Hawaii does not have any native snake species. While the islands boast a wide variety of native animals and plants, any snake found in Hawaii is considered invasive, as it poses a threat to native species. It is illegal to own pet snakes in Hawaii because of their threat to the islands’ ecosystems. However, the lucrative illegal exotic animal trade sometimes smuggles snakes like pythons or boas past customs. Therefore, any resident in possession of a snake can face up to three years in prison and/or a fine of up to $200,000. Of the various invasive snake species found in Hawaii, only four are large or venomous enough to pose a significant threat to people. Continue reading to learn about the four most dangerous snakes in Hawaii.
4. Yellow-Bellied Sea Snake
Yellow-bellied sea snakes are found in most tropical and sub-tropical waters worldwide, but are virtually absent from the Atlantic Ocean.
©Ken Griffiths/Shutterstock.com
| Size | Measures 10 to 45 inches long and weighs 3.2 to 8.5 ounces. |
| Location | Primarily in open ocean waters, rarely approaching shore. |
| Danger to humans | Its venom is highly toxic and potentially lethal, but no attacks on humans have been reported. |
| Behavior | This species is seldom seen and is highly evasive. |
The yellow-bellied sea snake (Hydrophis platurus) is recognized by its yellow ventral scales and black dorsal scales. The species has a distinctive paddle-shaped tail with light yellow and black spots. It has a thin, narrow body and a small head. As an invasive marine species, it poses a significant threat to Hawaii’s fragile island ecosystems. This snake can outcompete native predators and damage habitats, particularly coral reefs. While the yellow-bellied sea snake is one of the most venomous snakes in the world, it is elusive and seldom seen on shore.
3. Ball Python
Like the boa constrictor, ball pythons are also exotic pets imported illegally to Hawaii.
©Sanne Romijn Fotografie/Shutterstock.com
| Size | Measures 2 to 5 feet long and weighs 3 to 5 pounds on average. |
| Location | Forests, dense tree canopies, or ground cover, usually brought to Hawaii illegally as pets |
| Danger to humans | Minimal danger to humans, but a large threat to the ecosystem in Hawaii |
| Behavior | Non-confrontational and non-aggressive, as most found in Hawaii are lost or abandoned pets. |
Ball pythons (Python regius) come in different color variations and patterns, but are easily identified by their lean bodies and large heads. Ball pythons are typically dark brown or black with light brown blotches on their backs and sides. Like the boa constrictor, most pythons found in Hawaii pose only a mild danger. As constrictors, they lack venom but kill by wrapping their bodies tightly around their prey. In the wild, they prey on a variety of small mammals and birds. According to the IUCN, the ball python is Near Threatened.
2. Brown Tree Snake
The brown tree snake is a threat to both humans and the ecosystem in Hawaii.
©Janelle Lugge/Shutterstock.com
| Size | Measures 3 to 6.6 feet long and weighs 18.43 ounces to 5 pounds. |
| Location | Wooded areas and trees. |
| Danger to humans | Venom is mildly toxic and can cause serious symptoms, especially in children, but it is rarely dangerous to healthy adults. |
| Behavior | Aggressive and known to bite without warning. Devastating to wildlife in Hawaii. |
Brown tree snakes (Boiga irregularis) are recognized by their thin and agile bodies, narrow heads, and catlike eyes. They are light amber colored on the back, with tan or light brown bellies and muted brown spots. This species is highly invasive and has devastated native bird populations in Guam. In 2018, Hawaiian officials imported four brown tree snakes to train dogs on their scent. The dogs were then used to detect brown tree snakes both on the islands and in cargo arriving by plane or boat.
1. Boa Constrictor
These snakes are often lost or abandoned pets or brought into the state by the illegal exotic pet trade.
©Natalia Kuzmina/Shutterstock.com
| Size | Measures 6 to 10 feet long and weighs 22 to 33 pounds on average. |
| Location | Found in trees, dense vegetation, and other locations, depending on the subspecies. |
| Danger to humans | Poses mild danger to humans, but is a significant threat to Hawaii’s ecosystems. |
| Behavior | Nonvenomous, solitary hunters that constrict their prey. |
Boa constrictors (scientific name also Boa constrictor) have heavy and muscular bodies. Their coloring depends on the subspecies, and they have distinctive dark brown or black markings down their sides. Boa constrictors have triangular heads and are nonvenomous. However, their bites are still quite painful. They are large, powerful constrictors that prey on rodents, amphibians, domestic pets, and mammals as large as brocket deer, wild pigs, and monkeys. Because of the variety of available prey and the lack of natural snake predators on the Hawaiian Islands, boas have been able to prey on and outcompete local species. This is especially concerning as many of these native species are already endangered.
