The moths have made two trees in People's Park their homes
Parks and gardens workers in Jersey have begun work to destroy two nests of moths which are harmful to humans.
Touching oak processionary moths have set up home in two oak trees in People's Park, St Helier.
But contact with the insects can cause itching, rashes, conjunctivitis and, in some cases, breathing problems.
The caterpillars, named after their habit of forming nose-to-tail processions on the trees, feed on leaves and produce silken nests.
Dr Susan Turnbull, Deputy Medical Officer of Health, said: "The caterpillar of the oak processionary moth poses a risk to human health.
"This is because it has tiny sharp barbed hairs which contain a toxin that can cause irritation and allergic reactions in people. Animals can be affected too.
"I welcome the action being taken led by the Environment Department to deal effectively with the problem that has been identified in St Helier."
Anyone with a severe reaction, or who is uncertain what has caused their rash, should consult their GP.