An "unwanted organism" in New Zealand is one of the most sought-after exotic pets in Japan, and buyers from the Asian country are making trips here to seek out the best from an underground network of breeders.
Last year, nearly 600 ferrets from New Zealand were exported to Japan, according to figures provided to the Herald by the office of the Japanese Consulate General in Auckland.
New Zealand was the third-largest exporter of ferrets to the country behind the United States and Canada, despite having only one registered ferret exporter.
It is illegal to keep or breed ferrets in New Zealand, except for export - which requires permission from the Department of Conservation under the Wildlife (Farming of Unprotected Wildlife) Regulations 1985.
Southland Ferrets is the only New Zealand farm with a licence to breed the animals for export, but a Japanese wholesale pet buyer who arrived in Auckland this week told the Herald she would rather obtain ferrets from underground breeders in Northland and the Waikato.
"The ferrets that are not commercially bred on a farm are often more used to human touch and are also more tame," said the buyer, speaking on the condition of anonymity.
"What we look for is ferrets that are of show quality, which could fetch more than five times more in price than an ordinary farm ferret."
New Zealand ferrets, also known as "Kiwi Fe Retto" in Japan, are popular because pet lovers believe they are healthier and can live a longer life because they come from a "healthy, clean and green" country, she said.
In Japan, locally bred ferrets retail for about $300, but those imported from New Zealand - bought for about $50 - can fetch up to $1500.
A Tokyo tour company, run by a Japanese woman married to a Kiwi, organises trips to link buyers with breeders and helps with the export arrangements, the buyer said.
The ferrets obtained from underground suppliers are often exported alongside the legally bred ones.
In Japan, ferrets are a popular pet, behind only dogs and cats and ahead of rabbits, and ferret lovers get together regularly for "ferret festivals" where ferret games and races are held, and even ferret fashion shows.
Yukinobu Kigawa, from the Japanese Consulate General office, said most apartments in Japan do not allow residents to keep dogs and cats, but do not restrict them from keeping ferrets or other small animals.
"Ferrets are quiet animals and do not cause a nuisance to neighbours."
Mr Kigawa said there was no need for an import permit to bring a ferret into Japan, just a veterinarian note to certify that New Zealand was free from rabies and that the ferrets were born and kept there since birth.
Martin Dennis of Southland Ferrets said the Japanese had bought ferrets from him since he started the business 17 years ago. Government figures showed 1066 ferrets were exported last year, but the number bought from his farm had fallen.
The Ministry for Primary Industries says, 548 ferrets were exported to Japan, 386 to Belgium, 108 to Hong Kong and 24 to Singapore last year.
But the Japanese authorities' figures showed 596 ferrets were imported from New Zealand.
Ferrets were introduced from Europe in the 1880s to help control the wild rabbit population, but they are also predators which attack native birds, including the kiwi.
NZ ferret exports
108 Hong Kong
1 number of registered exporters
Source: Ministry for Primary Industries, Embassy of Japan in New Zealand.