We want to shine a spotlight on one of the amazing species associated with kauri forests: the kauri snail/pūpū-rangi.
Kauri snails/pūpū-rangi are giant carnivorous land snails endemic to Aotearoa (found nowhere else in the world!). They belong to the genus Paryphanta in the family Rhytididae. There are two species of kauri snail: Paryphanta busbyi and Paryphanta watti.
Once found throughout the upper North Island, due to habitat loss and predation, their range is now restricted to a few areas of Northland and offshore islands. These giants can live over 20 years and their shell can grow to 79 millimeters in width. Due to their chunky size they are heavily predated upon by rats, possums and pigs.
Kauri snails are hermaphroditic and mating can last up to 10 hours, which is usually triggered by rain. The one centimeter long eggs are laid under dead leaves. Once hatched, the hatchling snails spend an unknown amount of time living up trees and shrubs.
The adult kauri snails live in the damp leaf litter of kauri forests and are predators that hunt earthworms and other snails, including cannibalizing smaller individuals of their own species. They ensnare their prey with their long tongue-like radula, covered in rasping teeth, suffocating and crushing their victim while they retreat inside their shell. This is unusual among snails, which are generally herbivores.
Less than one per cent of historic kauri forest remains, and it is under threat from dieback. Kauri dieback threatens not only the trees themselves, but the entire ecosystem of associated plants and animals (such as kauri snails) that they support.
You can help protect kauri snails by following kauri dieback protocols and doing predator control.