We do currently have an active Crowned eagle's nest on the estate (see blog of October 2021), which is a special privilege, so I hope I'm not being too greedy....
Grasses are the most recently evolved group of plants and only began to dominate the land masses in the last five million years and less. I think the competition and the complexity of the insect-pollination system allowed a return to the wind-pollination system more feasible (the more primitive of the plants ie, conifers, and before them, the spore producing plants like ferns all used the wind), if sufficient numbers were achieved. And so, we have grasses: Flowering plants, stacked together tightly, without the need for the pretentious, and expensive, coloured petals, scents and nectar required to attract pollinators, grasses dominate by sheer numbers which are achieved through their meristems, the growing points, being at the base of the leaves, low down on the ground, so that, even if you throw fire, grazing, snow or frost at it, the plant can still grow unhindered. In fact, grasses in grasslands, prairies or steppes (different names for the same thing, really) have become so reliant on fire and grazing to minimise competition with other plants, that without them, they would regress back into shrubland and woodland.
The photo above is of the flowering inflorescence of a Stab grass, Andropogon schirensis. a common grass on the estate. The photo clearly shows the plum-coloured filaments of the stamens (male). tube-like so as to release pollen grains into the wind, and then, especially near the base (in this photo, all flowers will have a female part), the pale, feather-like stigma (female) stretched out to collect pollen from others in the wind.
A beautiful close-up of a Transvaal Dwarf chameleon, Bradypodion transvaalense (= slow-foot from the Transvaal) as it tried to sneak past me unobserved in the thickets of the forest edge near Rainbow Rivers. Alas, it failed, and I managed to capture the subdued blue and yellow tinges on its scaly skin, meaning it was not yet stressed (they turn a contrasting bright and dark colour when stressed).
The Bradypodion genus contains no less than twenty species, and they all occur in Southern Africa only, meaning they are all endemic to our country and occur naturally nowhere else. Genetic studies are underway, and it seems the species count may even increase with some near endemics occurring in tiny, specialised areas, mostly along the escarpment, of which we are part.
Chameleons are a mostly an African affair, especially Madagascar, with only a few species outside in the Mediterranean, Asia and India, all near the African side. The most widespread, including in South Africa, is the Flap-necked chameleon, the one most of you will know from the Kruger Park and elsewhere, including the western properties in our reserve like Rivendell. This species, together with a desert specialised, ground-living species, the endemic Namaqua Chameleon, both belong in the Chamaeleo genus and dig holes in which to lay their eggs, which take about three months to incubate. The South African Dwarf chameleons, of which the Transvaal Dwarf chameleon is part, all belong to the Bradypodion genus and are viviparous, which means they give birth to live young, mostly after about a year's gestation.
I have had the joy of seeing newly hatched Flap-necked chameleons before in the Kruger Park but it would be a real treat to see little new-born dwarf chameleons here on the estate. They must be the tiniest little things, considering Mommy pops out up to seventeen little lizards, one after the other, when she gives birth!
I was riding my motorbike, in the night on the Majubane road just above Tranquility (unit 15), when I sighted this Nightjar on the road. I tried to approach it, with my flashlight focused on it and managed to get this rather poor shot before it alighted and flew away. I went home, thinking it must have been a Fiery-necked nightjar, the commonly encountered nightjar on the estate, when I identified it as a European nightjar, Caprimulgus europaeus by the plumage pattern. Check it out and let me know your response. I'm sure I'm right here!
Also, aeach species of nightjar is represented by multiple subspecies whose colouration and plumage pattern differs only slightly, so, phew, after much consultation, deliberation and frustration, flipping from page to page and back again, with the limited detail on the photos, I finally settled on the greyer Asian subspecies of European nightjar, Caprimulgus europaeus ssp. umwini.
The best way, of course, to identify the similarly looking nightjars, is to listen to their calls which are very specific. This cannot be done in this case because this nightjar is a palearctic breeding migrant, meaning it breeds in the palearctic region, in this case, in Iraq and Pakistan, and migrates to the southern hemisphere, in this case Southern Africa, to escape the harsh northern winters, after which it returns home to breed. So, it has no need to make any sounds down here because its calls are reserved for mating purposes only, and when here, they are taking a break from each other.
In my blog dated September 2019, I featured a rather poor photograph of a Red Spider mite. The quality of the photo being so poor, even with the special magnifying features on my camera, because the thing wouldn't stand still and it was just over a half-a-millimeter long! And that size, for a mite, is big. This one here, above, is a giant at three millimeters long. Even at that size, on the forest floor, in among the detritus, it sure was easy to spot this bright red Red Velvet Mite, I think from the Dinothrombium genus in the Trombidiidae family, the biggest of the mites.
