'Alarming-looking' caterpillar webs in park 'harmless'

White webbing seen covering trees and metal gates in Belle Isle Park, Exeter, has been identified as harmless by local authorities and conservation groups. The webs are created by groups of caterpillars, likely ermine moth species, which feed on the leaves inside these protective silk structures. Despite their alarming appearance, the webs pose no risk to public safety or long-term harm to the trees. Butterfly Conservation explained that these caterpillars are voracious feeders and can strip trees and bushes of their leaves, but healthy plants typically recover without permanent damage. The webs serve as a defense mechanism, shielding the caterpillars from predators while they feed in large groups. Exeter City Council reassured the public that the infestation is a natural occurrence and that the caterpillar populations are usually kept in check by natural predators. Experts from the Devon Biodiversity Records Centre noted that it is common to see such webs during this time of year, although it is unusual for them to spread over metal gates and other nearby objects. Multiple species of ermine moth caterpillars, including orchard ermine and bird-cherry ermine, are known to create these communal webs. The extensive silk coverings are a survival strategy, providing safety in numbers despite making the caterpillars more visible. This phenomenon highlights the complex interactions within urban ecosystems, where natural cycles of insect feeding and plant recovery continue even in city parks. While the sight of ghostly webs may cause concern, experts emphasize that these caterpillars play a role in biodiversity and that affected trees generally rebound once the caterpillars have moved on or been controlled by predators.