A Couple of Short September Excursions
Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"
September in South Africa is when Springtime starts! But in practice, this is still the very end of winter. The temperatures are rising, the days are pleasant, the nights remain cool to cold, but it is still very, very dry. The first drought-relieving rains usually start only in mid-October or even November. So far it's been a typical September; the closest we've come to rain was a few nights ago when there was light thunder, but nothing more. At least in my garden I've been giving a bit of water to some of my plants, and my garden skinks and geckoes eagerly come to lick up a few drops. The critters out in the wild are not so fortunate.
We're gearing up for explorations here for the new season, and so my reptile-hunting friend Ruan Stander, our local zoologist Professor Derek Engelbrecht, and I, were out on a couple of recent outings. The first was to the Blouberg Nature Reserve. This is a large (around 10 000 hectares) nature reserve encompassing the northern part of the Blouberg mountain. More like a small mountain range than a single mountain, it is an ancient massif separated from the Soutpansberg Mountains to the East, rising to over 2 000 m/6 500'. The northern parts belong, ecologically speaking, to the dry Limpopo River Valley. The mountain itself catches much more rain, the higher slopes being covered in moist grassland and the southern slopes having extensive evergreen forests. The plains to the north, however, have regions of deep desert sand and is generally covered in dry woodland. The trees you see here are worm-bark false-thorns, Albizia anthelminthica, a drought-tolerant species that was copiously covered in wispy white flowers at the time. But they still looked quite scruffy. I hope you get the idea of how dry everything was.
We were seeking reptiles! These tough little critters with their scaly skins do well in dry environs. They creep into crevices or burrow beneath the soil to stay cool and avoid desiccation, and come out to bask in the sun whenever they need to warm up. Derek especially wanted to find some of the fascinating burrowing species of our region, such as legless or burrowing skinks. The skink family is amazing for how 'easily' many of its members have lost their legs. Among the dwarf burrowing skinks you will find every configuration from species with four fully-formed legs and feet, to some with reduced legs with just a couple of toes per foot, to some with just tiny stubs for legs, or just hind legs and no forelegs, and some with no sign of legs at all. People often mistake the latter for snakes. But no skinks are venomous. They're harmless except to the small invertebrates they feed on.
So there we were, turning over rocks and digging in accumulations of leaf-litter seeking burrowing skinks. Sadly, this time we didn't have enough time, and the little crawling critters eluded us on this day. But we did not come away empty-handed. Here are some of the little reptiles we did find.
First, we did find some skinks, though not burrowing ones. This is a Striped Skink, Trachylepis striata. It is one of our most successful skink species, abundant in the hot, low-lying, north-eastern savannahs of South Africa. It can grow to over 20 cm/8" in total length. Since it is so adaptable, you can find it on the ground, on rocks, and even in trees. It also can make its home in gardens and around human habitations. The skinks in my own garden belong to a closely-related species, the Montane Speckled Skink, Trachylepis punctatissima, which is equally successful in more high-lying, inland regions.
Another very successful group in South Africa is the Cordylid family, which includes girdled lizards, dragon lizards, flat lizards and more. Here you see Jones' Girdled Lizard, Cordylus jonesii. You can clearly see how the sharp-pointed scales are arranged in neat girdles around the body, limbs and tail, a protective spiky armour. This species is found also in warm to hot savannah in the north-eastern corner of the country. It shelters beneath loose bark, in hollow, rotten logs, or in rock crevices.
South Africa in addition abounds in geckoes. Several species are found in the Blouberg region, but on this day we found only two. First here is the robust Turner's Gecko, Chondrodactylus turneri. Its skin is soft, as in most geckoes, but has these rounded wart-like knobs all over it. Its head and eyes are large, its pupils cat-like slits. Like most geckoes, it is nocturnal. You can find it on trees, rocks and sometimes around houses. We found ours sheltering on tents in a tourist camp! We put one on the ground to take photos. This gecko can exceed 20 cm/8" in length, and occurs in both the north-west and the north-east of our country.
Another one we found on the tents was the Tropical House Gecko, Hemidactylus mabouia. It does occur in the wilds around here as well, and we've found them on baobab trees elsewhere. But this delicate gecko flourishes around humans, frequently being inside the house where it does great service by catching mosquitoes and other bothersome insects. This is an amazingly widespread species, ranging along the Atlantic and Indian Ocean coasts of Africa, and also along the east coast of South America and in the Caribbean Islands. In addition, it has spread wide all over the warmer parts of the world thanks to being able to live with humans. Originally only in the lowlands, it has spread inland in South Africa and can be found in all our large cities now. In nature, it inhabits trees and big rocks.
That was that for the day at Blouberg. A few days later I was out with Derek on a different kind of excursion. We were surveying a population of rare plants not far from our home town of Polokwane. The plants at issue, Euphorbia clivicola, are known only from three populations: one in the Percy Fyfe Nature Reserve, one close to my own home on Radar Hill, and one at this place we went to, close to the village of Dikgale. The Percy Fyfe population has probably gone extinct. The other two populations are both under severe pressure. The Radar Hill population is suffering from encroaching human residences, plus alteration of the normal wildfire regimen – because of the people living there, natural grass fires are suppressed and the veld is being taken over by trees and shrubs so that the Euphorbias are shaded out. The population has dwindled from thousands to, at last count, a couple of hundred. The Dikgale population seems to be least at risk: there is still extensive fairly undisturbed habitat in the region. But it suffers from overgrazing and, at the time we went, drought. The veld was extremely dry, in fact desert-like. All plants we found showed signs of extreme drought stress.
Actually we found two different forms of Euphorbia! I was confused when I saw the first plants, since they looked to me not like Euphorbia clivicola but like a relative I know from around the Makgeng area to the south. We found a great many of those, all of them looking very poorly. Then we suddenly came upon ones that looked like the proper clivicolas we knew! Here you see a photo of one of the largest and finest ones we found. As you can see it is hardly at all 'green' and its stems are shrivelled-looking (the round, reddish leaves at the upper right corner belong to a different species, Crassula swaziensis). Under good conditions, clivicola has plump, finger-like, fresh green stems growing densely together in a low, spreading, cushion-like mass. The other Euphorbias we found, had thinner, longer stems, more sparse and not as densely arranged. They tended to be red or purple as a result of heat and drought stress. I later got info about them from Bronwyn Egan our local botanist at the University of Limpopo. Apparently 'science' knows of the presence of both species at Dikgale, but the ones that are not clivicola, are not yet properly described. They, with the ones around Makgeng, likely belong to a new species. I will do some surveying of my own of this form to determine its distribution since I know of ones from well away from the places where the documentation Bronwyn sent me mentions them as occurring.
Derek did a lot of measuring of Euphorbia plants for the sake of recording scientific data about them. I again stress that we know hardly a thing about these plants. This is actually the situation for a great many of our local plant species. It is the norm rather than the exception for a plant species over here to be found only on small patches of land. This makes them extremely vulnerable. A farmer ploughing a few acres may end up destroying an entire species the natural habitat of which was entirely confined to that area. Humans have immensely destructive habits and severely affect natural regions wherever they go. The population of clivicola in the Percy Fyfe reserve was officially fully protected, but went extinct because the reserve management focused on the needs of the large mammals in the reserve rather than on the plants. I will try to get the full story about why they went extinct but it might have again been due to alterations in the fire regimen, as well as perhaps overstocking the reserve with large antelopes, which trampled and ate the small plants. In the remaining two populations, the stress factors affecting them will be different. So far we don't know what animals pollinate the euphorbias, we don't know how effectively they're setting or distributing their seeds, we don't know what the ideal conditions are for their seedlings to establish themselves, we don't know their optimal temperature and moisture needs, we don't know how long-lived the plants are, and consequently, we don't fully understand why they're dwindling and suffering and what we can do to give them a hand. I must stress that every species in Nature is fascinating in its own right, and we can't just 'let' any species knowingly go extinct, no matter how 'obscure' it might be. These euphorbias may not at all be known to the public, and hardly anybody will even know when they go extinct, and yet it will be an irreplaceable loss and a diminution of the richness of the natural heritage not just of South Africa but of the entire world. All species deserve to live, and every single one of them has a wealth of things to teach us, scientifically, about the potential of life on our planet. Plants contribute to the uniqueness, specialness and magic of every location they grow in. These clivicolas for instance have been a joy to me ever since I first stumbled upon one in the wild, not even knowing then just what it was. I'm going to do everything in my power to try to ensure that they remain a part of the wonder of the wild places around my town.