I was lucky with this photo, because I took it before the thing got wind of me. Once it realised I was there (I've got to get the camera very close when the subject is so small), it wouldn't stand still, again like its tiny distant cousin from the blog I mentioned earlier. Fast and zippy. Anyway, when I was gathering information on these odd creatures, I discovered that a mite, less than a millimeter long, from southern California, holds the world record for the fastest animal! That is, the speed it runs relative to the size of its body. It achieved 322 body-lengths per second. To put that into perspective, a cheetah achieves 16 body-lengths per second; the fastest insect, a species of Tiger beetle from Australia, achieves 171 body-lengths per second, the previous record-holder before someone measured the mite's speed, using high-speed photography in a laboratory and in their natural habitat.
Mites are everywhere, all around us. They fill all the common niches, from decomposers to plant-eaters to predators to parasites and even cannibals! They live in all conditions from salt water to fresh water to forests to deserts to houses and even hospitals! They can do this without us noticing because of their tiny size. They are like an advanced mix between a tick and a spider, although they fit between the Solifuges (Red Romans / Kalahari Ferrari) and the Pseudoscorpions (see blog of March 2021 to learn about these also-amazing creatures). All of them: ticks; spiders; scorpions; harvestmen; solifuges; mites; pseudoscorpions and a few others, make up the Arachnida, a class of Arthropods.
This beautiful, lanky spider is a Dark Sheetwebber, Euphrosthenopsis pulchella, and belongs in the Nursery-web and water spider family, the Pisauridae. But, as there is always an exception to the rule, they are not wandering spiders like the Nursery-web spider, who resemble and behave very similarly to the common wolf spiders (blogs September 2019 and January 2022), who do not use a web to capture prey but instead wander around actively hunting their prey, and thus, the female carries her ball-like egg sac with her while the eggs incubate (the Wolf spider carries her egg sac by her spinnerets on her abdomen while the nursery-web spider carries hers with her jaws).
The Sheetwebber, by exception, builds a horizontal, sheet-like web like a Funnel-web spider (blog of February 2020) does, also with a tunnel-like retreat to escape danger. The eggs are laid and incubate within the retreat, so she doesn't have to carry them with her like her brethren. If an insect lands on, or walks on to her sheet-like web, she darts out of her tunnel and subdues the victim with a potent venom that those same brethren require, like most wandering spiders, because they don't use silk to help subdue their prey like web bound spiders.
I found this individual in the thickets between Solitude (unit 5) and the gorge that runs past it. Exciting because I have only once seen this spider before on the estate many years ago.
It is amazing. I didn't get to see a Baboon spider for my first seven years here at Finsbury and suddenly, in the last few years, I have had a whole bunch of sightings! Every sighting, of course, is thrilling because they are so large and yet so gentle (unless you are their prey).
This is a large male Golden Baboon spider, Harpactira tigrina (see blog of Autumn 2022 and erratum thereafter). I say large because, as with most spiders, the female is much larger than the male, although in baboon spiders, the size difference is not that great, and this individual covers half my forearm! And I say male because he ran past me, away from one of my patch mosaic fires: If it was a female, she would have retreated into her silk-lined burrow, whereas males usually reside beneath a hammock of web in a nice, secluded spot, making it necessary for him to find refuge in amongst rocks during fires.
A stunning pair of Golden Waxcap mushroom, Hygrocybe chlorophana, fruiting bodies, growing from a rotting log, covered in soft mosses, on the forest floor near Steenkamps' waterfalls. It's sightings like this, coupled with the bright red Red Velvet Mite, and Knysna Turaco, that bring colour into the darkest depths of our Kloof forests. In fact, according to the literature, most Hygrocybes are brightly coloured, and indeed, I have found bright red ones in our forests too.
Golden waxcaps are associated with old, natural meadowlands in Europe called "Waxcap Grasslands", which are becoming more and more rare as we continue to alter our landscapes, making these mushrooms endangered in the northern hemisphere. In the southern hemisphere, they are associated with woodlands and forest.
The fruiting bodies are edible but not particularly tasty. Hygrocybe means "wet head", alluding to the fact that the cap is often slimy on top and, chlorophana is a bit of a misnomer because it actually means "pale green" and, as you can see, there is absolutely no pale green to be seen. Even the boffs mess up every now and again!
