July 2019

JULY 2019

July has come and gone and, although we did have a couple of cold snaps where the temperature at seven am was minus three, it was pretty mild. Almost all July's days were typically blue-sky sunny days like the one above of Mount Anderson viewed from the top of the waterfall near the Miner's Cottage (note the cottage in the bottom left of the picture). I have spent a lot of time in the area where the picture was taken during the month with my team moving in to eradicate the Pine plantations on the road to the Cottage. Exposed life is at it's minimum during this time but I still managed to photograph a bunch of interesting goodies:

Walk the mid to high altitude grasslands in the middle of winter and you will be forced to notice the small bush with yellow flowers dotting the landscape. They are Gnidia canoargentea from the Thymelaeaceae, a family of mostly poisonous plants with floral tubes with sepals attached, represented on the Estate by at least three species of Gnidia, the Mountain Gonna, Passerina montana, and the showy Pom Pom  Tree, Dais cotinifolia. The more common, summer blooming Gifbossie, G. caffra, is poisonous to livestock and well-known to local farmers. Of the 150 species of Gnidia, more than half are endemic to Southern Africa. 

Can you see it? Mostly just the eyes! I'm sure most of you know the Crab Spider, Aniphops of the Selenopidae, from their habit of lying flat on your bedroom wall and running sideways, like a crab, when frightened. In the wild, they are found on and among rocks, under which they take refuge when not active. Unlike the Aranea, who represent more than half of spider species and spend their active and resting time in or around their silken webs, the other group of spiders, the Megalomorphs, of which this is a member, roam freely and hunt for food like a leopard would, sneaking up to and pouncing on it's prey. With a modus operandi like this, concealment is of utmost importance and this little chap has it just right!

This skull and horns are the remains of an Eland who succumbed in the high altitude grasslands near Goudkoppies some time ago. Hollow-horned ruminants, which include all antelope type ruminants from a buffalo, bison, musk-ox to a goat, duiker and a steenbok, form the Bovidae family of ungulates (Mammals that walk on their tippy-toes). What differentiates them from the moose, elk and deer-like ungulates of the Cervidae, the other family in the group (Ruminantia) mostly from the northern climes, is the fact that the bovid's horns are solid bone attached to the skull with a keratinous sheath enveloping them, whereas the Cervids who grow horns (called antlers), grow them for a season then shed them afterwards. The keratin that makes up the horn sheath of the bovids, is made up of the same substance that makes up our hair and fingernails and there are only a few animals that can digest this hard type of protein and they are all insects or smaller organisms, eg: fishmoths, clothes moths and some protazoans and bacterium. In this case, the female Horn Moth, Cetratophaga vastella from the Tineidae, lays her eggs on the horns of a dead bovid and on hatching, the larvae burrow into the keratin and devour the horn sheath. The caterpillars construct tunnel-like cocoons from silk, strengthened with faecal pellets and collectively, these cocoons hang off the horns resembling dirty dreadlocks! Once the pupal stage is complete, a small, pale, slender moth with a pom-pom head emerges. Once all the keratin is consumed, we are left with bleached skull with horns like in the old western movies! 

Brrr! We certainly have had some chilly mornings during the month of July with the mercury showing minus three degrees on at least three occasions. Andries Maphanga, our New Holland tractor operator alerted me to these beautiful grass-blade popsickles at the base of the splashing water tank at Vakatsha (unit 9). 

This Cormocephalus centipede from the Scolopendridae was exposed and disturbed by me when clearing rocks up near Goudkoppies. I always feel guilty when accidentally exposing myriapods (centipedes and millipedes) in the dry season because they are very primitive and cannot retain moisture. Insects, being more advanced, have evolved a waxy substance covering the cuticle that helps retain moisture, allowing them to be exposed during dry times. Myriapods, however, need to make sure they are protected from water loss during these times by hiding in damp and shady areas under rocks and beneath vegetation. If a centipede can manage this consistently they may live to the ripe old age of ten years or more! They are predators, unlike millipedes, and use their antennae to search out any suitable invertebrate prey and when located, it will subdue it's victim with a bite from it's pincer-like "forcipules", forelegs modified into hypodermic stabbing tubes. These forcipules contain venom glands and believe me, a bite from one is as bad as a sting from a scorpion. No human deaths have been recorded from a bite from a centipede although those allergic to bee stings should take precautions against these critters as well. Because of their secretive lifestyle and nocturnal habits, centipedes are not often encountered but this is deceiving because, after spiders, they are the most common invertebrate predator in most terrestrial habitats. So common, in fact, that a vertebrate predator in the form of a snake, the Cape Centipede Eater, Aparallactus capensis, has evolved to prey exclusively on centipedes. These snakes are rather common on the Estate 

In my June blog I mentioned a bunch of succulents that can be encountered during the colder winter months. This was one of them, a Crassula swaziensis. They are pretty common throughout  the Estate at all altitudes in exposed, rocky situations. They are extremely popular garden plants for their hardiness, beauty and ease of propagation from cuttings. The leaves, which form rosettes, are bright green when moisture is abundant and become dark maroon during dry times.

