Council pest controllers have been urged not to use vacuums or poison to remove oak processionary caterpillars as they risk causing environmental damage.

Conservation agency Vogelbescherming Nederland said biological solutions that encourage natural predators such as insects, birds and bats to feed on the caterpillars were more effective.

The agency has published model letters which people can send to their municipality pressing them to fight the spread of the caterpillars by more eco-friendly methods. The larvae of the oak processionary moth are covered in poisonous hairs which, when shed, can cause itching, swelling and breathing difficulties if inhaled.

Vogelbescherming said councils should hold off from mowing roadside verges and cultivate plants such as clover, honeysuckle and dead-nettles to sustain predators.

The municipality of Wapenveld said it had reduced the infestation of oak processionary caterpillars by 85% since adopting biological pest control.