Snakes not only form part of South Africa’s rich biodiversity but also play an important role in fynbos ecology. Southern Africa has 171 recognoised snake species of these 72 are non-venomous, 50 mildly venomous, 29 are able to inflict painful bites and 20 are considered potentially deadly. Summer is snake season in the Western Cape and the Province is rich in species, most of which are harmless. The species has been misunderstood and feared for to long and are in need of more friends, education via proper information is an ongoing priority.
CHARACTERISTICS OF SNAKES
- Snakes are elongated, limbless carnivorses that are specialised in eating large, infrequent meals, that can exceed their own body mass.
- The body is covered in either keeled or smooth scales. Keeled scales have a ridge in the centre of the scale while smooth scales do not.
- Their jaws are not fused together, but are connected by a very elastic ligatment that allows the two havles to move independantly from one another.
- Snakes do not have eyelids but instead their eyes are covered by a translucent scale.
- Snakes have a forked tongue which they use for smell.
- Teeth are specialised for piercing, injecting venom and holding on to prey rather than slicing or chewing and snakes often eat their prey whole. Snakes can be grouped into one of four categories based on their teeth and fangs namely Solid-toothed, Back-fanged, Fixed front-fanged and Hinged front-fanged snakes.
- Most lay soft shelled eggs while some give birth to live young e.g. the Puff Adder, Rinkhals and Mole Snake.
- Snakes are poikilothermic and have no internal mechanism to control their own body temperature and instead make use of their enviroment to maintain a comfortable body temprature.
- In areas where there is marked difference between the ambient temperatures of winter and summer snakes will often go into hibernation during winter. During this time they live off their body fat and show very little or no activity.
- The skin of snakes do not grow with their body and is shed several times througout the year depending on the growth rate.
- The tongue carries chemicals in the air to a special organ on the roof of the snakes mouth know as the Jacobson’s organ.
- Snakes can strike faster than the blink of an eye and up to 1/3 to 1/2 of its body length.
- Snakes move in four basic ways and most will use more than one type of movement depending on the situation. These include (1) side-winding used by only a few desert snakes, (2) concertina-type which is when the head is anchored and the body dragged forward, (3) serpentine or lateral undulation used by most snakes when disturbed or chasing prey and (4) rectilinear motion which is a catepillar-like movement used by heavy-bodied snakes.
- The venom of snakes is produced and stored in modified salivary glands located roughly on either side of the head behind the eyes. Not only does the venom help kill prey it also helps with digestion.
- Snake venom can be divided into three categories haemotoxic , cytotoxic and neurotoxic and snakes each have one type of venom except the Mozambique Spitting Cobra, Berg Adder and Gaboon Adder which have a combination of two or all three. Haemotoxic venom causes continued bleeding as it stops blood from coagulating and occurs in snakes with grooved fangs such as boomslang. Cytotoxic venom leads to tissue distruction and localised bleeding around the bite and occurs in hollow hinged front-fanged snakes such as adders. Neurotoxic venom effects the nervous system causing difficulty breathing, nausea and vomiting and paralysis of the muscles and occurs in snakes with hollow front-fixed fangs such as cobras and mambas.
ENCOUNTERS OF THE REPTILIAN KIND
Snakes often come into conflict with humans when they occur in and around gardens, domestic residences and places of work. This is most likely because they seek either shelter, shade, water and/or food. More common than some may think, snakes are often found in the engine compartment of vehicles.
Overgrown gardens, garden refuse, log piles and accummulating rubbish which attracts rodents also attract snakes who are not the type to pass up an easy meal. They may enter buildings, sheds and roof spacings for shade or shelter and during hot and dry periods even a dripping tap is enough to attract a snake. Those with an affinity to water might decide to take a quick dip in ponds, bird baths and even swimming pools while some might even visit the beach to take advantage of the cooler air on the shore.
Some areas are surounded by pristine fynbos vegetation which is home to several species of snakes, both venomous and non-venomous and encounters may be more frequent. Generally speaking snakes, venomous or otherwise are best left alone. It is good policy to regard any unidentified snake as venomous until proven otherwise.
