A pair of swallowtail caterpillars feeding on milk parsley at NWT Alderfen Broad © Ian Davis
Five milk parsley plants and swallowtail butterfly caterpillars were robbed from a nature reserve in Norfolk in mid-July.
The theft occurred at Hickling Broad, a Norfolk Wildlife Trust reserve and well-known site for Britain’s largest native butterfly.
Swallowtails are only found in the wild in the UK at a few sites in the Norfolk Broads.
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An adult swallowtail butterfly at NWT Hickling Broad © David Rounce
“To dig up these rare plants from an internationally important nature reserve and deliberately take rare swallowtail butterfly caterpillars is an appalling wildlife crime,” says Brendan Joyce, chief executive of Norfolk Wildlife Trust.
Milk parsley is a protected plant related to cow parsley with a vulnerable and declining population.
It is found mainly in marshlands in East Anglia, and is the only plant that swallowtail caterpillars will feed on.
A swallowtail caterpillar on milk parsley at NWT Hickling Broad © Rod Horne
“The police are currently investigating the incident and we would urge the public to contact them if they see swallowtail butterflies in an unusual or previously unknown location or if they are approached to purchase any butterflies or plants,” says Joyce.
Under the Wildlife and Countryside Act 1981, it is an offence to uproot plants from the wild without the permission of the landowner.
In addition, it is an offence to uproot or sell European protected species under the Conservation of Habitats and Species Regulation 2010.
Swallowtail butterflies are also fully protected by the Wildlife and Countryside Act 1981.
Click here for more information about the Wildlife and Countryside Act 1981
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Read more wildlife news stories in BBC Wildlife Magazine