Carpet Python

Carpet pythons are the most widespread group of pythons in Australia, occurring across much of the mainland. Robust snakes, they may vary considerably in colour and form.The carpet pythons from the rain-forests of northeastern Queensland can be a striking black or dark brown with long bold yellow stripes or blotches.

The so called Diamond Python that occurs along the east coast from  southern New South Wales to Victoria is the one encountered by many people: olive black with  creamy yellow rosettes along the body. Other variations occur in inland, northern and Western  Australia.

Carpet pythons are generally ambush predators rather than active hunters. They select a spot next to a trail used by other animals and lie in wait.

Amethystine Python

The Amethystine Python, which is also known as the Scrub Python, is Australia’s largest snake. Specimens have been measured at more than 8.5 m in length but this is quite exceptional and a 5 meter snake is regarded as very big.

The name of this species comes from the milky iridescent sheen on its scales,which gives it an amethyst-like colour. Unlike many of the very big boas from overseas, this snake has a slim body.

Just the same it can eat large prey and will kill and eat wallabies and bush pigs. More often it takes  birds, fruit-bats, possums and similar sized mammals. It is usually active at night and younger animals are mainly tree dwelling.

The large adults are more terrestrial but they are still quite capable of getting up into the trees, male Amethystine Pythons are aggressive with one another during the mating season and at such times they will engage in combat.

Childrens Python

Children’s python is a name applied to a group of three small pythons. Contrary to popular belief their name does not signify that they are pythons for children; it is in fact the name of an English naturalist, JG. Children after whom the snakes were named.

They are, however, popular snakes with reptile keepers and are a good species for young people to keep because of their small size and placid temperament.

Children’s pythons occur over much of Australia and are often associated with rock outcrops and caves where they are very adept at catching bats.They will climb a rock face at the entrance to a cave where bats are roosting and wait there until the bats fly out in the evening.They will catch a bat flying past and eat it hanging in mid-air,secured to the rocks only by their tails. They also eat frogs, lizards and rodents.

Water Python

The Water Python is a northern Australian species that, as its name suggests, is usually associated  ith water. It is found around freshwater billabongs,watercourses, lagoons and swamps and feeds on mammals, birds, particularly waterbirds, and reptiles. It is also known to eat birds’ eggs. The Water Pythons around Fogg Dam near Darwin have been found to occur in huge numbers.

Their biology is tied in to that of the water rat ,which is also abundant there. The only food in  sufficient quantity for newly hatched Water Pythons to eat are baby water rats. If the rats fail to breed or breed too early, then only very few baby pythons will survive from that year.

Woma Python

Pythons generally constrict their prey by coiling around it and increasing the pressure every time the animal breathes out. The prey then suffocates as it cannot draw another breath.

The Woma or Sand Python has a different strategy. It locates much of its prey down burrows where there is not enough room to coil and constrict. Instead the Woma squashes the victim against the burrow wall with its body. Womas may often be found with scarring on their bodies where victim did not give in quietly.

These pythons are also known to lure prey by wriggling the end of their tails in much the same way as death adders. As a consequence, adults of this species may be found with part of their tails  damaged or missing where a curious bird, mammal or reptile has had a snap before being attacked itself.

Salt Water Crocodiles

The Saltwater Crocodile is a far more formidable animal than its freshwater relative, and it does eat people.While normally found in estuaries and tidal rivers, these crocodiles also inhabit fresh water and will go out to sea. The smaller Saltwater Crocodiles feed on insects, frogs, small fish and  reptiles.The larger ones will eat fish, birds, reptiles and whatever other suitably sized animals they can get, including wallabies.

In the wet season females construct a nest of vegetation and soil and lay their eggs within. The eggs are left to incubate in the heat generated by the rotting vegetation. Mortality of eggs in nests is high,often because flooding covers the eggs with water and the embryos drown.

The females remain near their nests and will defend them from intruders It has been estimated that about 20 per cent of the eggs laid in a season actually hatch, and less than 1 per cent will reach maturity. As with Freshwater Crocodiles, the female will remove hatchlings from the nest and take them to the water.

Freshwater Crocodiles

The Freshwater Crocodile is smaller than the Saltwater Crocodile and has a narrow snout. It feeds on such prey as frogs, shrimps, fish and insects but will take anything of a suitable size. It is not regarded as dangerous to swimmers, although a close eye would be need to watch over children. Freshwater Crocodiles will bite if harassed.

Found only in northern Australia, the Freshwater Crocodile inhabits permanent freshwater swamps, billabongs and rivers. it may also move into the tidal areas of some rivers where the Saltwater Crocodiles are absent or low in numbers.

Nesting and Growth

During the dry season a female crocodile digs out a nest on a sandbank, lays her eggs and covers it over with sand. Several females may use the same area to nest, so sometimes a nest of eggs will be excavated by another female as she digs her own nest.

When they are born, the young call from the nest and are dug out by an adult female, who till carry them to the water in her mouth. Females will remain with groups of hatchlings for several weeks to protect them from predictors. During this period the mothers can be very aggressive.

