WINTER 2023

 WINTER 2023

Winter is over, and what a strange one it was. It was quite mild, even considering the atypical snowfall. It was also the wettest winter since I have been here on the estate, with just under 10mm falling in June, and between 27mm (Majubane) and 44mm (Central) falling in July, and a single 5mm rainy day in August. But between these showers we experienced many overcast days. The end of July also marked the end of the 22/23 rainy season. We had an above-average rainfall with an average of 1008mm precipitation over the estate (the average over the last eleven years is 910mm/annum). That ranged from 1136mm over the central area of the estate, 1070mm in the north, 1024mm in the east, 949mm over the western part of the estate and, the lowest, 864mm over the southern part of the estate.

The highlight, of course, was the 12,5 centimeters of snow that fell over our mountains on the 10th of July! The photo above shows Mount Anderson (left) and the watershed that runs south of it, including Mount Formosa, with the puffy cloud over its peak, covered in snow! What fun it was! I think it was only the second time in Finsbury's history that it snowed.

Besides the excitement of the snowfall, there was much else that provided me with entertainment in the usually dull winter months. Below are some of those that I managed to photograph:

If you refer back to my EARLY SPRINGTIME blog posted on September 28 2021, I featured a little blurb on a Grass Aloe that I had photographed. Well, that specimen was a late-blooming Heath Grass Aloe, Aloe chortolirioides, as I had suspected. Afterwards, in the blog, I mentioned how I received an email from one of the Mpumalanga Parks' botanists, asking if I had encountered the rare, near-endemic (meaning it only occurs in a very small area) Mount Anderson Grass Aloe on the estate, to which my reply was in the negative. Mainly because the known Mount Anderson Grass Aloes Occured on the east-facing cliffs below Haartebeesvlakte, which is at 1700masl or less. 

Well, this is a photograph of the near endemic Mount Anderson Grass Aloe, Aloe andersonii, taken by Louise Twiggs from "The Crofts", unit 19, some time ago. She had posted her photos on iNaturalist and it was duly identified as the Heath Grass Aloe (an easy mistake to make from a photo, since the altitude and situation of the plant supported the Heath Grass Aloe). Then, being a very accomplished watercolour artist, Louise decided to paint the Aloe (check out some of her stuff on www.louisetwiggs.co.za). While in this process, a friend and fellow aloe lover, identified it as the rare Mount Anderson Grass Aloe and had this confirmed by Ernst Van Jaarsveld himself, the SANBI botanist that described the aloe only as recently as 2014!

Since this delightful discovery, I have scrutinised my grass aloe photos and found that I too, have mistaken the Mount Anderson Grass Aloe for the more common Heath Grass Aloe before. Now that I have encountered both species, it is easier to tell them apart, so I won't be making the same mistake again. The Heath Grass Aloe has much slimmer, longer leaves than the Mount Anderson one, and, importantly, ten or more white, papery bracts on the peduncle (stem holding the flowers), as opposed to only six on the Mount Anderson Grass Aloe

So that's another near endemic found only on Mount Anderson and immediate surrounds. I think that makes it three, including the Mount Anderson Everlasting, found only between Mt Anderson and Mt Formosa (refer blog of August 2020); and the Staerkers Disa, found only on the summit of Mt Anderson (refer to my blog: New Orchid Species, posted on Sunday 19 February 2017). Exciting stuff, thanks Louise!  

I was going through my files recently (a sensible activity when it is very cold out) and opened the file of as-yet-unidentified moths that I have photographed here on the estate, a large file indeed! Large because there are over seven thousand species of moth so far described in Southern Africa, and a big part of those occur here at Finsbury in these open grassland, riparian bush and forest biomes. When I succeeded in narrowing the above moth down to the Emperor moth family, Saturniidae, I paged through the file I have of caterpillars and cross-checked those adults, on iNaturalist, with this moth, and Viola! Got a match and got it confirmed. I love it when that happens, having both pictures, taken here on the estate, of the larva and adult of a moth or butterfly species. Because, if you think about it, if there are seven thousand species of moth in Southern Africa, then it would be the same as having to learn fourteen thousand different search images to cover the identification of all the species (since the larva and adult look so different to each other). To make it even more mind-boggling, all of those species have multiple instars as a caterpillar (when they shed their skins as they grow), where the majority, of those species, take on a completely different appearance in their following instars. So, in this instance, in the caterpillar stage, which has five instars, this individual caterpillar will look like five different caterpillars before it pupates and comes out as the adult moth!

