With orchards being replaced by more productive crops, conservationists aren't sure how many of the beetles still exist, the BBC reported Monday.
Matt Smith, consultant ecologist for The People's Trust for Endangered Species, said the best place to look for the beetle, which is green with a metallic sheen, is in traditional orchards with big old trees during July and August.
Historic records show the beetle was once widespread in England but its habitat has been shrinking for more than a century.
"Hanging on to the old traditional British orchard is the key thing to keeping the noble chafer as a British beetle," said Smith. "They're a flagship species, very photogenic and the public can spot them."
The BBC said anyone who spots a noble chafer should contact the trust at firstname.lastname@example.org.