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MINIATURE GEMS OF THE LIVING DESERT

Péringuey’s Adder | Bitis peringueyi approaches, tasting the air with its tongue (Mike Watson)

The Living Desert is a well-known phrase and is perhaps the best way to describe the world's oldest desert, the Namib. Stretching from southern Angola, through Namibia and into northwestern South Africa, parts of this extraordinary desert are thought to have experienced arid conditions for up to 80 million years.

At first glance, the Namib can appear to be little more than a vast, lifeless sea of shifting sand, punctuated by some of the most spectacular dunes on Earth. They may not be the world's tallest; that is Duna Federico Kirbus in Argentina, which rises more than a kilometre above its surroundings, but the Namib's great orange and red dunes are surely among the most beautiful.

Look a little closer, however, and the apparent emptiness begins to disappear. Beneath the sand lives an extraordinary collection of animals, many of them mind-bogglingly specialised for desert life. Their adaptations are the product of the sheer length of evolutionary time passed, and this is why the Namib is so special. Survival here is an art of exploiting every available source of shelter, moisture and food.

The cold Benguela Current chills the air of the Atlantic coast of Southern Africa, suppressing rainfall, while persistent high-pressure conditions prevent cloud formation over much of the desert. The result is an extraordinarily arid environment, although coastal fog provides a vital source of moisture for its inhabitants.

It is also a landscape marked by death. Whales and seals left their bleached bones along the coast, while countless ships have fallen victim to the treacherous combination of fog, currents and surf. The result is the evocatively named Skeleton Coast; a name that conjures up images of shipwrecked sailors, although the original "skeletons" were the remains of marine mammals.

We were privileged to have some of the desert's wildlife treasures revealed to us by a couple of genuine local experts. Without them, we would certainly have missed some of the Namib's most elusive inhabitants, as well as being unable to access some of the best locations. Between them, Chantelle and Ben gave us some wonderful encounters and among them was a quartet of desert specialists; an A-list collection of herps, followed by one particularly accommodating little bird.

Péringuey’s Adder | Bitis peringueyi sidewinding down a sand dune in the Namib Naukluft National Park (Mike Watson)

NUMBER ONE: PERINGUEY’S ADDER

At the very top of everyone's wish list was Peringuey's Adder Bitis peringueyi, also known as the Desert Sidewinder or Namib Sidewinding Adder.

I was already contemplating a return to Namibia's Skeleton Coast after the disappointment of missing this extraordinary snake on our first desert excursion in Dorob National Park, near Swakopmund.

Our guide, Chantelle Bosch, is a veritable snake whisperer, in fact, it seems she can conjure almost every creature out of the sand. But even she was thwarted by a violent sandstorm, which had blown up in the morning. The wind blew hard for hours, completely obliterating the tracks and other signs that she would normally use to read the famous "Desert Telegraph".

So, it was a massive relief when, the following day, on our Sandwich Harbour excursion in Namib-Naukluft National Park, south of Walvis Bay, Ben Bryden simply said:

"We can find it too, no problem."

And, indeed, he did.

Ben is usually free to concentrate on other things, such as driving the enormous dunes in his modified Landcruiser, when visitors have already had the full Living Desert experience with Chantelle the previous day. Like Chantelle, Ben is a protégé of the legendary Namib Desert guide Tommy Collard, who sadly passed away in 2025. They both inherited some of Tommy's intimate knowledge of the Living Desert.

A SNAKE DESIGNED FOR SAND

Peringuey's Adder is small by viper standards, reaching only a maximum of around 35cm, but it possesses an extraordinary collection of adaptations to its sandy home.

It is an ambush predator, spending much of its time buried beneath the surface with only its eyes exposed. Its principal prey are small Meroles lizards, plenty of which we saw emerging after the sandstorm had passed.

One of its most striking features is the position of its eyes. Both are positioned on the top of its head, allowing the snake to remain almost completely submerged while still watching the world above the sand. It is an adaptation reminiscent of the stargazer fishes (Uranoscopidae), which have independently evolved a similar solution to the problem of ambushing prey from below.

Ben followed an unmistakable sidewinding track, ending in an expanse of sand. Then, a tiny flicker of a tongue caught his eye and betrayed the snake's location.

There it was.

SIDEWINDING

Peringuey's Adder's famous method of locomotion is one of the great spectacles of desert biology.

Rather than moving in the conventional serpentine S-shaped waves used by most snakes, the sidewinder lifts sections of its body from the ground and throws them forwards while other sections remain anchored. The result is an apparently effortless sideways movement across loose sand. We got to see this in action!

Despite its superficial resemblance to the American Sidewinder Rattlesnake Crotalus cerastes, the two snakes aren't closely related. Their similar locomotion is a beautiful example of convergent evolution.

Péringuey's Adder has another trick, too. The darkened tip of its tail can act as a caudal lure, potentially attracting prey close enough for the snake to strike.