COMMON SNAKES OF THE REGION
There is a variety of non-venomous and mildly venomous snake species that are common in and around Darling and Yzerfontein. While there are three well known venomous snake common to the area namely the Boomslang, Puff Adder & Cape Cobra. Below are images of the more frequently encountered species.
Brown House Snake
Latin Name: Lamprophis capensis
Ranging from 40 to 70cm in length the light to reddish brown snake has a pearly white underside with a pale stripe on either side of the head. The brown house snake is nocturnal and feeds mainly on rodents.
Olive House Snake
Latin Name: Lamprophis inornatus
Ranging from 45 to 75cm in length the olive house snake can be a uniform olive-green, olive-grey, brown or black in colour. The olive house snake is nocturnal and feeds mainly on rodents, lizards and other snakes.
Latin Name: Duberria lutrix
The small snake is often between 25-30cm in length. In the Western Cape the colour is a uniform brown wit or without dark speckeling. Some species may have a reddish brown band running aloing the back. They feed on slugs and snails and are often found under rocks and logs in gardens. The are active during the day especially just after rain.
Latin Name: Dasypeltis scabra
Between 40 -70 cm but can reach up to 1m in length. Light-grey brown with darker brown square blotch markings. There is a distinctive forward facing V shape on the top of the head. They have keeled scales and eliptical eyes. Egg-eaters are nocturnal and feeds exclusively on bird eggs.
Latin Name: Crotaphopeltis hotamboeia
Venom: Mildly venomous
Between 40 -70 cm the body is an olive-green with white stippling which may be indistinct in some. The head is a blackish-brown above with or without red beneath the eye, running the length of the head. They are nocturnal and commonly found in gardens.
Latin Name: Psammophylax rhombeatus
Venom: Mildly venomous
Between 4 -75 cm in length the body is light brown to olive with three rows of dark-edged brown markings which sometimes form a zig-zag pattern. With or without red speckled markings along either side of the body. They are active by day and most often observed in the veld. Although rear-fanged they are considered harmless to humans.
Latin Name: Pseudaspis cana
A large snake that average just over a meter in length but can reach up to 2m in the Western Cape. They occur in any shade of uniform goldish-brown to black with a lighter coloured belly. Juveniles are boldy marked with spots and zig-zag patterns. Mole snakes are active during the day and are often found on farms or basking on the side of the road. They are non-venomous but will deliver a painful bite if molested. Image: Tyrone Ping
Latin Name: Dispholidus typus
A elusive slender snake that averages between 1-1.5m in length. The males in the Western Cape are usualy a blackish or greyish colour above with vody scales edged in yellow and a bright yellow belly. Females are a pale brown or olive or greyish-black with a yellow-cream belly. The large round eyes are a characterist feature of Boomslang. They are active by day and spend most of their time in trees and tall shrubs. An inoffensive species they will inflate their neck when annoyed. They are common in gardens with averies and on farms.
Latin Name: Naja nivea
Possibly one of the most iconic snakes of the Western Cape the Cape Cobra goes by many names. The Cape Cobra can reach upt to 1.8m and occur in a variety of colours; from pale creamy yellow, oragne yellow to dark brown and black. Some have dark stippling or blotches. Due to the variation in colour they are often confused with mole snakes. When disturbed it will lift the forepart of the body and spread a prominent hood. If left alone it will lower the body and move off. However a bold snake will stand its ground and if provoked will bite readily. A bite from a Cape Cobra is a medical emergency and the onset of symptoms is rapid. They are common on farms and in gardens and will enter buldings and conceal themselves in vehicle engines.
Latin Name: Bitis arientans
A large, robus adder averaging between 40-80cm in length. In the Western Cape they range from greyish to reddish-brown with yellow-black edged forward facing chevron-shaped markings. Scales are keeled. Due to their superb camouflage puffies are difficult to spot in the veld and may easily be trodden on. During summer they are mainly active during night time when it is cooler and they are often attracted to properties where rubbish is accumulated as they feed mainly on rats and mice. The puff adder will bite and strike readily if provoked and are one of the fastes strikers in the world.
Cape Reptile Institute
Sasol – First Field Guide to Snakes and other Reptiles of Southern Africa
FGASA Nature Guide Leaner Manual
African Snakebite Institue
Blouberg Snake Rescue