These are the caterpillar (larva) and moth (adult) of the Cabbage Tree Emperor moth, Bunnaea alcinoe, and the photos do not do their size justice. The bold and dazzling caterpillar is a whopping seven centimeters long and one-and-a-half centimeters thick! It's actually heavy in one's hand. The moth is also enormous, with a wingspan of sixteen centimeters, very hard to miss when attracted to your artificial lights at night. The moth in the photo is clearly that of a male because of his spectacular golden antennae that are brush-like (check my spieel on Lepidopteran antennae in my blog of December 2019), which means he is still small compared to the female, who almost doubles his size.

The larva hatches from its egg that has been glued to a leaf on its host tree, in this case a Common Cabbage tree, Cussonia spicata, like the massive one, up against the cliff between K23 and K24, that Lone Tree cottage (unit 3) is named after. The larva consumes massive amounts of cabbage tree foliage during its five instars, which take well over two months to complete, before constructing a silken cocoon around itself and entering its pupal stage. If this is in the late spring or summer months, then before three weeks is up, the adult moth emerges from the cocoon, and with completely undeveloped mouthparts, only has three to four days to find a mate and breed before it dies of starvation.

If it is a male like this one, it uses its antennae, which are extremely sensitive, to pick up pheromones that are emitted by a female as far as two kilometers away! Once alerted to the smells of a female, the moth zigzags into the wind on the path of the female until, hopefully, he finds her. I say hopefully because the biggest threat this moth faces in the darkness when it is active, is its life-long, mortal enemy, the insectivorous bat!

Now, if you go back to my blog of NOVEMBER and DECEMBER 2020, I featured an article on a Tussock moth and mentioned how they can hear when a bat is homing in on them with echolocation and then take evasive action. I also mentioned that there are moths that can actually produce clicking sounds similar to those emitted by bats during echolocation, and thus confuse the bats. Well, this moth, the Cabbage-tree Emperor, has gazillions of minute, overlapping scales with pitted surfaces that absorb the soundwaves emitted by bats, acoustically camouflaging itself from discovery. Extremely useful for such a large moth.

I found this caterpillar, resting with at least a dozen buddies, in the cold, on a Common Waxberry tree on the Razorback road in the middle of winter. Clutched to the leaves and branches. Like the Cabbage Tree Emperor caterpillar and moth above, it is also from the Emperor moth family, with a caterpillar just as massive.

Now, normally, a caterpillar hatches from the egg and eats and grows until it enters its pupal stage, and then emerges as an adult. This cycle is usually completed several times during a single growing period (season), allowing the species to produce a few generations per season. Usually, the final generation of the season will enter a period of diapause within the pupal stage, allowing it to overwinter within the safety of the cocoon or pupal casing. Then, when the temperature increases, and or the daylight hours increase, the adult insect will emerge and continue with the cycles for another season. Sometimes the timing is not as perfect as that, and an underdeveloped caterpillar may have to enter a period of diapause before the pupal stage if the season changes before it has a chance. This must have been the case with these caterpillars.

The disadvantage of this situation is that the caterpillar is not protected as well as it would have been had it been within the cocoon enclosure (mud, in this case), and a hungry predator may just find it... If I was surviving in the wilderness and I encountered these caterpillars, I would have scoffed them down and been very happy with myself. Firstly, they are the caterpillars of the Emperor moth Gonimbrasia bubo, very closely related to the Mopane worm, G. belina, meaning they are most likely good and edible, although I would cook them to be sure. Secondly, they are huge! There's lots of yummy nutrients to be had from that massive body. There were at least a dozen of them hiding amongst the leaves of the tree, surely enough to be an entire meal on their own. 

This is a Finger-net Caddisfly in the Philopotamidae family in the Trichoptera (hairy wings) order of insects. Together with the Lepidoptera, butterflies and moths, and an extinct order, they form a superorder with a common ancestor. One of the shared characteristics is the presence of dense hairs on the wings, modified as scales in butterflies and moths. This species, in the Chimarra genus, is only a half a centimeter long but pretty common, so it is easily overlooked. 

Like butterflies, they are active during the day and can be seen doing a little walk-dance in a figure eight pattern on the substrate. Very busy little things. Never stand still for a moment. I have tried to find out why they perform this little dance continuously. I first thought that it must be gathering food but, according to all the literature I have managed to find, the adults of these insect either don't feed at all, or they feed on a liquid diet, like nectar, because their mouthparts are underdeveloped. I will find out one day...

Almost all the research I have conducted has been concentrated on the long-lived larvae. The larvae are aquatic, like Mayfly and Dragonfly larvae, and so form an important part of the river ecosystem. Mainly by feeding on animal detritus and being an important food source for fish, like trout. Dry flies used in fly fishing are often made to resemble an adult Caddisfly, commonly known as "sedges", so most of you should be able to recognise them. The larvae are predatory and spin an elaborate net that they hold against the current to catch bio detritus. Amazingly, and hard to believe, these nets can contain a kilometer long strand of very fine silk! They must be well constructed because they offer protection for the larvae and filter animal detritus from the water for the larvae to eat.

