Is the Olive-headed Sea Snake venomous?

Yes. The Olive-headed Sea Snake (Hydrophis major) is venomous and belongs to the Elapidae family (cobra, mamba, coral or sea snake). Its bite is considered high risk to people. Treat any bite as a medical emergency.

Is the Olive-headed Sea Snake poisonous?

Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Olive-headed Sea Snake is venomous, delivering venom through a bite.

Where does the Olive-headed Sea Snake live?

The Olive-headed Sea Snake has verified records in 5 countries, including Australia, New Caledonia, Papua New Guinea. See the distribution section below for its full range.

Elapidae

Olive-headed Sea Snake

Venomous

Hydrophis major

Olive-headed Sea Snake — Hydrophis major, © Steve Llewellyn

6 photographs of the Olive-headed Sea Snake. © Steve Llewellyn.

The Olive-headed Sea Snake (Hydrophis major) is a venomous snake in the Elapidae family, recorded in 5 countries.

If you are bitten

This is a venomous snake. Treat any bite as a medical emergency: stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to emergency care immediately. Do not apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call your local emergency number or poison center.

Family: Elapidae
Danger: high

About the Olive-headed Sea Snake

The olive-headed sea snake (Hydrophis major), also known as the greater sea snake, is a species of venomous sea snake in the family Elapidae.

Geographic range

It is found in the eastern Indian and western central Pacific Ocean in the waters off southern New Guinea, New Caledonia, and Australia (New South Wales, Northern Territory, Queensland, and Western Australia).

Description

Yellowish or pale brownish dorsally, with darker brown or blackish crossbars. Crossbars may be all the same width, or they may be alternately broad and narrow. White ventrally, with or without small dark brown spots.

Adults may attain a total length of 105 cm (3 ft 5+3⁄8 in), with a tail 12 cm (4+3⁄4 in) long.

Dorsal scales imbricate (overlapping), strongly keeled on the neck, weakly keeled on the body; arranged in 31–36 rows around the neck, in 36 to 41 rows at midbody. Ventrals 200–236.

Head moderate. Body stout. Rostral as broad as deep. Nasals shorter than the frontal, more than twice as long as the suture between the prefrontals. Frontal longer than broad, as long as its distance from the end of the snout. One preocular and two postoculars. Two superposed anterior temporals. Seven or eight upper labials, third and fourth entering the eye. Only one pair of small chin shields. Ventrals distinguishable, but very small, either smooth or bicarinate.

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Olive-headed Sea Snake

Is the Olive-headed Sea Snake venomous?: Yes. The Olive-headed Sea Snake (Hydrophis major) is venomous and belongs to the Elapidae family (cobra, mamba, coral or sea snake). Its bite is considered high risk to people. Treat any bite as a medical emergency.
Is the Olive-headed Sea Snake poisonous?: Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Olive-headed Sea Snake is venomous, delivering venom through a bite.
Is the Olive-headed Sea Snake dangerous?: This is a venomous snake. Treat any bite as a medical emergency: stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to emergency care immediately. Do not apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call your local emergency number or poison center.
Where does the Olive-headed Sea Snake live?: The Olive-headed Sea Snake has verified records in 5 countries, including Australia, New Caledonia, Papua New Guinea. See the distribution section below for its full range.

If you are bitten by the Olive-headed Sea Snake

A venomous snakebite is a medical emergency. Call your local emergency number immediately. In the US, dial 911 or Poison Control at 1-800-222-1222.

Get away from the snake and stay calm. Most bites worsen when people panic or try again to handle the snake.
Call 911 or Poison Control (1-800-222-1222) right away. Antivenom works best when given early.
Note the time of the bite and, from a safe distance, the snake's color and pattern, a phone photo is enough. Do not chase it.
Keep the bitten limb still and at roughly heart level. Sit or lie down and limit movement.
Remove rings, watches, and tight clothing near the bite before swelling starts.
Gently wash the bite with soap and water and cover it with a clean, dry dressing.

Do not

Do not cut the wound or try to suck out the venom.
Do not apply a tourniquet or ice.
Do not drink alcohol or caffeine.
Do not take aspirin or ibuprofen, they can worsen bleeding. Acetaminophen is safer for pain.
Do not try to catch or kill the snake. A dead snake can still bite by reflex.

First-aid guidance adapted from the U.S. Centers for Disease Control and Prevention (CDC NIOSH), Venomous Snakes. Educational only; always follow the instructions of emergency responders.

Where it is found

Australia New Caledonia Papua New Guinea Indonesia Thailand

More Elapidae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards: Squamata
FamilyA group of related snakes that share key traits: Elapidae
GenusA close-knit group of very similar species: Hydrophis
SpeciesThis exact snake, named in the two-part scientific name: Hydrophis major

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.