"We know only too well that what we can't pick up washes into the sea," they added.
They also pointed to the extraordinary success of the 'return and earn' scheme in New South Wales. In less than a year the recycling of drink containers there had increased by 69 per cent, while drink container litter had fallen 44 per cent by volume.
Earlier this month, after another major roadside rubbish collection effort, volunteer Jane Banfield said the amount of recyclable waste discarded along Far North roads represented a powerful argument for a return to bottle deposits. If consumers had to pay a refundable 20 cent deposit on all bottles and cans, she said, they wouldn't throw them out of car windows in the first first place, or they would be picked up by fundraising groups, which could make good money by cleaning up roadsides.
Last month Ms Sage said a discussion document on new regulations for packaging, including container deposits, was "a few months away," while she has also been quoted as saying that the government had no plans to introduce a deposit scheme.
A return to container deposits, common overseas but scrapped in New Zealand in the 1980s, has been strongly opposed by the beverage industry.
According to a 2015 report by environmental consultancy firm Envision NZ, New Zealanders throw away about 46,000 tonnes of recyclable drink containers, enough to fill 700 jumbo jets, every year.
"On behalf of the Bay of Islands' natural world, and our children's future, we beg you, our elected minister, not to delay any longer and to bring in deposit refund on bottles and cans before this year ends," the Paihia volunteers wrote.