An old abandoned nest of a Drakensberg Prinia, Prinia hypoxantha, pointed out to me by Dennis Jooste of Coch Y Bundhu (unit 1) and situated on the small island in K32. About 130 species of South African bird construct ball-shaped nests but the situation (in rank bush just over a meter above the ground beside water), the knitted construction (as opposed to woven) and the dimensions of the nest suggest it belongs to the Prinia. These little birds are monogamous (male and female stay together for life) and construct the nest together, share incubation duties and both collect food for the chicks, a real team effort. Many small birds that construct ball-shaped nests, particularly waxbills and sunbirds, build their nests in close proximity to the papery nests of social wasps referred to in my previous blog. These aggressive wasp neighbours aid in keeping predators away from the bird's nest. This is understood to be a commensal relationship which means it is one-sided as the bird benefits while the wasp is not positively or negatively affected. But when I handled the nest to confirm it's dimensions, a "foundress" Umbrella Paper Wasp (see June blog) and a couple of  her helpers emerged and flew away. I obviously disturbed them while they were over-wintering within the safety of the abandoned bird's nest. Maybe the relationship between the bird and the wasp is not entirely commensal. Maybe it is sometimes mutual as both parties benefit from the labour of the other, the bird benefiting when the wasp scares a predator away and the wasp benefiting with a safe refuge to over-winter. I did not find the remains of a wasp nest nearby but the scene is many months old...

The dainty corpse of the small Grass Jewel Blue butterfly, Freyeria trochylus, floating in M18, the water's surface tension not allowing it to sink. Before finding himself in this situation, the common male Grass Jewel vigorously defended a territory by perching on an exposed twig or grass stem and attacking and chasing away all other male Grass Jewels that entered the area. while females were herded within the territory until they were mated with. The females then searched out the larval food plant, Indigofera sp. (and in the lowveld, the beautiful String 'o Stars, Heliotropium stuedneri), and laid an egg on it so that the larva would have a ready food supply upon hatching. Lying on it's back with head turned, all I needed to see was it's tongue lolling out!

Another beautiful flower blooming in the winter time is the Starry Strawflower, Helichrysum spiralepis, found in medium to high altitude grasslands throughout the Estate.The small bushes are attractive both when the flower is budding with it's dark maroon buds (R) and once it has opened it's pale lemon flowers (L).

A minature geranium, Pelargonium dispar, showing different stages of leaf development. The green leaves in the rear are new leaves emerging while the beautifully coloured leaf is an old one on the way out. Also visible are a few that are dead already The striking flower is that of a typical Pelargonium and can be found in and around forest fringes in late summer and autumn. This small individual is completing it's first year of growth and will flower for the first time at the end of this approaching summer.

While having lunch one day high up on the Rock Kestrel Trail, I looked down to see this caterpillar spinning a web of supportive strands of silk to house it's pupa (chrysalis) in the corner of a broken rock. After hatching on it's larval food plant, the ravenous new larva of the butterfly first consumes it's egg shells before getting tucked in to the food plant. When it has eaten until it's skin is so stretched that it may burst, the caterpillar will shed it's skin and emerge with a looser skin and a bigger head and the first thing it does as it enters it's second instar is eat the discarded skin of it's previous instar, a great recycler!. This process is repeated until the end of it's fifth and final instar when it will leave it's host plant and find a suitable spot to enter it's pupal stage. This is where the above caterpillar finds itself in the photo. Once at has secured itself sufficiently, it's skin will harden and the caterpillar begins the pupal process where it's body liquidises and reforms into an adult butterfly that will emerge, mate and repeat the process. I think this is the caterpillar of one of the Whites from the Pieridae. 

In my April blog, I posted a photo of a Ladybird beetle eating an aphid and spoke about how important they are as predators of aphids. Above is a photo I took of an winged aphid, probably a rare male that hatched at the end of autumn. I say rare because it is the only time we get to see the male as he searches for batches of eggs to fertilise. During the spring and summer months, the female, after reaching maturity within a week of hatching from her egg, will bare two to four young parthenogenetically (meaning as clones without fertilisation by a male) per day! Thank goodness for the Ladybird beetle and the Lacewing larvae (Check the May blog) because , without predation, the number of parthenogenetic offspring from one adult female and her offspring will be around 210 to the power of 15 in only one year! That is an unimaginable number!! Only at the end of the season do they bare male offspring. In fact, many species of Aphid in the world do not ever produce males and breed only parthenogenetically. On the day that I photographed this individual they were everywhere, getting tangled in my hair and beard and getting into my ears. Bring on the predators!

Many of you would have noticed a breeding herd of Greater Kudu, Tragelaphus strepsiceros, hanging around the central area since the fire almost a year ago. These two youngsters, photographed by the water tanks for Otter's Rest (unit 10) and Elsmere (unit 11), are two of four that were born on the Estate during the summer. Kudus certainly occur here although usually only for short periods of time before moving back to the more wooded habitat found in Nooitgedacht and Rivendel and sometimes big bulls stay here more permanently. But this is the first time that I have noticed them, as a breeding herd, spend so much time here. I think this is because of their habitat shrinking in our neighbouring farms due to the fences that have been erected in Rivendel over the last few years. I don't think the situation is critical because if they were too stressed about it they wouldn't breed so prolifically. And it is certainly great to have them here. Welcome!

The days are lengthening and warming up as winter fades and spring approaches. And as you can see, no matter what time of year you come there is always a lot of life here. Come and indulge. See you then...