Backing into the sand using its keeled scales, a Peringuey’s Adder conceals itself (Mike Watson)

LIVING BENEATH THE SAND

The sand isn't merely somewhere to move across. It is also a shelter.

By burying itself, the snake can escape the worst of the desert heat. The sand provides a cooler refuge below the baking surface, while simultaneously concealing the snake from predators such as the Pale Chanting Goshawk, which we saw hanging around nearby. Maybe the goshawk can also recognise the snake’s tracks?

The sidewinder can also exploit the Namib's coastal fog. Tiny droplets of water collect on its body, and by moving its head it can apparently direct those droplets towards its mouth. Under favourable conditions, this can increase its body mass by more than 10%; a remarkable amount of water for such a small animal.

And reproduction is adapted to desert life too. Like many vipers, Peringuey's Adder is ovoviviparous, giving birth to live young rather than depositing eggs externally. Retaining the developing embryos inside the female avoids exposing eggs to the unpredictable conditions of the shifting desert sands.

WHO WAS PÉRINGUEY?

The species was named in honour of Louis Albert Péringuey, a French-born entomologist and naturalist who worked extensively in southern Africa. The snake was described in 1888 by George Albert Boulenger, a Belgian-born zoologist whose name appears on a large number of reptile species.

It was a privilege to see this iconic animal in its natural environment.

Namib Sand Gecko | Pachydactylus rangei (Mike Watson)

NUMBER TWO: NAMIB SAND GECKO

Next on our wish list was another desert specialist that had eluded us during our first excursion in Dorob National Park: the exquisite Namib Sand Gecko Pachydactylus rangei.

This is another animal that has been shaped by evolution for a life among soft sand, extreme heat and almost no rainfall.

Once again, Ben simply said:

"We can find that too, no problem."

And once again, he was right.

He located a tiny daytime burrow, with almost no visible indication of its occupant; just some minute scrapings on the surface of the sand and a tiny hole. He carefully excavated the gecko for us and, importantly, returned it safely under the sand afterwards.

The Namib Sand Gecko is a nocturnal predator and possesses enormous pupils, protected by transparent spectacle scales rather than conventional eyelids. Those enormous eyes are perfectly suited to a creature that emerges to hunt after dark.

Namib Sand Gecko | Pachydactylus rangei (Mike Watson)

FEET MADE FOR SAND

Its feet are perhaps its most obvious adaptation.

The toes are webbed, forming effective little paddles that help the gecko move through loose sand and excavate its burrow.

During the day it can retreat deep beneath the surface; sometimes up to around a metre down; where temperatures are considerably more stable.

As Ben explained to us, loose desert sand contains a surprising amount of air, up to one third by volume in fact. What looks like an impenetrable mass is actually a mass of individual grains with air spaces between them. Beneath the surface, this creates a very different thermal environment from the sun-baked sand above, as we could see using the macro function of our smartphones!

Garnet shadows in the sand. The sand of the Namib Naukluft National Park is full of minute precious stones (Mike Watson)

Ben Bryden shows us how to take a closer look at the grains of sand (Mike Watson)

Details of the garnet shadows are revealed! (Mike Watson)

HARVESTING THE FOG

Like Peringuey's Adder, the Namib Sand Gecko is closely associated with the coastal fog zone.

Water droplets condense on its body and even its eyes, and the gecko can collect these droplets with its tongue.

There is even evidence of social water collection, with geckos licking moisture droplets from one another.

It's an extraordinary example of an animal exploiting a source of water that isn't technically rainfall at all.

A GLOWING GECKO

And then there's the really bizarre feature.

The gecko possesses iridophores in its skin that cause parts of its body to fluoresce a vivid neon green under ultraviolet light, particularly around the eyes and flanks.

Exactly why it does this isn't yet fully understood. Communication has been suggested as one possibility, but the function remains unknown.

Its body is also semi-transparent, another adaptation that helps it disappear against the pale sand.

Another tiny masterpiece of desert evolution.

Namaqua Chameleon | Chameleo namaquensis (Mike Watson)

NUMBER THREE: NAMAQUA CHAMELEON

Although Chantelle was also prevented from finding a sand gecko by the fact that the tell-tale burrow entrances had been obliterated by the sandstorm, she showed her skills by spotting several Namaqua Chameleons Chamaeleo namaquensis from her moving vehicle!

We enjoyed a wonderfully slow-motion encounter with one of these remarkable reptiles.

The Namaqua Chameleon occupies much the same broad desert environment as the previous two species, but it isn't quite as committed to the soft dunes. It is more often associated with rockier substrates and sparse vegetation between the dunes.

On the hot day we encountered them, they were remarkably pale, presumably helping to reflect solar radiation and reduce heat absorption. This also made them just a little easier to spot against the tiny desert bushes.