This little critter, measuring a mere two millimeters in length is invisible against its preferred habitat of lichen-covered rocks unless it moves, and you are looking very closely indeed. It is a Barklice or Booklice from the Psocodea (previously Psocoptera) order of insects. These small, primitive insects are called Booklice when they are found, as tiny brown insects, running over stored books feeding on the paste and glue of the book bindings. They also feed on stored cereal products and can therefore become a major pest. The insects are known as Barklice when they are found on the lichen-covered bark of a tree, although this species spends its time on lichen-covered rocks instead. 

Beneath the huge jaws of the insect is an extended mouthpiece consisting of a rod on each side that moves forward and backward with a forked tip. This tool is used to scrape pieces of lichen off the substrate so that it can then be shoveled into the primitive pestle-and-mortar type mouthparts to be masticated and swallowed.

If you go right to the top of Goudkoppies, on the Zebra trail, and carefully search the lichen-covered rocks around Nosey Point, and you are bound to find a few on almost every rock, grazing away like cows in a field.

I was alerted to a vulture carcass on the Spekboom river close to SPK5. On locating it, I was saddened to see that it was a young Cape Vulture, Gyps coprotheres, lying dead beside the pathway. Since this is a large, endangered raptor, I contacted the Raptor Rehabilitation Center near Dullstroom, whom we've dealt with before, and arranged to meet their representative in Lydenburg to hand over the carcass so they could try to figure out what killed it. Once she saw it, she immediately said the beak fracture (visible in the photo) was characteristic of impact with powerlines during flight. It made sense, since our powerlines run along that river.

The reason this is so sad is because the Cape Griffon is listed as endangered in South Africa, critically endangered in Namibia and regionally extinct in Swaziland and Zimbabwe, and losing one like this is so unnecessary. According to the literature available on the species, though, collisions with powerlines is responsible for the majority of unnatural deaths among Cape Vultures, although poisoning them at a carcass for the muti trade can be their biggest killer in some years.

Cape Vultures are monogamous breeders, with pairs staying together for life. All the breeding pairs in a colony, which can range from fifty pairs to as much as a thousand pairs, gather at their permanent breeding site, usually a large cliff ledge or ledges fifteen to a hundred and fifty meters above the ground, mate and then build a new nest or maintain the previous season's nest in preparation for laying. The males bring the grass and branches to the site while the female uses them to build or repair their nest. Once completed, the female will lay (almost always) one large, quarter of a kilogram egg in the nest and both sexes then spend equal amounts of time incubating it for almost two months before the egg will hatch.

After about five months, the chick will be ready to take its first flight and will still be fed and nurtured by its parents for another four months or more before becoming completely self-sufficient. It takes six years before maturity is reached and the vulture will be ready to breed itself, starting the cycle all over again.

When driving through Nooitgedacht property, on the way to the estate, if you look westwards towards the Long Tom Pass road, up Machienkloof valley, you will notice what looks like white paint on the red cliffs. That is the urea stains from a Cape Vulture colony that deserted that breeding site well over ten years ago. I'm not sure what the cause was. It is usually because of human interference. It is unfortunate because it would be quite a bonus if it was still there because, although we do see these vultures quite regularly as they regally glide through the skies above the estate, a breeding colony would provide much entertainment and many brilliant opportunities to see the best of these magnificent birds.

Oh, Joyous occasions! In August, I went for an exciting hike with my very best old Finsbury buddy, Fraser Moore, from Rock Solid, deep into the forests encircling the Steenkamps' waterfalls. We hiked straight up from the end of the path in search of a huge Yellowwood tree I was told about and thought I could see (?). It was quite hard going, so we were unable to search methodically with the equipment we had available and did not find the tree in question. Instead, we just concentrated on getting out of the gorge. It was very steep and precarious! Out onto the top of the gorge, I might add. Quite a feat, I assure you (eh, Fraser?)

Anyway, before this whole ordeal, me being the orchid-lover that I am, mentioned that there was a chance that we may encounter a special orchid, special not because it is very rare, but because of its gracious delicacy. As we approached the most precarious of circumstances, as it would be, I spotted the orchid I was searching for and exclaimed rather loudly. I'm certain Fraser though I had stumbled upon a huge serpent! It was exciting. Both of us spent an inordinate amount of time balancing on a rocky protrusion photographing the thing. A tiny jumble of air-roots (epiphitic) that would fit into your palm, nestled atop a lichen infested lateral tree branch, with two fifty-millimeter-long strands of delicate, pale green flowers, with nectar-filled spurs half that long. I might add that it was a long way down if we took a misstep!

