Fox update 16.04.21
Foxes usually give birth in March or April, their litter size is about 4 or 5 cubs.
Fox cubs at birth are blind and deaf, their nose is relatively short, their ears are small and floppy, and their fur is short and very dark. The vixen’s body heat is needed by the cubs for the first 2 to 3 weeks of life - at least the early part of this period. During that time the male leaves food by the den entrance for the vixen.
After around 4 weeks, the cubs first come above ground, hesitantly initially. By this time, their coat is darkish brown with a reddy tinge to the face, their ears are more like those of adults: longer and erect; and their muzzle has got longer and will continue to do so as adult facial features are developed little by little over the next 4 - 6 weeks. Adult coat colour is also becoming more visible over this period, starting, at least in some animals, at the front and working backwards.
After their first appearance, hunting and foraging instincts quickly kick in as the cubs seek out earthworms and insects to add to a mixture of 'mother's milk' and solid food brought back for them by both the dog fox and vixen. Quite large mammals, such as rabbits, and birds are often provided for the cubs, whilst for themselves, the adults apparently like smaller prey items, such as mice and voles.