on each other, just to provide a visual representation of how far they travel compared to each other.

As you can see its Jumble being the most homebody, followed by Magellan and Corsair as the biggest explorer of them all.  Breaking down the data into smaller and larger time periods doesn't seem to change the result.

Why do you think Corsair travels so far compared to the other cats? 

Is she in search of adventure? 

Is she is search of food to fill her fatty belly?

Or is she simply searching for hugs and attention?

Sunday, 15 September 2013

Where is Corsair?

Corsair is a troublesome kitten. She likes to pick flowers and leave them on our floor, she likes to get into things she shouldn't. Just the other day she managed to get locked in our car. She had obviously jumped in while Nigel was unloading groceries and then when I got in the car two hours later, she was curled up sleeping in the back seat, not at all fussed about being trapped in the car.

But I am worried about Corsair today, she hasn't come home since Saturday morning and so we worry.

Now cats are cats, she will most likely saunter in completely unconcerned right when we have given up hope of seeing her again, or more likely at 3am, wet and hungry and demanding food and hugs.

She has a collar with a phone number tag on, and she is microchipped, so I like to think that if something happened we would get a call.

Also - we have all this handy GPS data, months worth now (yes, I know its ages since I made a post).  So we know how far she is traveling and where she is hanging out.  We know she isn't going more than about 200m in any direction, so we are concentrating our search efforts within that radius.

It's also been suggested that we do a letterbox drop, asking people to check their garages for trapped cats. Rather than spamming the entire neighbourhood, we will look at the data and just leave notes in the letterboxes of properties that we can see she is going into or near.

Technology - ain't it grand.

Personally - I just want her to come home safe and sound.

Edit: After three nights away Corsair came home. Unfortunately she wasn't wearing the GPS when she disapeared so we dont know where she went.

Saturday, 11 May 2013

Does Jumble really sleep all day?

Does Jumble really sleep all day?

Jumble is our 13 year old cat.

He has been with me since I adopted him as a tiny kitten. A friend who is a vet was told to euthanaise Jumble as a kitten as he was considered to feral to be rehomable. Vet friend knew I was in the market for a ginger kitty, she introduced me to Jumble. The non ginger feral biting kitten who couldn't be rehomed, immediately curled up in my lap and started purring. It was love at first sight, and very little has changed since. Jumble's favourite place is still curled up in my lap, or curled up in our bed, or sitting on top of the laptop or knitting that he percieves is taking up his rightful lap space.

For the last couple of weeks the GPS blogger has been attached to Jumble.  We've got a couple of weeks worth of data from each cat now and so far all we have really determined is that GPS loggers have a fairly big margin of error. We have also established that Corsair roams a little bit further than Magellan and may have a second home. None of the cats roam more than about 150m from our house.

Now, observed data tells us that Jumble spends most of his time sleeping. On the couch, on the bed, in the hammock, outside in the sun in the backyard. And this time of year, once we come home from work, he follows us inside and sits expectantly on the heater vent looking at us until we turn on the heating. Then once someone sits down he will select a lap, usually walking over everyone else in the process. He is secure in his role as dominant cat in the household.

So where is he going when we are not home?

The answer is, not far at all. These maps show two weeks worth of data. If we look at just the green dots, those that are considered to be the most accurate data, it appears he is travelling no further than 50m from our property on average. The focus of his activity is our home.

He spends vastly more time in our property compared to anywhere else. The yellow properties represent 1 to 15 points recorded. The red properties shows between 223 and 1296 points recorded, the only two red properties are our immediate neighbours to the north and south. Our property shows over 1200 points recorded. Jumble has no other home and is perfectly content living in his home with his humans and 'helping' code.

We also looked at the time stamps on Jumble's data, does he do anything particular at certain times of the day? Are there noticable patterns, like there are with Corsair's data?

This map really shows us two things.
One - the GPS logger is innacurate, because Jumble sleeps on our bed all night, or he has a secret cat door to the outside world.
Two - Jumble does most of his roaming in the middle of the day and in the early afternoon. When his humans are home, Jumble likes to be home too.

It's getting on towards winter, the days are getting shorter, the weather colder and we've noticed all three cats have a tendancy to be home when we get home from work. This is not the case in summer when it doesn't get dark til later. Cats like houses with heating. Its also possible that the Do Not Feed tags that were attached a couple of months ago are working, as they are also coming home hungry... 

So internet - what questions would you like answered next?
Its probably about time we did some comparable statistical analysis on our data sets...

Or maybe I should just post more cat photos :)

Saturday, 27 April 2013

Does Corsair enjoy our company?

We work full time and as such, the cats spend most of their time without us at home. And of course when we do come home, we lock them inside for the night, so they are stuck with us all night, despite the pitiful banging on the locked cat door.  Which raises the question, do the cats spend more time at home when their humans are home?

Do they really all sleep on our bed all day, or did someone just forget to turn off the electric blanket?

It is a Sunday, this morning we attached the GPS logger to Jumble.  Jumble is our oldest cat, he is 13. So far despite us gently encouraging him to go out and collect interesting GPS data, he has spent over an hour sitting on me, another hour sitting on Nigel helping him play computer games and a couple of hours sleeping in the sun in the back yard. Magellan is stalking an orange cat in the back yard and Corsair is asleep on the bed.

So we ask the question, are they more likely to stay home if we are home?  We have a couple of housemates who provide ancedoctal evidence that says the cats are less likely to hang around the house when we are away on holiday.

So we pulled Corsair's GPS logging data from Saturday. Nigel was home all day Saturday. I was home Saturday afternoon. This data provides an interesting contrast to the three days of Corsair's travel data from last week, presented in the last post. Those three days of data were weekdays. Nigel came home in the evenings and I was out doing fieldwork so didn't come home at all for two of them.

