The Venomous Snakes Of Hawaii

Every year, millions of tourists travel to Hawaii to enjoy the Aloha state’s sunny beaches, tropical landscape, laidback hospitality, and many attractions. The archipelago, which consists of 8 major islands, is a big hit with visitors but not as popular among certain reptiles. Despite its balmy climate, Hawaii has no native snake species, and the government has strict regulations to prevent their introduction. This is because island ecosystems are fragile, and the introduction of new species can have a cascading effect on the lives of other species of plants and animals. It is illegal to transport or own a snake in Hawaii unless it is for research purposes.

Don’t relax just yet, however. Just because there are no native species doesn’t mean the islands of Hawaii are entirely snake-free. There are two venomous species — one a non-terrestrial snake, meaning it lives in the sea, and an invasive species that occasionally makes its way to the islands from Guam. It’s unlikely you’ll meet either of these reptilian residents during your Hawaii vacation, but just in case, it’s helpful to know their behavior and habitats so you can enjoy your island getaway without worry.

Yellow-Bellied Sea Snake

You may not have heard of it, but the Yellow-Bellied Sea Snake is the most widespread snake species on earth. Also known as Pelamis platurus, this skinny serpent, which ranges from 0.6 to 1.2 m long, packs a venomous bite but is typically found out in the open water, so it’s unlikely you’ll encounter one on a Hawaiian beach. Although they may be blown close to shore, these snakes prefer to hang out in the tropical and subtropical Indian and Pacific Oceans, riding the currents and feeding on fish.

The Yellow-Bellied Sea Snake’s unusual anatomy allows it to thrive in this watery habitat. It has nostrils high on its head so it can breathe while swimming or resting at the surface. The snake also has a tapered body and flattened tail that acts like a rudder to help it stay afloat and change direction while navigating the currents. The sea snake can dive up to 50 feet below the surface and can spend up to 90 minutes underwater. Unlike human divers, the snake is protected from the bends thanks to its ability to release nitrogen through its skin as it ascends back up to the surface.

Yellow-bellied sea Snakes spend their lives at sea — breeding, birthing, and feeding on the open water. They are stealthy hunters, slowly stalking the mullet, jacks, damselfish, mahi mahi, and anchovies that make up their preferred diet. The snakes use their venom to immobilize their prey quickly so they can’t swim away. They have short, non-retractable fangs and release a toxin that attacks the nervous system, paralyzing their victims.

You can easily recognize a Yellow-Bellied Sea Snake from its vibrant yellow and black coloring, which acts as a visual warning to potential predators. The snake also has a distinctive spotted tail. While most encounters with humans are non-deadly — when the snake bites defensively, it typically doesn’t release any venom — their venom can be fatal, causing respiratory, heart, or kidney failure.

Brown Tree Snake

Brown Tree Snakes, Boiga Irregularis, are a highly invasive species that have ravaged ecosystems in Guam, putting Hawaii on high alert for these unwelcome guests. A few have stuck onto the islands in recent years as stowaways in cargo from Guam.

The Brown Tree Snake is mildly venomous, but its bite is seldom more than a painful nuisance for adults. It can cause more severe reactions in children, but bites are very rarely fatal. The snakes are a yellowish to dark brown color with mottled bands across their back. They can grow up to 9 feet long and, as their name suggests, live in trees and dense canopy.

Brown Tree Snakes are nocturnal and feed on birds, small mammals, and reptiles. They have been known to drive bird species to extinction in areas where they have no natural predators, such as Guam.

Staying Safe Around Snakes

Whether you’re on a beach in Hawaii or wandering the mountains of Colorado, local wildlife should be respected and left undisturbed. The same rules apply to snakes. If you see a snake, keep your distance and don’t approach it.

In the unlikely event that you spot a Brown Tree Snake in Hawaii, notify authorities immediately. Don’t attempt to capture the snake yourself. Brown Tree Snakes can be aggressive when threatened and won’t hesitate to bite if they feel they’re under attack.

If you encounter a Yellow-Bellied Sea Snake while enjoying Hawaii’s amazing waters, stay calm. These snakes don’t like confrontation and will likely just swim away if you give them a chance. There were two reported sightings of these snakes in July 2024, both on beaches where the snakes had drifted close to shore, but no one was bitten in these incidents, which are very rare. If you see a sea snake, report it to local authorities as soon as possible.