Red Bellied Black Snake What is a Red Belly Black Snake?
The red-bellied black snake is a medium-sized venomous snake with a glossy black upper body with striking bright red or crimson sides and belly. It one of the most frequently encountered snakes on the east coast of Australia, and accounting for approximately 16% of all snake bites. It is a very shy and non-aggressive snake which prefers to avoid humans rather than attack. The red-bellied snake is typically diurnal, but may become nocturnal during hot or dry weather.
It is also called the Red Belly Black Snake or Common Black Snake. Its correct non-scientific name is Red-bellied Black Snake. Its scientific name is Pseudechis porphyriacus.
The red-bellied black snake's head is barely distinguishable from its body. That is to say, there isn't a clearly visible constricted neck area. Its snout is usually a pale brown colour. The scales on its body are smooth and glossy. It has medium sized, very dark eyes with round pupils that sit below a noticeable brow-ridge.
The average adult is about 1.5 - 2m long, with males growing slightly larger than females. Some have been known to grow up to 2.5 metres in length, making it one of the largest venomous snakes in Australia. The red-bellied black snake likes to maintain a body temperature of between 28 to 31º C during the day. Being a cold blooded animal, it does so by moving from sunny positions to shady positions to main its body temperature.
The red-bellied black snake belongs to the elapid family of snakes which means it has hollow syringe-like venom injecting fangs located in the front of its mouth. The fangs on this snake are relatively small. Like most snakes it is deaf, has a forked tongue, and no eyelids. It is a very shy creature that prefers to avoid humans. A red-bellied black snake can live for up to 6 years.
Geographic Distribution of the Red Bellied Black Snake
Red-bellied black snakes are found along the eastern seaboard of Australia, from south-eastern Queensland through eastern New South Wales and Victoria. They can also be found in in parts of the Mount Lofty Ranges of South Australia. They can be found in small areas of north-eastern Queensland. (See map).
Red Bellied Back Snake Range
Red-bellied black snakes live in moist habitats within forests, woodlands and grasslands close to bodies of shallow bodies of water such as rivers, streams, swamps and wetlands. They have also adapted to the modern rural environments and can be found close to irrigation canals and dams. They rarely venture more than 100 meters from water. The snakes shelter under large rocks, in logs, in animal burrows and in clumps of grass. They seem to be territorial and have a number of preferred shelters within their domain. They are active mostly during the day and during warm evenings and nights.
Red-bellied black snakes predominantly eat frogs and tadpoles. They also eat lizards, fish, eggs, small mammals and other snakes—including members of their own species. Red-bellied black snakes may sometimes slither up trees for several meters in search of prey.
The snake is known to forage in water where it may submerge itself completely and swim underwater in search of prey. It can stay submerged for as long as 23 minutes. It may also intentionally stir up underwater sediment to flush out hidden prey. Captured prey may be swallowed while still under water or, if large, brought to the surface to be consumed.
Red-bellied black snakes usually mate during spring, around the months of October and November. During the breeding season they will fight other males to gain access to a female. Jousting involves the two rivals spreading their necks and rearing up their fore-bodies and twisting their necks around each other and getting entwined during the struggle. The snakes may hiss loudly and bite each other (they are immune to their own species' toxin). This jostling usually lasts for less than half an hour with one of the contenders conceding defeat by leaving the area.
The female gives birth about four to five months after mating. Red-bellied black snakes are ovoviviparous. That is, they do not lay eggs like most other snakes. Instead they give birth to between 8 to 40 live young each in their own individual membranous sac. The young break through this membranous sac soon after birth. They are about 122mm in length at birth. The babies are born with well-developed venom glands. Their bite is just as toxic as that of their parents. Most young do not survive to adulthood. They fall prey to birds such has the kookaburra, other snakes and frogs, etc. A red-bellied black snake reaches sexual maturity at around 2 to 3 years.
The red-bellied black snake does not have any significant predators. It is not a threatened species. There are many of these snakes in the wild. They are, however, susceptible to the following threats.
Cane Toad Poisoning
There was some initial concern about the rapid decline in population of the red-bellied black snake after the introduction of the Cane Toad in the 1935. The snake was eating the highly toxic toad and dying. It appears however that the snake and cane toad seem to be co-existing in the wild. There are two theories put forward. The first is that the snake has learned to avoid eating the toad. The second is that natural selection is at play as it appears that the snakes have gradually got longer since the 1937. While a single cane toad could poison a smaller snake the large snake, due to its bigger body mass, could survive a single cane toad ingestion. So natural selection has favoured bigger snakes.
Feral Cats & Raptor Birds
Given the human fear of any snake, many of these harmless animals are killed when humans encounter them.