New Zealand is renowned for its distinct natural landscapes, from majestic mountains to lush forests and extensive coastlines. Its long isolation has shaped an environment where unique flora and fauna evolved. Many visitors inquire about the presence of certain animals, particularly snakes, given the prevalence of reptiles elsewhere.
The Definitive Answer: Terrestrial and Marine Snakes in New Zealand
New Zealand has no native terrestrial snakes; land-dwelling snakes do not naturally occur or breed on its main islands. However, marine snakes, primarily the yellow-bellied sea snake and various sea kraits, are occasionally found in New Zealand waters or washed ashore. These marine creatures spend their entire lives at sea, typically arriving on ocean currents from warmer tropical waters.
The yellow-bellied sea snake (Pelamis platurus) is the most commonly sighted, with 6 to 10 records annually, mainly around the North Island’s northeast coast. Though highly venomous, these snakes are generally docile and often found unwell due to colder water. Sea kraits, like the yellow-lipped sea krait (Laticauda colubrina), are also occasional visitors. Unlike yellow-bellied sea snakes, kraits come ashore to digest food, bask, and lay eggs, but they do not breed in New Zealand due to cold waters. Any land snakes found are accidental introductions, typically stowaways, and do not represent established populations.
Why New Zealand is Largely Snake-Free
New Zealand’s lack of native terrestrial snakes stems from its ancient geological history and isolation. The landmass, Zealandia, separated from Gondwana 85 to 80 million years ago, before modern snakes diversified. The Tasman Sea, nearly 2,000 kilometers wide, formed an oceanic barrier preventing terrestrial animals, including snakes, from naturally migrating.
This isolation allowed New Zealand’s unique fauna to evolve without snake predators. Native birds, especially flightless species like the kiwi, and reptiles such as the tuatara, developed without this predatory pressure. Consequently, these species lack natural defenses against snakes. The climate and ecological niches are also not ideally suited for most snake species, hindering establishment even if introduced.
Protecting a Unique Environment
New Zealand maintains its snake-free status through strict biosecurity protocols. The Ministry for Primary Industries (MPI) enforces measures at ports and airports to prevent accidental introduction of exotic species, including snakes. These include thorough inspections of cargo, baggage, and vessels. Any live snakes found are immediately removed and humanely euthanized to prevent their establishment.
Established snake populations would severely impact New Zealand’s native wildlife. Many native birds, reptiles, and invertebrates evolved without snake predation and would be highly vulnerable, potentially leading to declines or extinctions. While snakes are absent, visitors sometimes mistake native New Zealand lizards, such as geckos and skinks, or even eels, for snakes. Geckos have velvety skin and broad heads; skinks have smooth, shiny skin and can blink, distinguishing them. The tuatara, an ancient reptile unique to New Zealand, resembles a lizard but belongs to a distinct lineage.