Sadly, we did not see its most impressive trick.

A TWO-TONE THERMOSTAT

The Namaqua Chameleon can regulate its body temperature asymmetrically.

One side of the animal facing the sun can become pale, while the shaded side remains darker.

It is a remarkable solution to the problem of being simultaneously exposed to and sheltered from intense solar radiation.

The chameleon can therefore use colour, posture and orientation to manipulate its heat balance.

A CHAMELEON THAT DOESN’T LIVE IN TREES

Unlike the stereotypic chameleon, this species is primarily terrestrial.

It therefore has a relatively short tail compared with many arboreal chameleons, and it can move surprisingly rapidly across the ground when pursuing prey.

It certainly retains the famous chameleon's ballistic tongue, but it isn't dependent on sitting motionless and waiting for food to come within range. But it can actively pursue prey, including insects and other reptiles.

And its diet can be surprisingly ambitious: Namaqua Chameleons have been recorded eating lizards and even small snakes, including young Peringuey's Adders!

That creates one of the Namib's most extraordinary predator-prey relationships: a venomous snake that specialises in hunting lizards whose offspring can itself become prey for a chameleon.

MORE DESERT INGENUITY

The Namaqua Chameleon is another inhabitant of the coastal fog zone and has adaptations that enable it to exploit atmospheric moisture. Moisture can collect on its body, with its scales assisting in the movement of water droplets.

It also possesses nasal salt glands, allowing excess salts to be removed in a concentrated secretion rather than requiring the animal to lose precious water.

Reproduction is equally interesting.

The species is oviparous, laying eggs, but the embryos are already very well developed by the time the eggs are laid, representing a step towards becoming ovoviviparous.

Females can also store sperm after mating, allowing them to produce fertile eggs without mating again.

Little goes to waste in the Namib Desert.

Tractrac Chat | Emarginata tractrac (Mike Watson)

NUMBER FOUR: TRACTRAC CHAT

Our fourth Living Desert specialist was rather different from the reptilian trio: the charming Tractrac Chat Emarginata tractrac, a small Old World flycatcher and another characteristic bird of the arid landscapes of western southern Africa.

The genus Emarginata contains three species:

  • Tractrac Chat Emarginata tractrac

  • Karoo Chat Emarginata schlegelii

  • Sickle-winged Chat Emarginata sinuata

The Tractrac Chat is particularly associated with dry, open country, including the Namib Desert, gravel plains, desert scrub and other arid habitats.

A BIRD NAMED AFTER ITS VOICE

The common name is wonderfully onomatopoeic, derived from the "trac-trac" sound of its call.

It is a small, pale, inconspicuous bird, but its tail provides a useful identification feature: largely pale with a contrasting dark tip.

There is also geographical variation in colour. The forms nearer the coast are generally paler, matching the brighter sands and gravel of the Namib, while birds farther inland tend to be browner.

The desert has again shaped an animal to match its surroundings.

Tractrac Chat | Emarginata tractrac (Mike Watson)

DESERT BREEDING

Tractrac Chats usually lay only two or three eggs, and pairs are generally partners for life.

Their nests are placed low down, often on or close to the ground beneath vegetation.

Their food consists mainly of invertebrates; particularly insects such as beetles, ants, grasshoppers, bees and wasps.

They are agile hunters, often making short flights from perches to capture prey before returning.

These birds have learned to treat Chantelle’s vehicle as a mealworm buffet, and approach remarkably closely in exchange for a treat.

Sometimes too close for our camera lenses.

Dorob National Park (Mike Watson)

MINIATURE GEMS OF THE LIVING DESERT

Our time on the Skeleton Coast was brief, but the encounters left a lasting impression.

Four different animals had each evolved their own answer to the same fundamental problem: how do you survive in one of the driest environments on Earth?

The Peringuey's Adder Bitis peringueyi disappears beneath the sand, leaving only its eyes exposed and travelling by sidewinding when it needs to move.

The Namib Sand Gecko Pachydactylus rangei burrows deep into the sand, emerging after dark and harvesting the precious moisture provided by coastal fog.

The Namaqua Chameleon Chamaeleo namaquensis controls its temperature with colour, posture and behaviour, while hunting surprisingly actively across the desert floor.

And the Tractrac Chat Emarginata tractrac less specialised at first glance, makes its living among the sparse vegetation and gravel plains, exploiting the pulses of insects that sustain life in the desert.

And perhaps that is what makes the Namib so compelling. The desert may look empty, but it is anything but lifeless.

We were incredibly fortunate to have Chantelle and Ben, two people who know this landscape intimately, to show us where those hidden treasures were waiting. They know where and how to look.

Without them, we would have driven across the sand and seen a desert.

With them, we experienced a Living Desert.

And for anyone with even a passing interest in natural history, the Miniature Gems of the Living Desert deserves a place on the bucket list.

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