So what has actually been happening with the project since I returned from the Scillies? What even happened on Scillies? Shall the hardships I faced there be forever a secret? Well no actually, I wrote the whole thing down. It’s on the main page!
Various things have been happening since the summer, mainly involving analysis of the GPS and observational data. Look, a map!
It looks rather complicated doesn’t it? The three different colours represent the three different colonies at which birds were caught and tagged.
This map also contains data from the FAME project, taking us to a grand total of…. 12 birds! Yes, it seems like the RSPB had as little luck as we did on some years. Nevetheless twelve birds is still rather a lot of data. So far I’ve divided the tracks into individual foraging trips for each bird using a script in R that I was given by some gannet researchers. As an example, here is a single bird, with each foraging trip represented by a different colour.
What I need to do now is to look at the clustering of the points in order to find out where the birds were actually foraging, rather than flying, and see if there are any common areas. This is going to require me to weight the points depending on clustering, which will require the use of something called First Passage Time Analysis. Once I’ve done this, I’ll be able to ask questions about preferred foraging areas depending on year, colony, individual and so on.
The observational data suggested some interesting trends, which I may focus on in the next field season. I am also currently dabbling with mathematical modelling to help generate predictions for next year.
What is mathematical modelling? Simply put, it’s attempting to create equations which can represent a (hugely simplified version of) the real world. For example, I am interested in how foraging rafts affect diving. So ideally I will create an equation where changing the number of birds in a group will alter the diving (whether this is represented by time underwater or prey caught or some other currency). Of course I’d likely have to add a bunch of other parameters. This could include sea state, recovery time, prey distribution, depth of prey.
This could get complicated and I am most definitely not a mathematician. Watch this space to potentially see a man get driven mad by numbers.