March 2020

MARCH 2020

Wow, it is amazing how quickly things can change. The world has pretty much cancelled Easter because, like, 2 billion people are on lockdown due to a global viral pandemic. Who woulda thunk? March is not finished yet but I thought I would post my monthly blog a little earlier since you are all holed up at home.

The rainfall during March has reached 99mm which has brought the total seasonal figure to over 600mm, about a third of our mean average seasonal figure. And once again, even though the rainfall is quite low, we have had good absorbing rain with minimal run-off, resulting in good vegetable growth and lots of life. Check out some of the stuff I got to see this month while carrying out my duties here in the mountains:

This huge, terrifying wasp belongs to the Hemipepsis genus in the Spider-hunting wasp family Pompilidae. The common name is a Tarantula Hawk and it is amongst the largest of wasps, longer that 50mm. Very difficult to photograph because it vibrates and hums, almost like it is emitting electrical currents as it moves ominously through the thickets in search of the hide-away of a Baboon Spider (see November 2019 blog - Harpactrinae). It really is quite scary. And it should be, since it is one of only three species of Hymenopterans (Bees, wasps and ants) to be rated 4 on the Schmidt's Sting Pain Index. This is a scale devised by the entomologist, Justin Schmidt that takes the following into consideration: venom composition; size of the stinger, length of effectiveness; and his own experience of the pain, which is subjective but consistent because he tries them all. 1 on the scale is the mildest sting, like those from Miner bees, while 2 is where the majority of wasps and the Honey bee is placed. 4 is where he has placed the most painful of stings, the Bullet Ant, Paraponera clavata, the Warrior Wasp, Synoeca septentrionalis, and the Tarantula Hawks from the Hemipepsis genus. He describes the sting from 4 on the scale as such:" Pure, intense, brilliant pain...like walking over flaming charcoal with a 3 inch nail embedded in your heel!". That's how he described the Bullet ant. He says the only positive thing about a Tarantula Hawk's sting is that it is short-lived, only about 5 minutes. The stinger is only present on female Hymenopterans and they use them to prepare food for their offspring. I once saw what she does, when she finds the hole of a Baboon spider, in the Timbavati Reserve in the Lowveld:

She tickled the web lining the burrow until the Baboon spider emerged to investigate. When the spider saw the wasp, it reared it's front legs up and exposed its fangs. The wasp and the spider sparred for a minute or so, moving back and forth across the ground until the wasp managed to grapple with the spider and sting it in the face. The spider immediately froze. The wasp flipped it onto its back and dragged it back to its burrow and disappeared inside with it. After some time, the wasp emerged and picked up a dead leaf from the floor and covered the entrance to the spider's burrow with it. She then faced her back to the burrow and kicked sand over the leaf. She picked up some small stones and littered them around until the spider's burrow entrance was invisible before she left the scene. Later, after reading about it, I found out that the spider was paralysed but still alive and that she placed it in its own chamber and laid an egg on it while she was down there. Later the wasp larva would have hatched into a grub and fed off the living spider, only eating the tissue and not the organs so the spider remained fresh and alive until the end. The larva then pupated and emerged as an adult wasp in the safety of the spider's burrow. When she is not terrorising spiders and all other things, the female and male wasps feed on nectar and, as explained in my blog of January 2019, are very important pollinators of certain Milkweed plants. 

This Rain spider, Palystes supercilliosus, 10cm from front to back, would certainly fall to the Tarantula Hawk if she were there. But it is rare to find this spider on the floor where the wasp would be searching since it spends its time up in trees (or on the wall in your home!). The only reason the spider was on the forest floor was because it fell from a tree that I disturbed, onto my shoulder and then onto the floor. I did let out a little yelp, yes. There is, though, a species of Pompillid wasp that specialises in using Rain spiders as a food source for their offspring, like the Tarantula Hawk does to Baboon spiders. Anyway, this is probably a gravid female spider because she has well-defined markings where males and females that are not ready to lay eggs are more plain coloured. She will soon construct a large nest of leaves held together by silk in the foliage of a tree in which she will lay her eggs. She will construct 3 of these nests in her 2 year lifespan. The spiderlings remain in this nursery, guarded by their mother, until they are big enough to bite their way out of it. The mother is very aggressive at this time and bites readily. Fortunately the spider's venom is not very potent and will only cause a small, necrotic wound at the bite site. The Rain Spider is a hunting spider, not using its silk to catch it's prey, but rather actively hunting for prey, mostly at night. Prey consists mainly of insects and other arthropods but quite often, in the home, also Lygodactylus Gekkos (also featured in my blog of January 2019, coincidently), giving them the alternate common name of Lizard Spiders.

