Encounters with neighbours of a different kind!

Text Pat McKrill Photographs Pat McKrill and Nick Evans

Although they might be everywhere around us, snakes are the most unobtrusive of animals. Unfortunately however, they are needlessly killed on sight, with little or no thought going into the reasoning for this slaughter. There’s a huge amount of detailed information available on snakes at any reputable book store, but in this article I’m going to concentrate more on the behavioural side to try and put another perspective into the subject, giving the reader, I hope, a better understanding of these grossly misunderstood creatures – animals that I like to refer to as our ‘neighbours‘- because that’s exactly what they are. They see us every day, they know what car we drive, they know where our kids go to school, but fortunately for us, our domestic tribulations remain a secret – they’re deaf.

Snakes are natural predators, and amongst the 150-odd species in South Africa, there are diverse food preferences that include such things as other reptiles, amphibians, eggs, fish, birds, mammals, slugs and centipedes – all found in abundance in our space. It’s always seemed strange to me, that although we lay the tables (water features, bird feeders etc.) with sumptuous food, make the rooms (garden shed, compost heap, wood pile etc.) eminently inviting for the guests, we then beat them to a pulp when they arrive to take us up on our invitations. Snakes themselves are preyed upon by just about anything with a mouth, and they’re solitary creatures, found only in larger aggregations during hibernations, hatchings or mating parties.

Despite the grossly unfounded but legendary stories of their inclination to attack everything in sight, snakes are not naturally aggressive, in fact they’re extremely shy, and although they have the ability to bite, they’re unlikely to do so unless roughly handled or directly threatened. For the purposes of this article, I’ll briefly discuss my top ten of those species that Highway residents could come across in their local surrounds or gardens. Not all snakes have venom, and of our Southern African species, probably only about 15 or so will have venom that could be considered medically important to humans, and Highway area readers might be interested to note that they enjoy a fair representation from that category!

As we’re now at the height of the ‘snake season’ let’s look at some of those we might come across; and whilst doing that, don’t ignore what reptiles have contributed to medicine, and more importantly, let’s not forget the primary reason they’re here – they’re a biological control, without which we’d certainly be living in an environmental nightmare.

The Big 5: highly venomous

Boomslang

Dispholidus typus

Male boomslang, photo by Pat McKrill
Female boomslang, photo by Pat McKrill
A large tree snake that can grow up to about 1.8m – 2m. Males are usually green, sometimes exhibiting interstitial (between the scales) skin that is blue or black, and females are usually brown, for the full length of the upper body. The lower half of the head and body is lighter in colour, almost off-white. Sexual differentiation in juveniles is not as distinct, but the head looks disproportionally large. The large eye and the ‘keeled’ scales (the scale has a longitudinal ridge that divides it into two halves) are diagnostic. They feed mainly on chameleons and birds, sometimes taking eggs – and because of this, they often get mobbed by birds. When threatened, they might inflate the throat in a display very similar to the warning display given by chameleons. An even-tempered snake, yet one must always exercise caution in its presence.

Vine Snake

Thelotornis capensis

Vine Snake, photo by Pat McKrill
Vine Snake, photo by Pat McKrill
Grows to about 1.8 metres, more slender than the Boomslang. Colouration is an amazing blend of subtle pinks, blues, reds and browns spread along the body in a pattern that defies description. Apart from the head with the diagnostic keyhole pupil and ‘tear drop’ below the eye, the rest of the snake looks like a twig, hence the name. Their primary food source is nesting birds, but chameleons and common river frogs are also on the menu, bringing them into contact with those homeowners with the more ecologically friendly gardens. Although very shy and even-tempered, as with the Boomslang, don’t be tempted to lapse into a false sense of security – give them space.

Mozambique Spitting Cobra

Naja mossambica

Mozambique Spitting Cobra, photo by Nick Evans
Mozambique Spitting Cobra, photo by Nick Evans

Very common in the Highway region, growing up to about 1.5m in length, and fairly robust in stature. A major contributor to the national bite statistics, often getting trodden on as evidenced by the number of bites to the lower extremities, this snake is a ground forager with a liking for toads, rodents and other snakes. Like most snakes, it will readily hide, but it will not hesitate to spit at its aggressor if it feels threatened. Although cobras would generally display a warning hood as soon as they are disturbed, this snake is an exception, and can spit from the prone position, giving no warning display. The venom can be sprayed for anything up to about 3 metres. Scales range in colour from a light through to a reddish brown, separated by dark interstitial skin, and it can be confused with a few other snakes at first glance, so take extra care if approaching it. Apart from getting spat at to confirm your diagnosis, identity can be further confirmed by the throat bands that it displays if it shows a hood. Which also tells you by the way, that you’re too close.

Mozambique Spitting Cobra photos: Nick Evans

Black Mamba

Dendroaspis polylepis

Black Mamba, photo by Nick Evans
Black Mamba, photo by Nick Evans

Probably South Africa’s best-known snake for all the wrong reasons, Mambas have an unfortunate reputation that with few exceptions, is undeserved. That being said, they can still be dangerous if cornered or roughly handled. More common in the gorge areas and on the periphery of heavily populated areas, where their primary diet of rodents and birds can be found. Growing to in excess of 4metres, Black Mambas are shy but skittish, and will defend themselves if harassed. Because of their size, they become fairly territorial, but if left to their own devices, they will pose no threat. If they are aware of a presence, human or animal, they will retreat into their hiding places. Black Mambas will enter human dwellings in search of food, and there are often sightings of mambas near so-called informal settlements, where rat infestations are known to occur.

