Red-Bellied Black Snake

Pseudechis porphyriacus

Last updated: March 19, 2023
Verified by: AZ Animals Staff
© Ken Griffiths/

These snakes are the only ones in the genus Pseudechis to give birth to live offspring.


Red-Bellied Black Snake Scientific Classification

Scientific Name
Pseudechis porphyriacus

Read our Complete Guide to Classification of Animals.

Red-Bellied Black Snake Conservation Status

Red-Bellied Black Snake Locations

Red-Bellied Black Snake Locations

Red-Bellied Black Snake Facts

Lizards, fish, frogs, and other snakes
Name Of Young
Neonates or snakelets
Fun Fact
These snakes are the only ones in the genus Pseudechis to give birth to live offspring.
Estimated Population Size
Biggest Threat
Feral cats, birds of prey, and humans
Most Distinctive Feature
Its underbelly is several shades of red.
Distinctive Feature
Female red-bellied black snakes have a different hinge mechanism in their jaw from males.
Other Name(s)
Common black snake, red-belly, RBBS, and several indigenous names including "djirrabidi"
Litter Size
5-18 live young
Woodlands, grasslands, forests, swamps and other wetlands, streams, and shallow rivers
Common Name
Red-bellied black snake
Number Of Species

Red-Bellied Black Snake Physical Characteristics

  • Red
  • Black
Skin Type
12 years in captivity, wild unknown
1.4-1.8 m (4.5-6 feet)
Age of Sexual Maturity

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Around 35 people are bitten by these snakes each year, however there have been no recorded fatalities.

The red-bellied black snake is a semi-aquatic, carnivorous species of venomous snake native to Australia. The bite of these snakes is toxic, but they are not considered an aggressive species. Despite their shy nature, they still bite about three dozen people annually, though there aren’t any confirmed deaths. They are one of the most common snakes found in the eastern part of Australia.

5 Amazing Facts About Red-Bellied Black Snakes!

  • Female red-bellied black snakes have a different hinge mechanism in their jaw from males.
  • This species has gone through eight separate scientific names!
  • These snakes give birth to live offspring, around 22.8 cm or 9 inches, rather than laying eggs.
  • The only difference between a juvenile red-bellied black snake and an adult is the size.
  • Indigenous populations referred to these snakes as “djirrabidi.”
A closeup of a Red-Bellied Black Snake flicking its tongue

The hinge mechanism in this snake species’ jaw differs between females and males.

©Paul Looyen/

Scientific Name

Red-bellied black snakes are one of the least venomous of the Elapidae family of snakes. The scientific name for the red-bellied black snake is Pseudechis porphyriacus. This scientific name means “red-purple false viper” in Latin and Greek.

This snake was first described in 1794 and has had several scientific names during that time before receiving its current one. Originally it was known as Coluber porphyriacus because it was incorrectly believed to be non-venomous. The red-bellied black snake over the years has been named Trimeresurus leptocephalus, Naja porphyrica, Acanthophis tortor, and Trimeresurus porphyreus, and a couple of misspellings of its current name. These snakes are also called the common black snake, red-belly, RBBS, and several indigenous names. No subspecies have been confirmed, although some believe there may be at least two potential subspecies.

A coiled Red-Bellied Black Snake flicks its tongue

This species’ scientific name means “red-purple false viper” in Latin and Greek.

©Ken Griffiths/

Evolution and History

There is a possibility that these snakes adapted to their environment in response to the threat of the cane toad. Native to South and Central America, cane toads were introduced to Australia in 1935 in an effort to control beetles that were destroying sugar cane crops but unfortunately these predators with voracious appetites became an invasive species. A study published in 2016 showed that red-bellied black snakes have developed an increased resistance to the toxins of cane toads and a reduced desire to prey on them. This suggests the snake’s behavior and physiology have undergone a rapid evolution, within 23 generations, due to cane toads.

While all other species in the genus Pseudechis lay eggs, red-bellied black snakes give birth to live young. This is beneficial for females living in cooler climate habitats as it gives them more control over the temperature during the reproductive process.


A red-bellied black snake’s size is distinctive, reaching 1.4-1.8 m (4.5-6 feet) in length. The top part of its body is a shiny solid black, while the underbelly is several shades of red. The head of this snake transitions seamlessly into its body, with no distinguishable neck. They are very similar in appearance to a blue-bellied black snake, save for the belly color. Other similar snakes include the Eastern brown snake, Inland taipan, and carpet python.

Red-bellied Black Snake

The red-bellied black snake has no discernible neck.

©Ken Griffiths/


Red-bellied black snakes are timid; in most cases, they would rather slither away than attack a human. The only possible exception is when a female is pregnant and defending her babies. However, they are not an aggressive species and for their size, their venom is comparatively one of the weakest of the elapids.

The venom from a red-bellied black snake bite can cause a lot of issues. It keeps blood from clotting, so the bites bleed a lot. In addition to redness and swelling, the venom can cause nausea, vomiting, diarrhea, muscle pain, sweating, weakness, headache, urine discoloration, and abdominal pain.