If you search through the undergrowth during the month of March, you may find yourself the weirdest looking mushroom you could imagine, a Star Stinkhorn fruiting body. This bright red mushroom with a diameter of about 50mm grows out of decaying debris on the floor and once it has fully developed, it produces gleba, dark brown powdery spores that deliquesce into a stinking brown mucus that is very attractive to Bot flies and their kin. The flies then help to spread the reproductive spores of the fungus around in the environment. The scientific name, Aseroe rubra, means "disgusting juice, red" and it is very descriptive.  

I'm sure we have all had the privilege of seeing the family of Klipspringers, Oreotragus oreotragus, on the hill in Rivendel when you access the estate. That hill is actually called Klipspringer Hill because of the pair and their offspring. Male and female Klipspringers are monogamous and maintain a life-long bond that is only broken when one of them dies. They establish a well-defined territory that is demarcated by middens of droppings and pastings from their pre-orbital glands (equivalent to our lacrimal gland that produces tears), a territory which the male defends against other males and the female defends against other females. Even when inside their territory, the male and female always remain close to each other. So when they detect danger, their alarm call is sang in a duet, a buzzing call made first by the male and then followed up by the female. They bare a single lamb (rarely twins) who is raised in the safety of the territory and evicted after a year. Special adaptions for their rocky habitat include thick, hollow hairs that help insulate against the temperature extremes in rocky terrain and also cushion their fall when they lose their footing, making the hair the preferred stuffing for saddles in the old days. There hooves are also inverted and rather rubbery, helping them to stick to the rocks and giving them a unique spoor that is easy to identify. The picture above is of the old man with his son who is almost at the age where he will be told to get out and get a job...

I couldn't resist taking a photo of this Large Sprite or Christmas Forester, Celaenorrhinus mokeezi, resting on a leaf  in a lone shaft of sunlight in the Steenkamps gorge forest near the waterfalls. They are quite hard to spot because they inhabit the dark, shaded forests but when they rest up in the sun like this, the gold on their wings shines beautifully. The larvae feed on Buckweed plants (Isoglossa woodii) which are non-descript understory plants also favoured as browse by bushbuck and Duiker, hence the name Buckweed. I have not found any of these plants here on the estate and as far as I know they are confined to coastal forests but it is the only plant listed as the host for this butterfly. We do have a few species of Acanthaceae that grow as understory plants in our forests like Hypoestesa aristate and H. triflora. I will dig a little deeper but if anyone can shed some light, please do. 

The 25 plant species in the Amaryllis family all have bold, showy flowers and although they are all endemic to Southern Africa, they are found throughout the world as garden subjects because of their spectacular flowers. This, the Narrow-leaved Spider Lily, Nerine angustifolia, is no exception and was in full bloom for the month of March throughout the estate alongside high altitude streams in the grasslands and in marshy areas. I remember finding a large colony of about 20 individuals along the stream just below the sundowner spot in Hidden Valley a few years ago. It was such a spectacular sight that I took people to show them the following day and they were all gone. After some investigation I saw that a herd of Eland were browsing the area and had eaten each and every flower. Must taste good? Anyway, they make a great garden subject and if you plant a bunch of them in a sunny spot with rich soil, you will be rewarded by a dazzling show each late summer.

