O ne concern is disruption of hedgehogs’ natural behaviour. Hibernation is not the same as sleep. It seems to be a decision along the lines of the Mr Micawber's Cost Benefit Calculation.* In the case of hedgehogs this is based on energy expended for callories gained. As the temperature cools with the onset of winter the abundance of available food declines to a point where its nutritional benefit is outweighed by the effort required to find it. At this point a well-nourished hedgehog hits the sack. A ‘well-nourished’ hurcheon weighs about 1½ lbs or more. A hedgehog weighing less than that may not survive hibernation as it will simply run out of fuel. If found, they need adopting, housing, keeping warm and feeding. See e.g. Hedgehog Street . By feeding them throughout the year am I unwittingly encouraging hedgehogs to remain active when, in the absence of my feeding them, they would hibernate? And if so, what might be the consequences?

H edgehogs of the species Erinaceus europaeus do not invariably hibernate. Those introduced in New Zealand from Britain for example rarely hibernate as food remains sufficiently plentiful during their winters. But I live in Somerset, G.B. Were there to be snow lasting say a fortnight, by no means unheard of although increasingly rare as the climate warms, the hedgehogs that currently visit my garden to feed may not have established a safe and secure place in which to hibernate, let alone made the necessary physiological adjustments. And as Peter's grumpy grandfather (cf. ‘Peter and the Wolf’ ) might ask “what then?” This is a question to which I do not at present have an answer any more than did Peter.

A nother dilemma presented itself in 2022. The number and frequency of hedgehogs visiting my feeder declined markedly from mid June when a rough census, taken by visual recognition of individuals on camera, indicated 6 to 8 individuals on one night. A week later numbers were down to 2 or 3 a night. Throughout July I noted only 2 or 3 individuals a night at best; often there was only one solitary hedgehog and on 3 days there were none recorded - unprecedented at the time. August continued much the same as July; till the 18th there were never more than one or two hedgehogs recorded and on 6 days there were none recorded. This was during a spell of prolonged dry, and latterly, very hot weather. Aestivation is similar behaviour to hibernation but in response to hot, dry conditions. Apparently hedgehogs æstivate in other, hotter countries but they are not Erinaceus europaeus . Aestivation has not been recorded in G.B. Why there was a collapse in the local Somerset population is unclear. Others in the area reported a similar decline so it's not just me.