Black Mamba photos: Nick Evans

Puff Adder

Bitis arietans

Although once commonly found throughout the country, the Puff adder is subject to the effects of habit at destruction, and there are pockets where it no longer occurs. It’s a typical ambush feeder, killing its prey, mainly rodents, by striking out, injecting the venom and retracting, all in one swift movement. It will then follow up on the scent of the prey animal, which is unlikely to have moved too far off before dying. Known to exceed 1.3m in length, they are squat in structure with a large head and narrow neck, with a regular light brown to bright yellow chevron pattern – chevron pointing backwards – overlaying their base colour which varies from light brown, to yellow, brick red and almost black, running the full length of the body. The scales are heavily keeled. Like all snakes, puff adders are ectotherms, often basking in sunlit areas, which, along with their tendency to ambush animal tracks would explain why they are credited with more accidental bites than any other snake in the country, with locals and hikers being the most vulnerable. They get their name from the heavy hissing they use to warn other animals of their presence.

The Little 5: mildly venomous or non-venomous

Rhombic Night Adder

Causus rhombeatus

Night Adder, photo by Pat McKrill

This common Highway forager eats amphibians, mainly toads, and the common name is to some extent a misnomer as it looks for food at any time of the day or night. In the frog season you can expect to receive the occasional visit, and if the accommodation is really good – terraced wall, pool pumphouse etc. – there’s a chance you might acquire a permanent resident. They might hiss and mock strike if a close encounter ensues, but will always try to hide, so before you rush out and trash the water feature, bury the garden gnome and concrete in the flower bed, try to understand that casual visits by snakes to your spot are probably taking place all the time, it’s just that for most of the time, you’re unaware of them.

They can grow up to about 800mm, slightly longer than an adult arm measuring fingertip to shoulder, and unlike the typical adders, they are not as ‘squat’, having no defined neck. Their scales are very lightly keeled and their skin has a satiny sheen to it. The base colouration ranges from light brown through to almost blue/ grey between different specimens, superimposed upon which is a series of diagnostic, evenly spaced rhomboid shapes from whence they get their name. There is a very distinct arrowhead marking on the top of the head, pointing forward. A bite is painful but the venom is not known to be life-threatening.

Herald Snake

Crotaphopeltis hotamboeia

Herald snake, photo by Pat McKrill
Herald snake, photo by Pat McKrill
Often found where Night adders would occur, Heralds are also frog eaters and have adapted well to human habitation, being frequent visitors to suburban homes. They grow up to about 800mm, their base colouration ranges from olive to dark grey, sometimes interspersed with a white fleck pattern along the dorsal surface. The belly colour is a creamy white, and the head is always darker than the body, sometimes with a reddish upper lip. As their ‘cat’s eye’ pupils would suggest, Heralds are nocturnal. When encountered, their defensive tactics consist of flattening the head, coiling, hissing and striking out, but because of their weak venom, they can’t be classed as dangerous. A typically inoffensive ‘garden snake’.

Bibron’s Stiletto Snake

Atractaspis bibronii

Stiletto snake, photo by Pat McKrill
I’m reminded of a comment made in the early 1900’s by Dr V.F.Fitzimmons, to the effect that the grossly oversized fangs on this snake seemed to him to be an evolutionary overkill that would undoubtedly correct itself in time. No such luck. This black snake with a cream coloured underside, reaching about 600mm in length, looks like a harmless blindworm, yet it’s anything but. Although inoffensive in nature, in self-defence it can inflict an excruciatingly memorable bite, by drawing its head backwards and sideways, inserting a single, extremely long fang into its aggressor – without having to open its mouth! Do not pick it up. They hunt at night, eating frogs as well as other snakes, spending most of their time underground.

Brown House Snake

Lamprophis capensis

Brown house snake, photo by Pat McKrill
A well-known non-venomous South African constrictor that hunts at night, often seen basking on warm roads at night – unfortunately sometimes with unintended consequences, putting it high on the road-kill stats. The basic colouration varies regionally through the brown spectrum, but the twin rows of diagnostic head stripes are always present. It’s a very even tempered snake that keeps the rats and mice honest, and a great snake to have around the garden or in the shed. It will habituate easily provided the right food and shelter are available and can live to probably in excess of 15 years. It’s not aggressive, but will bite if roughly handled. A well-fed resident female can grow up to about 1.5 metres in length and, like a number of species, can store fertile sperm for a few years after an initial mating process, laying about 12-15 eggs at a time when the mood takes her.

Spotted Bush Snake

Philothamnus semivariegatus

Spotted bush snake, photo by Pat McKrill
One of the 4 or 5 green species that occur in the Highway area, this guy is the reptilian equivalent of the Jack Russel. Here, there, everywhere at the speed of light, in search of geckoes, tree frogs and something to mate with. This Twiggy-like snake grows to about 1.2m in length and the base green colour is complimented with black spotting along the first third of the body. Commonly found in garden hedges, the garage, kitchen and the ironing room, where it hunts geckoes, using brute force and guile to subdue and swallow them. Completely harmless and great to have around.
Author photo: Pat McKrill

About the author

Pat was born in the UK, educated and brought up in Rhodesia/Zimbabwe, and came to South Africa in 1983. He developed an early interest in the study of the behavioural aspects of insects and animals, rather than the deeper scientific side, and he’s worked with snakes for most of his life. Pat conducts educational walks and talks throughout SA and into neighbouring countries where snakes are grossly misunderstood and needlessly killed. He writes articles for a number of publications, and has written the book ‘Getting to Know the Neighbours’, which is all about understanding snake behaviour and is aimed at teaching others how to come to terms with them.