The data shows that on Saturday morning Corsair got up, wandered over to House B at around 8am, probably for breakfast, then came home and spent pretty much the entire day at our house.I left the house at about 7am for an early morning bike ride. One of our housemates fed the cats and unlocked the cat flap as she left for work at about 7:30am. Nigel, with the house to himself enjoyed a leisurely sleep in and got out of bed around mid morning. Co-incidently, around the same time Corsair came home from her morning wanderings.

Ths map shows how many points we recorded within each property on Saturday. The vast number of points were recorded in our house with 265 points. The second most number of points were our immediate neighbours, with 116 and 58 points respectively.  House B only recorded 23 points and House B's southern neighbour recorded 47 points.  She also appears to have wandered through less properties on the weekend, 24 as opposed to 30+ and she spent more time on our side of the street.

We should also point out that the GPS logger cost all of $50, its a cheap device and there is every possibility that even with us filtering out the bad data, the good data is probably only accurate to within 10m and the OK data is probably only accurate to within 20m. So some of those points in our immediate neighbours properties are probably innaccurate and the cats are actually within our garden. We have to acknowledge the potential margin of error.

The map below illustrates the margin of error problem quite clearly. The data is time stamped and colour coded accordingly: 0 stands for midnight, 1 = 1am, 2 = 2am etc. Corsair was locked inside between 8pm and 7am and asleep on our bed for most of that. Yet the map shows points being recorded up to three houses away.  Which shows that even with the data being filtered for horizontal dilution of precision the GPS is still fairly innacurate.  That or Corsair has super escapey powers and there is a secret cat door that we are unaware of.  This map does clearly show that Corsair wandered over to House B in the early morning and that once Nigel got out of bed, the focus of activity was our house.  At 3pm the batteries on the GPS ran out :)

Now you can get GPS's with sub-centimetre accuracy. The GPS units we use in the field doing archaeology look something like this. A large ruggardised tablet sized device attached to a 2m aerial. Not really something you can attach to a cat. Also these units cost thousands of dollars.

So does any of this tell us if our cats really love us? Or does it just point out the limitations of GPS?  Do our cats really appreciate our company?  I notice that on days when I work from home, they are more likely to spend time inside. When I used to work from home full time, I certainly had company all day, even if only one cat at a time. I know Magellan has sat on my desk and watched me type most of this post. I know that when I came home from my bike ride yesterday afternoon I found Jumble and Nigel napping in the hammock.

 I don't know what you think, but that looks like love to me.

Friday, 26 April 2013

Does Corsair have a second home?

So our initial research question was 'does Corsair have a second home'. Our early GPS logging experiments showed that it looked like yes, she was appearing to spend quite a bit of time at a house across the street. But then we began to question the quality of our data. The last couple of posts detail the methods we have used to refine our data and determine good data versus bad data.

So having solved the data issue, we attached the GPS logger back to Corsair and sent her out to collect some interesting data.

Corsair can be a very appealing kitten, would you feed her if she showed up on your door step and looked at you with big eyes?

It's also worth noting that in an attempt to discourage people from feeding her, we have attached little tags to all the cats collars saying 'Do Not Feed'.  This actually does appear to be working as she now reliably comes home hungry for dinner, which she wasn't before. Either that or the white plastic blinking box attached to her collar is scaring people.

So we have taken three days worth of data and plotted it on a map. We've stripped out the 'bad' data and only presented the good data on this map.

So you can see that like Magellan, Corsair is really only wandering less than 200m from our house. However, unlike Magellan, there are two focal points of activity. One based around our house and one based around the house of a neighbour who lives a block over.

So we refined the data a bit more, trying to determine roughly how much time she was spending in other locations. The map presented below shows how many points occur within each property boundary. We've looked at how many points for each property and colour coded them according to how many points have been recorded in that area. Corsair is wandering through at least 33 different properties. There are two properties with over 284 recorded points. Those are our house (House A) and a neighbouring house a block over (We will call that House B). The houses adjacent House A and House B have the next highest number of points recorded in them. Interestingly she does seem to be spending more time in the block over the road, rather than within our block. She does seem to spend approximately the same amount of time at both our house and House B, with 416 points being recorded within our property boundaries and 417 points recorded in House B. This suggests its probably about time to go knock on the door of House B, or at least leave a polite note in the letter box.

I know the neighbours immediately to the south of us have cats, the neighbours immediately to the north of us do not have cats.  Our neighbourhood demographic is largely older Italian people and younger Middle Eastern (muslim) families.

Our neighbourhood seems to have quite a few cats, but no dogs, or at least I don't hear dogs barking, or see people walking dogs. I do see quite a few cats, usually those being chased out of our back yard by Magellan or Jumble.  Corsair on the other hand smiles at the other cats, makes friends, invites them in the back door and shows them the location of the food bowl.  She is a caring sharing type and looking at the size of her ginormous belly, I suspect a bunch of the cats reciprocate.

That said, we also suspect that our cats have 'infrared vision'. We turned on the ducted heating for the first time this year as the weather is getting colder. Within five minutes, all three cats were inside sitting on the heating vents. Maybe they will spend more time at home in winter.

Above is a photo of a Corsair in her natural habitat.

We don't have night time data for Corsair, she has been reliably coming home for dinner and getting locked inside. Although she has not yet learned that banging on the cat door at night won't make it open. Her preferred sleeping position is at the foot of our bed.

So next week - it's probably about time Jumble got to wear the GPS logger.

So my dear readers, are there any questions about our experiments you would like answered? If we can answer them with the data we have we are happy to try.