In the upper reaches of the Liverpool River in Arnhem Land in the Northern Territory, the Freshwater Crocodiles exhibit extremely stunted growth. This seems to be related to their habitat which is somewhat rocky and lacking in food. Although they are mature the crocodiles here are considerably smaller in both size and weight compared to those found on coastal plains where food is more plentiful.

How do snakes swallow large prey?

Small snakes tend to eat small prey such as lizards, which do not present the with any problem. Large snakes however, find it more efficient to take large prey and they must have a way of eating and digesting them.

To achieve this they are able to drop their lower jaw at the back as well as the front. The lower jaw also stretches sideways as it is joined at the front by a very elastic muscle.  This means not only can it stretch its mouth wider horizontally but it can also work one side of its jaw forward independently of the other side.

The snake can literally 'walk' its mouth over over the pray using its teeth to anchor and pull forward. Also, a snakes skin is very flexible, allowing i to eat animals that have a larger diameter than itself.

There are other adaptations to help snakes eat large prey. Firstly,

• Their brain in encased in bone; this protects it from any kicks of its prey while struggling to escape.  
• Snakes have a tube in the throat called the 'Glottis'; which is able to protect forward beyond the lower jaw so the snake can breathe while eating, 

The advantage of being able to eat large food items is that you do not have to eat as often. Snakes can go for many months without eating and it is probable that large snakes eat only a few meals during a year. It is more efficient to catch and eat larger prey rather than spending lots of energy chasing smaller animals.

How do snakes eat and digest food?

All snakes are carnivorous; meaning that they eat other animals. They do not eat vegetable matter and generally they catch and eat living prey, although instances have been recorded of snakes eating road-killed animals.

Because most cannot dismember their food they must eat it whole, so the select prey that can be swallowed easily or they have adaptations to cope with large prey. In some species the oung and adults eat the same but different sized prey.

In other species, there is a shift as the snake grows. For example, hatching carpet pythons eat small skinks but the adults eat rabbit, rats, possums bandicoots and even wallabies.

Digesting their food

This is where venomous snakes have an advantage over the non-venomous ones because the venom they have helps break down the tissue of the prey and also speeds up digestion. Whether venomous or not, snakes still have to keep their body temperature up to aid digestion.

If they are too cool, digestion is slowed down and there is a possibility that the prey will rot in the snakes stomach and kill it. That is why when a snake has eaten large prey it will often bask in the sun for extended periods.

How do snakes move?

With up to 400 vertebrae, snakes have remarkable flexibility and some can travel at up to 10 kph. There are four different ways in which they may move.

The usual method is an Undulating movement in which the snake uses irregularities on the ground to get leverage and push it's body against. Done at a number of points along the body at the same time, this creates a constant undulating flow. Brown snakes and whip-snakes move like this.

Then there is the slow Straight-line way of moving used by large and bulky snakes such as Pythons. The head and fore-body are stretched straight forward. The belly scales then gain a hold and the snake advances by contacting its body muscles and dragging the rest of itself forward.

In the Concertina method sometimes adopted by Brown-tree-snakes, the snake forms a series of body loops and then pushes its head and fore-body forward. Having obtained a purchase, it draws the body loops forward and the process is repeated.

Sidewinding is a means of locomotion used in soft sand or mud whereby a snake moves diagonally along a surface. The White-bellied Mangrove snake, for example, sometimes moves by sidewinding. It pushes its head and neck against a surface and flicks its body forward in a loop. Once the tail and back part of the body gain a grip, it flicks it's body forward in a loop again.

How can i recognise a venomous snake?

There is no absolute method of telling a venomous snake from a non-venomous snake bit it is certainly a good idea to know which dangerous snakes can be found in your area. Take time to look at photographs in an appropriate field guide so you can identify your local dangerous snakes.

Some can be readily identified because of their body form and size but colour alone in an unreliable guide to identification as there is a great deal of variation in colour within many species.

It is worth remembering that although 70% of Australian land snakes are venomous, only 20% are regarded as being dangerously venomous. In Australia less than 5 people die form snake bites each year, despite being the country with the most venomous snakes in the world.

There are several reasons for this. One is the that our snakes have short fangs, snakes mostly inhabit remote areas of Australia where few people live and medical staff are highly trained and proficient in dealing with snake bites.

Which snakes are venomous?

There are three venomous snake families in Australia;

• Elapids
• Sea Snakes
• Sea Kraits 

All the Elapid snakes are venomous, although most are only mildly so ans are not considered to be dangerous. They all have fixed hollow fangs in the front of the upper jaw, connected on each side by a duct to the venom gland. There are 15-23 scale rows around the mid body, excluding the broad belly scales.

The completely aquatic Sea Snakes have vertically compressed paddle-shaped tails and nostrils which are situated on the top of the snout with flaps that close when the snake is submerged. The vast majority of sea snakes are very venomous are rarely encountered.

While essentially marine snakes, the Sea Kraits do com onto land, particularly to lay eggs. All are characterised by numerous black cross-band and laterally placed nostrils. Although very poisonous sea kraits are reluctant to bite and are also rarely encountered.