This is Rhombic Night Adder, Causus rhombeatus, the fastest of the Vipers, it can travel at 3,3km/h which is quite fast for a snake. The snake that holds the record for the fastest speed over the ground is the Black Mamba, who can travel at 19km/h! The Night Adder is also easy to tame as they do not bite readily and will relax completely after being captive for only a short period of time. But although a bite from one of these should just result in local pain, swelling and mild necrosis which usually disappears within a few days, there has been a case where a minor was bitten and doctors had to perform a fasciotomy, where the integument and fascia has to be sliced to alleviate swelling pressure (this procedure is usually performed for Puff Adder bites). The snake can tolerate the bufotoxins produced by the paratoid glands of toads and so specialises in them as prey, although they will also take small mammals, like rats, resulting in many sightings of them in the recycling area near the office, attractive to rodents, where this photo was taken. 

This odd-looking, pock-marked ant is a Rugged Ringbum ant (what a lekker name!), Bothroponera pumicosa, and belongs to the Ponerinae subfamily of ants, which is also the most primitive grouping of ants. Most ponerines, including the Rugged Ringbum, live in very small colonies of up to a dozen individuals, though some, like the notorious Matabele ant, Megaponera analis, live in colonies numbering more than a thousand individuals. They do not have a queen but instead a dominant worker that is fertile. Remember, in all ants the workers are female but, in this case, the one that is stress-free will have certain physiological processes triggered that enable her to conceive. So, to remain the only one that is stress-free, she bullies her fellow workers constantly, never allowing their stress levels to drop to the point that they would become fertile too. A cold and crazy system, but it works. In fact Wild Dogs do a similar thing. One thing all ponerines have in common is a painful sting, from the Streblognathis ant that stung me so painfully (see blog "The jolly season 2018) to the Matabele ants in the Lowveld (a mighty sting but still not as bad as the Streblognathis) to this lady who I have not yet been stung by. But at 12mm in length, she wouldn't seem like she had a powerful sting, eh? Google the Bullet Ant.

This is one of the 7 species of mosquito in the Anopheles gambiae complex. These 7 species were all previously thought to be the same species. From East to South Africa. The species responsible for the transmission of the protozoan Plasmodium falciparum that causes the most deadly of the 4 kinds of Malaria. I was not worried when this mozzie bit me because, although the mosquito occurs here in our temperate climate, the protozoan does not. And the mosquito has to first be infected by the protozoan before it can then infect a human by passing it on. This is why, once one person gets Malaria in an area, then it quickly spreads to others. Not because he is contagious but because each mosquito that bites the infected person then also picks up the Plasmodium and passes it on to the next person she bites. Only once she has had a full, satisfying meal and her abdomen is bloated and ready to pop, will she rest up in a hiding place to allow her eggs to develop. Interestingly, it has been found that mozzies infected with the Plasmodium protozoan develop a keener sense of smell. They use their palps to detect carbon dioxide and are particularly attracted to human foot adours! The Plasmodium also influences their behavior, making them more desperate and less adverse to risk taking. Weird.

 So the male, with feathery antennae like nocturnal moths, does not bite humans at all. And although the word Anopheles is ancient Greek for "unprofitable or useless", the male and the female before she is mated with, are actually important night-time pollinators because they eat nectar from night-time flowers. It is also rather easy to differentiate between the Anopheles genus and the other common genus of mosquito, Aedes, by observing a few behavioral traits: Firstly, when resting on a substrate or on your ankle, the Anopheles' abdomen points from a 45 degree angle to a right angle from the substrate whereas an Aedes mozzie's abdomen lies parallel. This includes when they are sucking your blood like in the photo. Secondly, the aquatic larvae of the Anopheles does not have a breathing tube so it has to lie parallel with the water surface whereas the larvae of an Aedes mosquito does have a breathing tube, so can allow its body to hang below the waters surface from a 45 degree angle to a right angle (opposite rule to the resting one). Also visually, the adult Anopheles has black and white scales on its wings which is lacking in the other genus. 

