The roof of Lincoln Cathedral is infested with Death Watch beetles, but work has begun to fix the problem.
The cathedral, which has an annual general maintenance bill of about £1.5million, has sustained large amounts of damage to its roof beams.
Larvae from the beetle dug into the beams, seriously weakening them, and they can live there for up to a decade.
The death watch beetle is so called as some cultures see it as an omen of impending death.
After securing £300,000 in funding, experts have begun cutting away the worst affected beams from the roof of the cathedral and have started treating others with a special pesticide.
Work is expected to take three years and cost around 1 million for repairs in the roof of the cathedral, parts of which date back to the 11th century.
Currently the Cathedral does not have the budget to afford the repairs, and they are launching a second bid for Heritage Lottery funding after the first bid failed.