Which Australian snakes are non-venomous?

Not all snakes are venomous ans indeed most venomous snakes are dangerous. There are far more non-venomous snakes than venomous ones worldwide, but in Australia the opposite is the case and the majority are venomous. Unfortunately unless you are familiar with snakes it is not possible merely by looking to tell if a snake is venomous or not.

In Australia, four of our seven families are regarded as non-venomous;

• Blind snakes
• Pythons
• File snakes 
• Colour-blinds

The Blind snakes have small shiny worm like bodies with blunt heads ans short tails that end in a spine. Their eyes are reduced to dark spots and the scales are a uniform size around the body (with one enlarged on the belly as in some other snakes). When handled, they have a tendency to emit a strong, pungent odour.

Pythons are muscular , usually heavily built and slow moving. Most Australian pythons have heat-sensing pits in some of the scales of their lips. They all have 30 or more scale rows around the middle of the body and their belly scales are larger than the others. All pythons possess surs(whic are the vestiges of ancestral hind limbs) on either side of their vent.

The File snakes are totally aquatic and have large bodies with baggy skin. Unlike the paddle-like tail of the typical sea snakes, the tails of the file snakes are narrow and can grasp things, so they are useful 'anchors'. The scales are small, very rough and rasp-like.

The Colour-blinds are found across northern Australia and down the east coast. These snakes may be completely non-venomous, although some have enlarged, grooved, poison-conduction fangs at the back of their mouth but even these are not regarded as dangerous.

How do reptiles keep warm?

After the cool of the night reptiles have to warm up in the morning sun. This they do by basking until their body temperature is high enough to start their daily activities. Some reptiles flatten out to expose a greater body area to heat and so warm up quickly.

In colder climates many reptiles have dark bodies allowing them to absorb greater heat than will a paler body. You may have seen lizards lying on bitumen roads, particularly in rural areas. The black surface absorbs the heat from the sun and lizards often flatten out on the road to absorb this heat a bit like an electric blanket.

During the day reptiles shuttle between sun and shade in order to keep their temperature at the desired level. If it gets too hot, they will disappear into shelter. Nocturnal reptiles can operate at lower temperatures. Some of these will actually heat up under cover bu selecting sheltered spots that gets the afternoon sun.

Reptiles cannot just keep heating up all day. There is a critical point at which the temperature becomes lethal That point does vary between species but it can exceed 40 degrees C. If the reptile cannot reduce its body temperature, it will very quickly die. They must keep warm enough to be able to carry out their daily activities, but must also be wary of overheating.

Are reptiles cold blooded?

Reptiles are often refereed to as 'Cold blooded' animals, which is an over simplification of a complex arrangement. Reptiles are Ectotherms, this means that they rely on external heat sources to maintain a constant body temperature. Because they have no internal mechanisms to generate heat, they must seek out warmth .

Reptiles are therefore most numerous in tropical or hot and arid areas where the air temperature is high as they do not want to spend a lot of time warming up.

As they do not maintain a high body heat, they require far less food than mammals or birds of a similar size and so the have been able to successfully colonise areas that cannot sustain high numbers of birds and mammals.

Reptilian Records

Did you know that some reptiles like python and crocodiles never top growing?

Their growth rate slows right down as they get older, but in theory they can keep on growing into giants if they live long enough.

In Australia, the Amethystine Python from northern Quensland has been recorded as exceeding 8 meters and is Australia's largest snake.

The largest snake in the world is the Aazonian Anaconda, which is reputed to grow to lengths of 10 meters and more.

The largest Australian lizard is the Goanna, the Perenti which can reach 2.5 meters in length. The largest lizard in the world is the Komodo Dragon, which can be found on the Indonesian islands of Komodo, Rinca, Flores, Gili Motang, and Padar

How long do reptiles live?

Not very much is known about the longevity of most reptile species in the wild but there is plenty of information on reptiles kept in captivity. Certainly Blue-tongue, Water-dragon and other similarly sized lizards have been kept in captivity for 20 to 30 years.
The smaller species are not so long lived, but some Geckos have been reported to live in captivity for around 10 years.

Snakes are remarkably long lived in captivity ans some have been kept up to 20 years. In the wild they are unlikely to live as long. A less assured food supply, greater risk of predation and other hazards would reduce their life expectancy significantly. Some species are known to only live for one or two years in the wild.

A curious feature of reptiles is that no matter how long they live, they continually replace their teeth. This is in contrast to mammals, which lose their teeth when they get old.

Why do reptiles have scaly skin?

Most people know that snakes and lizards are reptiles. Turtles and Crocodiles are also reptiles but frogs (which are amphibians) are not. Reptiles are vertebrates that breath air and depend on outside sources for body heat.

The most obvious feature of reptiles is their non-porous, scaly skin. This helps to greatly reduce water loss from the body; as a result they do not need constant access to water.

Some reptiles get all their liquid requirements from the prey they eat. This ability of reptiles to conserve body fluids means that they are able to successful y inhabit very dry and arid parts of Australia.