Hi nibbler, and welcome to WAB
Firstly, well done for helping your local hog population by supplementary feeding
Could you possibly weigh the smaller hog so we'd be better equipped to advise as to whether intervention is absolutely necessary just yet. As you've already pointed out, 'tis milder down south and still time for hogs to build up the required 600g hibernation weight (especially as they know where to go for a good feed-up
). Ooop here, I still had hedgehogs visiting my garden up until the end of December last year.
As for foxes posing a danger to hedgehogs, I have read reports of very hungry foxes taking young or sick hedgehogs, but I've been feeding foxes and hedgehogs in my garden for as long as I can remember and have never encountered any problems. People's pet dogs are more of a problem to hedgehogs, according to my vet.
EDIT: Our posts crossed Marcia! You obviously type faster than I do!! Double oops! I've just seen your post too Elaine!