I had to give this quite considerable thought. I expected the choices to be easier than they were. Anyway, here's my kit:
One camera:
I wanted to take my K10D-clone Samsung GX-10, as it's my favourite camera to use, and I love the way the CCD sensor records light... but I have to think practically, so it's going to be my K-3II. It'll handle low light better, and the GPS may come in handy for more than photography!
One lens:
This is really difficult. I want to be able to take wide angle shots of the beautiful, curving beaches, but I don't want to miss out on photographing the plentiful wildlife! And something with reasonable close-focusing capability would be handy, for shots of the smaller bugs and critters... It pains me to do this, but I'm going to have to choose my Sigma 18-300 super-zoom. It's the biggest compromise optically of all my lenses (obviously), and needs stopping down for best results - so good light is a must, or else a tripod. But stopped down it's actually very decent (even at the long end). I can live with it optically for the flexibility it'll offer.
One accessory:
A decent, light-weight carbon fibre tripod and ball head. I'll need this for longer exposures, and they'll be quite common with that slow super-zoom lens, I think
One piece of post-processing software:
Darktable 2.4.4 - it's missing the library management capabilities of Lightroom, so I'd have to manage files through folders and naming, but I prefer Darktable's processing features. In any case, I heard in advance that the island's PC might be running Linux
One photography-related book:
I'm so tempted to cheat here and say I'd take my Kindle eReader, but that's not really playing by the rules, is it?!
So, I guess I'll take one of the Magnum yearbooks. There's plenty of variety, and usually quite a lot of people photos, which might offer some company on those rare occasions where I'm feeling just a bit too isolated. But I'll also write something of my own while I'm stranded - a diary, perhaps, with specific sections on my photographic work
One photography-related luxury item:
I'm choosing more software... GIMP 2.8 and a handful of plug-ins (is that cheating?
), including G'MIC with Pat David's excellent film emulations. If I can't have the plug-ins, I'll reluctantly take GIMP on its own