Many thanks, chaps.

I cannot see wrapping and sealing the straps as being a very practical solution - it had occurred to me, but I could imagine the chemicals attacking the plastic wrapping and the adhesive tape, thereby exposing the leather!!

Mink Oil seems to be the way to go, although I've never seen or heard of it here in the UK. It looks like I need to have a word with a saddle-maker a few miles from here.

A word with Howie is also a very good idea, although I dare say that new chemicals being used in the south of England will also have found their way north of the border. Yes, kilt hire companies must be having kilts dry cleaned by the dozen every day. They should know about these things!

Thanks to you all for the suggestions.