So once the female has allowed her eggs to develop, she lays 50 or so of them, attached to little floating devices, onto the surface of still water. Once hatched, the larvae feed on bacteria and algae in the water and after 4 instars, they pupate, still in the water. The time it takes from the egg being laid on the water to the adult emerging from the pupa is temperature dependent with warmer weather speeding up the process to a minimum of 7 days. So although this is the most common genus on the estate, in my opinion, we don't have to worry because it is too cool for the protozoan, Although global warming has already spread the distribution of Plasmodium in some areas.

In my blog of October 2019 I mentioned how rarely I have seen the Rhinkals, Hemachatus haemachatus, and how excited I was to find the inverted sloughed skin of one up on Goudkoppies. Well, since January I have had 2 encounters! Unfortunately, they are so timid that I would have had to hurt them, on both occasions, to get them to stand up for a nice photo, so I just got shots of them sailing toward the nearest hole with their hoods expanded. The first sighting in January sailed out from beneath the logs that I was chain-sawing at the rehabilitation plot where the Pine plantation has been removed between Cochy-bundhu (unit1) and Rainbow Creek (unit2). I managed to get right up to it before it disappeared down a hole in the ground. The second sighting was a week ago while pushing my bike up the zig-zag road leading up to the Troutkloof ruins on the Zebra trail. This one (bottom of the picture) was much more active - because I nearly trod on it - so I did not have much time to take a photo. But, as you can see, it had a bright yellow hood! Although it was a good meter long, it must have been a youngster because its body colouration is also brighter. So I finally got some photos (besides that of the skin) of a Rhinkals for my data base..  

Looks like it is standing on water, doesn't it? It's actually standing on its very delicate sheet web and its a Nursery Web spider. In my last blog, I featured a Funnel Web spider that constructs a horizontal sheet web to capture prey. The Nursery Web spider, Dendrolycosa sp. from the Pisauridae, also constructs a horizontal sheet web. But not to capture prey. They are hunting spiders, like the Rain spider from before. Instead, she constructs the web around her cluster of eggs and guards them (above) so that the spiderlings are protected from the elements. Regarding the introduction to this spider's blurb, incidentally, the Water spider, the one that runs on water and even eats small fish, is also from this family. They look rather similar, too.

There are 2 species of Suids (pigs) on the estate and they occupy very different niches, in an ecological sense, to avoid competing with each other. The Bushpig, Potomachoerus larvatus, is largely nocturnal and inhabit thick, bushy terrain and forest while the Warthog, Phacochoerus aethiopicus, is a diurnal animal that prefers more open areas. Because of this, Warthogs are seen much more regularly on the estate but there are still plenty of Bushpig. But recently I, for the very first time, got to see both species together, interacting in the open grassy slopes above K13 (same place you saw the leopard with two cubs, Charles Van Heerden!). In the centre of the picture is a large male Warthog, facing away from us, recently disturbed from his mud wallow by the Bushpigs flanking him on both sides. There was at least one  little Bushpig with its mother on the right behind the bush. Both species seemed to respect each other although I got the feeling that the Warthog was the more confident one as they all went their own way. Exciting stuff.

I was very lucky to get these two shots, that I have fused together, of a Clearwing moth, from the Sesiidae, because they are not very abundant. I stumbled upon this beaut in the high altitude grasslands east of Bulldozer Creek. These day active moths have evolved aposematic colouration (see the blurb on Nassinia pretorie in last month's blog) allowing them to mimic aggressive bees and wasps. I have photos of another 3 species of moth to add to my list for the month and they appear below: 

A female cosmopolitan Beet Webworm moth, Spoladea recurvalis,nocturnal.

A male Bar Maiden, nocturnal.

A day active, aposematic Crimson Speckled Footman, Utethisa pulchella, sex unknown. Beautiful!

Anyway, that's it for now. I will be doing a bunch of patrols during this lockdown time because anti poaching is still regarded as an essential service and I will, hopefully, not be encountering any other people. During these escapades I will gather as much material as I can to keep you entertained there in your homes. I know a little about viruses and, I tell you, we are doing the right thing by being disciplined and staying home, practicing social distancing (something I thought psychiatrists said was a negative thing!) and just being aware. Aware that this virus is here and will only be defeated if we all play our part. Good luck and remember to exercise!