Phillip Cullen, 57, was given a suspended six-month prison sentence today for trapping the globally endangered Large Blues.
Bristol magistrates were told at an earlier hearing that Cullen was spotted scrambling over a locked gate near Cirencester, Gloucs.
He was chasing a Large Blue and swiping at it with a net before leaving with a plastic bag.
Phillip Cullen was given a suspended six-month prison sentence
Cullen was chasing a Large Blue
The offences were committed in the knowledge you were capturing and killing an endangered species and the risk of that butterfly becoming extinct in this country
Magistrate Susan Helfer
The next day conservation volunteers near Street, in Somerset, saw him again with his net.
Police later raided his home in Warmley, near Bristol, and found two dead Large Blues among 30 trays of mounted butterflies.
The unemployed former weightlifter denied catching them, saying he had bought them from a dealer in France.
Police found two dead Large Blues among 30 trays of mounted butterflie
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But they were labelled “DB” and “CH”, the initials of the two sites where he had been seen.
Cullen was found guilty of six breaches of the Conservation of Habitats and Species Regulations 2010.
Sentencing Cullen, magistrate Susan Helfer said: “The offences were committed in the knowledge you were capturing and killing an endangered species and the risk of that butterfly becoming extinct in this country.”
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Cullen must perform 250 hours of community service work
Cullen must also perform 250 hours of community service work and his butterfly display cases will be forfeited and donated to a wildlife museum.
The Large Blue became extinct in Britain in 1979, but has since been reintroduced.