www.ukbutterflies.co.uk

I found a Large White caterpillar, last week, 6 feet up a rendered wall and climbing, going away from the nasturtium patch on which it had been feeding. Might it have been looking for a site to pupate? Or could it have been affected by some parasite which caused its behaviour to be altered?

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Finding a nice cosy site under the eaves to spend the winter hidden away as a pupa sounds a reasonable proposition to me.