From the Hedgehog Street campaign :
It looks as though spring is finally arriving in southern England, whilst other parts of the UK still have deep snow on the ground. This prolonged cold spell will have kept hibernating hedgehogs in their nests, relying on fat reserves to see them through. Supplementary feeding could prove critical for many individuals once they are out and about.
We can already see something of how the weather has delayed emergence, with three times fewer sightings in March compared with the same period in 2012. That's even with a larger team of recorders on the lookout. The BTO's Garden BirdWatch volunteers have detected a similar pattern with hedgehogs in their gardens.