Cleo, a Ministry for Primary Industries detector beagle, pinpointed the envelope containing the petals while scanning the letter trays at the International Mail Centre in Auckland last month.

"She stuck her nose right on the letter. Her tail started wagging like crazy and she responded perfectly, so we definitely knew there was something in there," says Craig Hughes, MPI Manager North, Passenger and Mail.

The envelope revealed a love letter from Australia and some scarlet rose petals.

"We had to remove the petals, as New Zealand's strict import rules forbid fresh roses from entering the country due to the high risk of the material harbouring plant diseases or hitchhiking insects,” he adds. “We didn't want the intended recipient to miss out on this romantic gesture, so we sent a photo of the petals, and a letter outlining the importer's options, namely having the flowers sent back to the sender, treated, or destroyed."

Hughes says MPI detector dogs occasionally intercept fresh rose petals, especially around Valentine's Day, but they are not an everyday find. "The dogs are great at picking them up because they can be difficult to find with x-ray scanning."

Cleo and her handler have been working for MPI since February. They have made nearly 150 interceptions of biosecurity risk goods at Auckland airport and the international mail centre.

Two-year-old Cleo is a product of MPI's detector dog breeding programme. She is from the C-litter, of which four pups are now working as biosecurity detector dogs.