Every year, about 35 people are bitten by these snakes. Because this snake is so common throughout eastern Australia and is so frequently encountered by humans, that is actually a very low number. However, there aren’t any confirmed deaths from its bite. There are a few older records that say its bite killed someone, but these have never been confirmed.

A snake catcher holds a Red-Bellied Black Snake by the tail

About 35 people are bitten by red-bellied black snakes each year.

©Ken Griffiths/


These snakes are indigenous to the east coast of Australia, including Victoria, New South Wales, and Queensland, and a population is also in South Australia. They are semi-aquatic and often live near bodies of water. They can be found in or near woodlands, grasslands, forests, swamps and other wetlands, streams, and shallow rivers. They prefer tall, thick vegetation to hide in, but they are cold-blooded, so they also like areas with patches of direct sunlight. They are sometimes found near drainage ditches.

A Red-Bellied Black Snake Swimming

Red-bellied black snakes often live near and hunt in shallow water.

©Ken Griffiths/


Red-bellied black snakes are carnivorous, with their diet mainly consisting of frogs and tadpoles. They also eat lizards, fish, eggs, small mammals, and snakes. They are cannibalistic and will not only eat other snakes but eat their own species.

They are opportunistic when it comes to food sources and as they are semi-aquatic they are able to hunt prey underwater typically by dipping in either their heads or tails but also by swimming.

These snakes have been observed to eat their food fast, consuming it before the venom has taken effect.

pet tree frog — Australian green species

Frogs form a large part of the red-bellied black snake’s diet.

© Sophie

Predators and Threats

The primary predators of red-bellied black snakes are feral cats, large birds of prey such as the brown falcon, and humans.

Baby or young red-bellied black snakes are more vulnerable and targeted by a larger number of predators including birds such as kookaburras, larger snakes, frogs, and redback spiders. If a snake consumes a cane toad, which is a widespread invasive species in Australia, it can die as the toxins in the toad are strong enough to kill it.

Kookaburras are terrestrial tree kingfishers of the genus Dacelo native to Australia and New Guinea.

Kookaburras prey on juvenile snakes including the red-bellied black snake.


Reproduction and Lifespan

Male and female red-bellied black snakes can have multiple partners during the breeding season, which occurs usually in October and November but can be as early as July to September. Males will seek out suitable mates by traveling up to 1.2 km or 4,002 feet per day and if more than one male is competing for a female’s attention, they will battle it out.

Females sometimes congregate together toward the end of a pregnancy. A few individuals will group together when they rest, presumably following the ”safety in numbers” idea, but no one knows for sure why.

The gestation period is for 4-5 months, with the female red-bellied black snake birthing 5-18 live young that typically are around 22.8 cm (9 in) and weigh about 10.1-11 g (0.35-0.38 oz) that are instantly independent. Red-bellied black snakes reach sexual maturity at around 2-3 years.

It’s not known how long red-bellied black snakes live in the wild. In captivity, the longest lifespan recorded for these snakes is 11 years.

A Red-Bellied Black Snake peeks out from foliage

The male red-bellied black snake will travel long distances to seek out a suitable female mate.

©Belle Ciezak/

Population and Conservation

While there is no known estimate of how big the red-bellied black snake population is, these snakes are listed as being of Least Concern by the IUCN. Since they can give birth to up to 18 live babies at a time, with the size of the young also an advantage, and live in so many different habitats, they are not at high risk of decreased population at this time.

As they live on a varied diet of lizards, fish, frogs, and other snakes, their food sources are plentiful. In addition, they can also hunt in or out of water.


The IUCN lists the red-bellied black snake as Least Concern.

©Tobias Arhelger/

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About the Author

Catherine Gin has more than 15 years of experience working as an editor for digital, print and social media. She grew up in Australia with an alphabet of interesting animals, from echidnas and funnel-web spiders to kookaburras and quokkas, as well as beautiful native plants including bottlebrushes and gum trees. Being based in the U.S. for a decade has expanded Catherine's knowledge of flora and fauna, and she and her husband hope to have a hobby farm and vegetable garden in future.

Red-Bellied Black Snake FAQs (Frequently Asked Questions) 

Is a red-bellied black snake poisonous?

A red-bellied black snake is not poisonous, but it is venomous. It is not an aggressive species and for its size, its venom is comparatively weak.

Is the red-bellied black snake rare?

No, though red-bellied snakes are somewhat rare, red-bellied black snakes are not.

How venomous are red-bellied black snakes?

The venom of a red-bellied black snake is quite toxic to humans, though bites are relatively uncommon with fewer than three dozen per year, but there are no recorded deaths as a result of the venom from their bite.

Where do red-bellied black snakes live?

Red-bellied black snakes are found in the swamps, wetlands, woodlands and grasslands of the east coast of Australia.

Why is it called a red-bellied black snake?

It is called a red-bellied black snake because the snake is primarily black, with a red underbelly.

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  1. Wikipedia, Available here:
  2. Animal Diversity, Available here:
  3. TrishansOz, Available here:
  4. Weebly, Available here:
  5. Australian Museum, Available here:
  6. Wildlife Victoria Government Australia, Available here:
  7. Savannah River Ecology Labratory, Available here:
  8. Rampfest Hudson, Available here:
  9. Animals Mom, Available here:

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