Brown-tail moth caterpillars at L’Ancresse

The hairy black caterpillars, with red and white markings, are covered with hairs which can cause irritation and breathing difficulties.

Jamie Hooper, from Environment Guernsey, would ordinarily manage the common on behalf of the Vale Commons Council.

However, as this is not considered essential work, he has been keeping away and following advice to stay at home.

He said he understood that there were not huge numbers of the caterpillars this year.

But they would be visible around the common for the next few months.

Mr Hooper said the caterpillars spent the winter in silky nets.

‘With this warm weather, they have become more active,’ he said.

‘They will become moths in mid-summer.’

While the caterpillars can cause some problems, Mr Hooper said the creatures often reproduced in cycles, with large numbers some years and few in others.

If humans interfered with these cycles, then it could see a moderate number every year.

‘The signs at this early stage are promising that we won’t have to go out of our way to deal with them,’ he said.

The lockdown also means that the normal maintenance of the common will not be taking place.

Mr Hooper said this should not cause too many problems in the short-term.

‘The growing season is not in full swing yet,’ he said.

‘May and June are the important months. If we can work late April and through May, then we should be fine. But if we lose May, things will look a bit overgrown.’

Agriculture, Countryside & Land Management Services is looking into the caterpillar issue and may issue a statement this week.