New Zealand's Carnivorous Snails (Powelliphanta)

When you hear of snails you probably do not consider them to be large, able to live up to 20 years, or survive by eating other animals. But this snail is definitely an exception, which makes studying them rather exciting! So let's learn more about what they eat, and where they live.

Image via the Department of Conservation in New Zealand

Physical Description and Behavior

The Powelliphanta are rather large, being on average 9cm (3.5 inches) across. They are even able to grow as much as 15cm (6 inches). Their shells are ornately patterned and can come in a variety of colors and shades, such as brown, yellow, black, and even greenish tints. Due to their large size, they have to live in moist environments because they can't create a mucus layer at the opening of their shell. Without their layer at the opening of their shell, they will dry out like a partially opened package of hummus in the fridge.

Fun fact: These snails are carnivorous. While they consume slugs, their favorite delicacy is earthworms, which they suck into their mouths like spaghetti noodles. They can also live upwards of 20 years as well, which is a long time for many animals, let alone snails. Most land snails only live 1 or 2 years at max.

These are the eggs of a different genus of giant snail in New Zealand, the Pupurangi, but this is how they also should look with this genus as well. Image via the New Zealand Department of Conservation

They are also nocturnal, preferring to travel at night to avoid predators. All of these snails are hermaphrodites, containing both male and female reproductive organs. They can lay 5-10 eggs a year, which are often pink and hard, similar to that of a bird's egg.

Habitat and Location

Information from a 2007 study titled: Taxonomic and conservation status of a newly discovered giant landsnail from Mount Augustus, New Zealand

This genus consists of 16 species and 57 subspecies, of which the vast majority are either endangered or at high risk of extinction. Part of which is due to habitat loss. These snails only live in small areas of moist forest, so the removal of said forests creates massive issues for this genus. In fact, it is illegal in New Zealand to own these snails or even their discarded shells.

Introduced predators in New Zealand are also a major issue. These snails do not have defense mechanisms against predators such as the possum, rats, pigs, and hedgehogs. Some possums have been known to consume as many as 60 snails in a single night, exacerbating the problem.

If you want to see one of these massive snails slurp down an earthworm, check out the video below: