Have a good look at the pictures below and see how many animals you can correctly identify from the shape and structure of the front feet as depicted by the photos. These animals all occur in Pilanesberg.

Good, let’s see how well you know the animals by looking at feet only.

Animal A
A plains animal that is quite common in most of the Northwest Parks. The tracks are on average 100 mm in length. The animal has a characteristic track in that the hooves of the front feet form a rather large opening in front. Another feature is the somewhat asymmetrical shape of the spoor or track as the one hoof is very often positioned slightly more forward than the other, which is also noticeable in the photo. A final feature to note is the blunt and rounded tips of the hooves (Blue Wildebeest).

Animal B
This animal is more active at night, although often seen during the day, especially in winter. The front track is on average about 85 mm long. Characteristic features include the definite claw marks in the track, the trailing edge of the hind pad that is slanted, the front toes that are not aligned and the close proximity of the toes around the hind pad. The trailing edge of the hind pad has two lobes and the leading edge one lobe. Very often hair marks are noticeable around the tracks in soft sand (Brown Hyena).

Animal C
An animal of the plains areas with legs and feet adapted for speed. The front track is on average 92 mm long. This is an easy identifiable track because of the characteristic toe-pad or frog that is protected by a well developed hoof. These animals walk on the first digit of only the third toe, i.e. they so to speak walk on the tip of one toe, which is a feature of horses, donkeys and zebras (Burchell’s Zebra).

Animal D
A large (120 mm), spherical front foot with well developed dew claws (see in picture), that often show in soft sand as two depressions behind the track. The tracks are sometimes confused with that of eland, but they are larger and more rounded (Buffalo).

Animal E
The tracks of this animal do not resemble that of any other species and the large size (230 – 280 mm) and four rounded toes on each foot make it easy to recognise. This animal has a wide straddle (distance between feet on either side when walking), giving a characteristic ‘middelmannetjie’ to the paths of these animals (Hippo).

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So often one hears people talk about False Marula trees in places like Pilanesberg. The fact of the matter is there are not False Marula trees in those parts of the world. So, what then is a False Marula, where do you find it and how does it differ from a true Marula?

False Marula trees do not occur in the north western parts of South Africa. The tree that people so often refer to as a False Marula in these parts is actually the Live-long that belongs to the same group or genus as the False Marula. Both trees belong to the genus Lannea, which refers to the dense, woolly hairs that cover the young parts of the plants.

Both the Live-long (Lannea discolor) and the False Marula (Lannea schweinfurthii) belong to the same family as the Marula (Sclerocarya birrea), namely the Mango Family (Anacardiaceae). These three trees are characterized by the following common features:

• Medium to large deciduous trees in bushveld
• Leaves with a watery latex
• Berry-like fruits called stone fruits or drupes
• The strong resinous smell of the crushed leaves
• Male and female parts on different trees, a condition referred to as dioecious.
• Compound leaves, once divided with a terminal leaflet, which means that the ordinary leave is subdivided into smaller leaflets of unequal number.

A live-long can be distinguished from a Marula in that the leaflets of the live-long have very short stalks and the leaflets are clearly discoloured being dark green above and silvery grey below. The leaflets of the Marula have much longer stalks and are of an even greyish-green colour on both sides. The leaflets of the Live-long are also much larger than those of the Marula. There are 3-5 pairs of leaflet per leaf in Live-long and
3-7 pairs in Marula. The bark of a Live-long is dark grey and does not flake off in round or square depressions like that of the Marula. The fruits of the Live-long are purple compared to the yellow colour of the Marula fruits when ripe. The fruits of the Marula are also significantly larger; 30 – 35 mm in diameter compared to the 10 x 7 mm fruits of the Live-long.

The actual False Marula (Lannea schweinfurthii) is restricted to the warmer northern and north-eastern parts of the country. The bark flakes of in much longer strips than in the Leaves of the Live-long Marula leaves Marula although the stems of both trees have a mottled appearance because of the flaking off of the bark. The leaves differ from that of the Marula in that it also has leaflets with very short stalks. The leaflets are also larger with a darker shiny green appearance. There are fewer leaflets per leaf (1-3-pairs) than in either Live-long or Marula trees. The fruits of the False Marula are oval shaped, dark red when ripe and borne in long clusters.

All three tree species are typical bushveld trees that provide ambiance and atmosphere to the Bushveld Savanna. In autumn the hillsides of Pilanesberg are painted in warm yellow-orange colours just before the leaves of the Live-longs are falling.

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Driving through large stands of beautiful grassland in some of our reserves and not seeing any or very few animals, you must have asked yourself “Where are all the animals?” Well, there might be good and obvious reasons for not seeing any of the grazers on that apparently appetising grassveld, reasons that we as human beings do not always consider or even understand as we prefer not to eat grass!

Just as trees and other plants have evolved various means to protect themselves against browsers (leaf feeders), so have grasses developed methods to reduce grazing and protect themselves against grazers (grass feeders). Although grasses and grazers have evolved and coexisted for millions of years, their relationship is not one of compliance and acceptance, but rather of tolerance and adaptation. Grasses are constantly evolving new strategies to reduce over-utilization by grazers while grazers develop new approaches to deal with grass ingenuity.

Grasses are considered palatable when they taste nice, have a high protein value, produce a lot of leaves and are digestible. By changing these factors through structural and chemical adaptations, grasses can reduce their palatability and become less acceptable to grazers.

Structurally grasses defend themselves by becoming very fibrous, especially towards the end of the growth season, which make them less digestible. Most grasses contain microscopic silica crystals within the leaves, which effectively wear down the teeth of grazers. It’s like chewing bubblegum containing minute sand grains. In order to overcome this problem grazers have all developed high crowned teeth. The presence of hairs on the grass stem and leaves is another effective deterrent against insect grazers such as locust. To these “goggas” those hairs on a grass plant are what the thorns of a thorn tree are like to mammal browsers.