I had only found this orchid, Mystacidium gracile, once before, right on the very tippy-top of Bushpig Alley in the north. Refer to my blog of September 2020 and you will see how excited I was to find it. But education is great, because, in that column, I said the flowers were pollinated by Hawkmoths, those moths with the long tongues that like to share your drink at sundowners. Well, I have now learned that the flowers that attract Hawkmoths are usually particularly scented and white, a bright colour that they can concentrate on while they hover above the flower and suck its nectar from within the long spur into which its long probiscis can reach. In order not to hover, the flower would have to be big enough for it to settle on This orchid flower, however, and others like it, have a different scent and are a pale green colour, not so visible to the Hawkmoth so they would struggle to hover efficiently. Instead, the tiny, too small for a large Hawkmoth to settle on, and specifically scented flowers attract settling moths, moths that rely more on smell and less on sight, that settle on the flower (instead of hovering) and insert their long probiscis' into the spur of the orchid and suck up the sweet, energy-filled nectar. Settling moths occur in a few moth families, but there are not many of them with probiscis' long enough to reach the nectar. According to Researchgate, there are five species, from three families of moth that may be attracted to this particular plant, I will need to dig deeper to find out which ones. One day... 

As you will have noticed in my previous blurbs about pollination: I am awed by the intricacies of how flowering plants and insects have co-evolved to maximise pollination efficiency. Orchids are the leaders in specialist pollination, and this is a good example indeed. 

Now for another special orchid. This one because it is non-descript and very rare. It's a Nervilia lilacea, just one little leaf, thirty millimeters wide, peeking from the forest floor. I found a whole colony of them beside the second gorge above Solitude (unit 5) in Solitude valley. I managed to photograph the leaf but will have to wait till November and or December to get a glimpse of the solitary little flower. The problem is, the tiny flower appears before the leaf, and only for a few hours! I was there more recently and couldn't even find where exactly I had seen these leaves a few months before. So, I will have to visit the spot frequently over those two months to maybe get a chance to see a flower. Not too easy to get to, but I have made a path that makes it a bit easier. Please, if you're visiting during those months and you want to see one, we can give it a try. It will only take an hour or so and, although the chances are small, it will be worth it. I'll let you know when I find a flower.

I am sometimes lucky enough to receive photos from members of wildlife spotted on the estate. This photo was taken along the Spekboom river by Dave DeVos from "The Croft's" (unit 19). It is a beautiful pic of a Half-collared Kingfisher, Alcedo semitorquata, perched beside the thickets just above the water. They are one of our iconic species on the estate and very special to view. They are usually seen perched low down in the brush alongside fast-running rivers waters or flying its fast, direct flight just above the water's surface.

It's a small kingfisher that resembles a Malachite in size and looks. The Malachite, though, has orange cheeks. Kingfishers are generally only slightly sexually dimorphic, and it is no different with this species. The one pictured above is a male because the base of its bottom bill is not tinged in red.

Another amazing sighting I had when adventuring up the Steenkamps gorge with Fraser from Rock Solid, was this bizarre fly, a Stalk-eyed Fly from the Diopsidae family. We found a whole bunch of them buzzing around the bushes, close to the ground in the early morning. According to the info I managed to find, they roost on hanging roots above the water during the night. Then, in the early morning, they gather on the bushes near the stream and the males establish a lek, a gathering of males for the purpose of competition for females. The males fac e each other with front legs splayed wide. They then push their faces up against each other, and the one with the longest stalks (largest space between the eyes) dominates and moves on to the next male. The females watch this and are attracted to the male with the widest eyes. Very sexy!

Once mating is complete, the female lays her eggs in and amongst rotting vegetation on the forest floor. The larvae hatch and consume the rotting vegetables and then enter their pupal stage. Once emerging from the pupa, the newly adult fly's stalk eyes are squished up against their bodies, so they gulp air in through their mouths and pump it up into their faces and inflate their stalks, like balloons, until they are fully extended!

This, like the extraordinarily long tail of a male peacock, is a great example of "sexual selection", where the female's preference for, in this case, wide-apart eyes, results in the males evolving physical traits which may even actually hinder survival. As long as the male can still breed. Crazy, eh?  

That's it for winter then. We have entered our springtime now and, to date, it has been rather dry, with only two decent rainfalls to speak of. But the excitement is there! Lots of new life popping up all over the place! Get on down and let's play.