As you traverse the estate, especially along the rivers in the valleys, during the late summer months, you will notice bunches of pinky-maroon decorations hanging from various bushes and trees. These are bunches of fruit (winged seeds) belonging to Rambling Dock, or Turkey Rhubarb, Rumex sagittatus.
Rambling Dock is a low to medium height scrambling creeper with soft, arrow- head shaped leaves (hence the specific epithet: sagittatus) that are delicious in soups and edible like a marogo / spinach. The flowers are numerous but tiny and insignificant. It's the three-winged fruit that is attractive, and this attribute that has taken the plant overseas where it has become a major pest species, especially in Australia, Tasmania and New Zealand. Yup, most of their pest plants come from South Africa, and most of our pest plants come from Australasia! Bluddy ozzies and kiwis!
In this case, the plant is creeping up and through Bracken Fern and Yellow Sheepsdaisy. The Sheepsdaisies which are now, as I write, just after Easter weekend, beginning to bloom en masse, filling the valleys with yellow!
When photographing animals, it is best to try and get the entire body in the photo, try not to cut anything off, unless you are looking for a portrait. Now, this Brownback Grass Katydid, Tylopsis continua, if you zoom in, has the most beautiful candy-striped eyes, and, because of those super long antennae, I would have had to bring the camera much further back to fit the body in, and the eyes would have been invisible. So, I chopped the antennae by about a third just to fit the rest of the body into the frame. Those are long antennae, hence the common name for this family of orthopterans (crickets, grasshoppers), Long-horned grasshoppers. In North America, they are called Katydids, an onomatopoeia. I will use Katydid because it's a lot shorter.
In the past, I have stated that the difference between a grasshopper and a Katydid is that a grasshopper eats vegetables (grass) and is active during the day; whereas the katydid is a predator and is active during the night. That is not entirely accurate because this species, with a few others, is actually an omnivore: eating mainly grass leaves and flower petals but has also been observed eating soft-bodied aphids and caterpillars.
Also, if you look really carefully, you will notice a fine slit on the front tibia. This is a closed tympanum, a membrane that detects sound, like our ears do. Male Katydids stridulate with their forewings, producing different frequencies of clicks. Besides being species specific, the frequency of their clicks is dependent on the ambient temperature. Frequency increases with temperature increase. It is so accurate that, in North America, they can accurately calculate ambient temperature by using the formula: number of clicks per fifteen seconds, plus thirty-seven, gives the temperature in Fahrenheit (X (clicks / sec) + 37 = T (F)).
The female Brownback grass katydid hears the males call and responds by approaching him. After mating, when she is ready to lay her eggs, she cuts a slit, with her blade-like ovipositor, in the leaf sheath on a grass stalk, in which she lays her eggs. After a few weeks (or after winter if they lay at the end of summer), tiny nymphs, that look similar to the adult, emerge from the grass stalk and begin their lives of eating, hiding and mating.
Finally, at the end of the Rock Kestrel trail on Saturday during Easter weekend, not far from K9, I glimpsed this withered caterpillar resting on a mattress (?) resting on the inflorescence of on the top of a grass stalk. On closer inspection, I saw it was a dead caterpillar resting atop the cocoons of the parasitic wasps that had eaten the caterpillar out from the inside, then spun cocoons and some have clearly already pupated as their cocoons are empty.
The culprit is an Ichneumonid wasp (See blog of February 2020). The wasp uses its long, slender ovipositor (instead of a sting) to inject an egg into the victim, a caterpillar. Amazingly, in some species and more than likely this one too, the single egg "reads" the victims species, size, age and how long until it goes into its pupa, and then divides the egg the requisite number of times so that there is enough food for the number of eggs that are formed! That is simply incredible! Then these larvae do not kill the caterpillar, so that it can eat, albeit in poor condition because it is being slowly devoured from the inside, to continue nourishing the maggots within. By the time the maggots are ready to pupate, the caterpillar has died and they drill through its integument and spin their cocoon beneath it. More commonly, in some species, the cocoons stick out of the integument like quills on a porcupine.
There's more! There are some caterpillar species, who too regularly had fallen victim to these wasps in the distant past, that have evolved a pattern on their bodies that looks so very much like these cocoons sticking out, that the ichneumonid wasp avoids it, apparently convinced that the caterpillar has already been parasitised! Crumbs! It's crazy out there :)
That's it for summer here at the estate. Already feeling the chill in the morning air. But we all know that the estate is as entertaining in the winter as it is in the summer. Remember, if I am available during your visit, I am more than happy to take you and your guests on doodles, walks or hikes. Just contact me at jimmy@finsbury.co.za. Or on the radio when you arrive here. See you then!
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