Though we were mainly conducting a plant survey, Derek is very interested in birds also. We were amazed to find up there on the hill a population of Shortclawed Larks, Certhilauda chuana! These larks normally live on the plains. They're rare and confined to only a few spots in South Africa and Botswana. They occur in our local nature reserve, but the population there has decreased severely, again as a result of bush encroachment due to a bad fire regimen. Funnily enough, the larks now flourish more and more outside of protected areas, where human communities heavily impact the veld by cutting down trees for firewood. The larks like open, dry areas with short, sparse grass and very short, stunted trees, exactly the sort of habitat that results from humans over-utilising the wood and from goats, cows and donkeys trampling and overgrazing the veld. The larks find their mostly invertebrate food easily in such open land, and do their territorial singing and low display flights from the tops of bushes and low trees. Many tall trees would interfere with the visibility of these flights to larks far away.
Up on the hill our unexpected larks treated us to a spectrum of different kinds of calls. Derek wanted to catch one. He had a fiendishly clever strategy. First there was the trap. It looked a bit like a meat griddle, but with a fine mesh of fabric threads. It works a bit like a bear trap. In the centre there's a sensitive thingy that springs the trap. Derek put a nice juicy meal worm in the centre to attract the lark. He also put a speaker nearby and from it was broadcasting lark territorial calls. The idea was to attract the lark to the trap, making it think there was another lark trying to challenge it. Then the lark would (hopefully) notice the nice juicy meal worm and hop into the trap to take it, springing the trap and so catching it. Derek set up the trap, we retreated a distance and waited. Soon enough a lark was showing interest. It was interesting to us also, because this lark walked rather than flew towards the trap. It walked a great distance in fact; it could have covered the same ground in a few seconds if it flew. But it didn't. Perhaps the larks up here want to remain inconspicuous due to all the humans being about. Skulking about the rocks and bushes, apparently very wary, our lark was very hard to see as it walked closer and closer to the trap, and eventually perched nearby. But it didn't go into the trap, nice juicy meal worm or not. After a long time waiting for the lark to take the bait, Derek decided to give up. But not completely. We found some other larks a short distance away and Derek again set up the trap. This time it worked! The lark stepped on the trigger-thingy, springing the trap, and was caught! We rapidly got it out and Derek took a bunch of measurements, still with the science-data-collection mindset. He put a ring on the lark's leg and released it; for once, it flew rather than walked off. Ringing studies can tell us a lot about birds, mainly how they move around and how old they get. Derek is on a perpetual project monitoring these short-clawed larks. Here finally you can see a photo showing the lark's comparatively short claws and toes. This does indeed seem to signify a bird much better suited to walking than to perching.
The larks and the euphorbias share the same plight. They're 'obscure' species that Joe and Jane public knows nothing about. Even 'science' knows hardly a thing about them. They have these small areas of distribution that mostly lie outside of protected areas, in the midst of burgeoning human populations. They're a nightmare to figure out proper conservation measures for. For now, they are hanging on, but small changes in how the humans live around them may change their environments so much that they could vanish in an instant.
Indeed, a very large portion of the biodiversity of Planet Earth shares a similarly perilous plight. They are small and unknown critters living on the fringes of wild country that are rapidly shrinking and fragmenting to make way for human settlements, farms, roads, industries, mines, and what have you. Just setting aside some wild land here and there to protect as a nature reserve is not enough. We need to be thinking big, and thinking ecologically. We do need science. We need to figure out what these species need. We can't go on thinking that humans, and only humans and their needs, matter. Thinking sustainability means we need to think about sustaining the biodiversity, the biological richness, of the planet as a whole. That includes EVERYTHING. Sustainability doesn't mean seeing how much damage the planet can sustain while still sort-of hobbling along for the moment. We can't go on depleting the living world and still expect not to have to pay anything for that in the end. We can't go on thinking that the other things on this planet have nothing to do with us. Planet Earth is distinguished from all others in the solar system by the life that it sustains. The life of the planet IS the main feature of this planet, and it is a self-sustaining system. It's the most complex, interesting and beautiful phenomenon that we know of, in fact more wonderful than we can imagine. And we're a part of that. We arose out of the wild, living planet. Nature is OUR nature. Destruction of nature is self-destruction. The ignorance of the public right now of how much they are a part of and belong to the life of the planet is a kind of insanity, an extreme spiritual poverty. No amount of technology can make up for that. But what can one do? This is what I'm trying to do, I'm just trying to raise a bit of awareness about biodiversity and ecology in my writings. We can't recruit every human being to this project, but even just a few thousand people working all over the world can in fact accomplish a lot. The word needs to get out. If we can deflect just a tiny fraction of the trillions of dollars spent every year by humans on utter nonsense, there's a lot of good that we'll be able to do. Eventually, just maybe, Joe and Jane Public's eyes will open.