The unofficial deadline I proposed to my supervisors back in January was 15th March(!). But of course delays and problems along the way have caused this deadline to overrun by a mere 3 months. This of course puts the rest of my thesis in a bit more jeaopardy but I feel like the last few months have been a massive learning curve and have been well worth the endless hair-pulling and 'throwing my computer out of the window' in frustration events. Sort of...
I now feel like I have a decent-ish model of the large scale population dynamics of jaguars. Territories are strongly correlated with population size which is a nice validation that things are working as expected. Territories are also pretty much the size that would be expected, although a little on the small side if truth be told. I have found it incredibly difficult to obtain a true territory-resource relationship so that territory sizes are not imbedded in the code of the model, but rather an emergent feature. I still think more work could be done here and I will continue to develop this further as time goes on and I get some more feedback from a larger variety of people.
Some results from my model are shown below. Population size is reduced within the first 10 years and then stabilises.
Territory sizes of males (blue) and females (red) increases with smaller population sizes.
Territory sizes increase over the first 10-20 years and then stabilise. The decreasing trend correlates with the increasing trend in population size.
A snapshot of the simulation after the first 3 years showing clear territories of individuals (coloured areas - different colours equate to different individuals) - all shown on a habitat map of the area.
A full map of the landscape used can be seen below showing a range of different habitats, the outline of the protected area and the camera traps.
Validation of the model with field data was a bit iffy at first glance. Field data captured 191 jaguar sightings, the model captured an average of 5 per data collected period. But discrepancies are mainly due to the models inability to capture the fine-scale social-oriented movement of individuals. In the real world males are known for making 'information-gathering' expeditions along trails to find out who has been around and when, with sub-adult males known to follow older male for short periods. This has not been included in the model, but its generally thought to be a non-fitness function and not thought to affect territory dynamics or the contact/interactions between individuals.
I can't of course display all the results and discussion from the model outputs just yet as I'm currently trying to update the chapter for submission to a publication. Once its been submitted and reviewed I will then make it openly available!
Open-source information for all.
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