Chemical defense relies on the production of aromatic oils and other bad tasting chemicals that grazers, especially mammal grazers, find unacceptable. Good examples are Pinhole grass, Stinking grass and Turpentine grass.

Other important factors to consider are the structure and composition of the grassveld. Just as we like variation in what we eat, so do animals and for that matter grazers. Monocultures (large grass stands of a single grass species) are not favoured by animals and they tend to avoid it even if the grass species is palatable. Animals are also very vulnerable to predation in tall grasslands and they spend as little time as possible in these areas.

So, next time you drive through those grass plains in one of our beautiful nature reserves not seeing any game, have a good look at the grasses while considering all the factors mentioned above. It just might give you an idea where else to go looking for those elusive Tsessebe, Red Hartebeest or Blue Wildebeest.

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Those “pesty” little things that play havoc in my garden and house and that should be exterminated at all costs? No, hang on! Not so fast with the extermination idea! Well, at least not in the natural environment. These little creatures are the pantries, excavators, cleaners, decomposers and
fertilizers of nature and deserve a bit more respect, attention and admiration.

So, what are termites then? For a start, we know that they are insects. Some people refer to them as “flying ants” or “rysmiere” and Eugenè Marais, famous author and naturalist, even referred to them as “white ants”. Fact of the matter is that they are not even remotely related to ants and are evolutionary speaking, closer to cockroaches. Structurally they differ from ants in not having a “waist” between the abdomen (hind body) and thorax (breast). They also have straight antennae (feelers) and not the knee-like bend antennae of ants. Unlike ants, termites have a life-cycle which does not include a pupa stage. This is described as incomplete metamorphosis (hemimetabolic development) compared to the complete metamorphosis (holometabolic development) of ants. Just like ants though, termites are social insects that cannot exist and function as individuals.

Well, so much for the technical detail. Termites are considered a very ancient and primitive group of insects, which existed in their present form for more than a hundred million years. They are all herbivorous, eating wood or other dead or green plant material. Except for a few, most termite species do not possess the enzymes to digest the cellulose in plant cell walls. In order to obtain the energy stored in these chemical compounds they have to rely on other micro-organisms to do it for them. For this purpose some like the harvester termites (Hodotermes spp.) lodge microscopic unicellular organisms called flagellates, in their intestines. Others (Macrotermes and Odontotermes spp.) make use of a fungus that they cultivate to perform this function outside their bodies. It is these fungus-growing termites that are responsible for the so familiar structures that are erroneously called “ant-hills”, but which are in actual fact termitariums or termite mounds.

In the natural world a termitarium is without a doubt one of the most remarkable wonders of nature and in structure and function exceeds any of the so-called technologically advanced engineering endeavors of the human race. They have been referred to as “castles of clay” and indeed that is what they are with king and queen, workers and soldiers, all performing a specific function in maintaining this encapsulated society. The most intriguing thing is that all happens in complete darkness. A termitarium is designed in such a way as to create just the right micro-climate
and conditions for the comfort and well-being of the termites and for the fungal gardens that they grow and maintain. The fungus serves not only as a food source, but also as an air conditioning unit that regulates the temperature and humidity inside the termitarium. It generates heat as it grows and absorbs surplus moisture, which is released back into the air when the humidity inside the nest falls below a certain level. Termites can tunnel as deep as fifty meters to find the water that is necessary for maintaining the atmosphere inside their nests.

With all their excavations and construction activities the termites continuously bring nutrients up from deeper down so that the soil in and around the termitariums becomes quite fertile. This is eminent from the variety of tree species that grow on these old termitariums. Termitariums are often covered with blue buffalo grass (Cenchrus ciliaris) which is a good indicator of fertile soils. In places like Pilanesberg for example, the fungus growing termites prefer areas underlain by “ou klip” The mound of a fungus-growing termite (ferricrete), which forms an impermeable layer just under the soil surface where water accumulates in depressions making it more accessible to the termites for collection and transportation back into their nests.

Over many years the continuous activity of termites collecting coarser soil particles, minerals and water from deeper down and transporting it to the surface, a process known as “bioturbation”, has effectively contributed in forming a clay rich layer over the ferricrete. This process contributes in dismantling the hard impervious layer of “ou klip” under the termite mound, forming a so-called “soft spot” with deeper soils allowing trees and shrubs to thrive on these areas. This has created the so familiar tree patches associated with the termite mounds that can be seen all over the Bushveld landscape.

Termites and their termitariums play a significant role in the ecology of natural ecosystems. Their main contribution to the ecology of this beautiful reserve is as a source of food. Many insectivorous birds feast on the termites that also form the main diet of the large, black Matabele ants and mammals such as aardvark and aardwolf. In the dry season the sweeter grass that grows on these termitariums are eagerly sought after by grazing animals in need of nutritious forage. Red hartebeests and tsessebe often use the termite mounds as lookout posts and central points in their territories. It is home to a myriad other organisms, ranging from invertebrates to reptiles and mammals. Water monitor lizards lay their eggs in the termitariums where they become safely sealed off and develop at an almost constant temperature and humidity. The ideal incubator! Predators, especially cheetah, often climb up on them as a vantage point to spot potential prey. Elephants and rhinos use the termite mounds as rubbing posts, sometimes completely demolishing them, and in so doing return the concentrated nutrients to the soil.

Although these little insects are generally not visible, their mounds certainly advertise their presence. So, next time you drive past one of these wonders of nature, consider the fact that our natural world probably would have had a completely different ecology and landscape if it weren’t for these little insects.

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